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Diffstat (limited to 'src/hardware/reelmagic/tools/original_pl_mpeg.h')
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diff --git a/src/hardware/reelmagic/tools/original_pl_mpeg.h b/src/hardware/reelmagic/tools/original_pl_mpeg.h new file mode 100644 index 000000000..b69c3b935 --- /dev/null +++ b/src/hardware/reelmagic/tools/original_pl_mpeg.h @@ -0,0 +1,4267 @@ +/* +PL_MPEG - MPEG1 Video decoder, MP2 Audio decoder, MPEG-PS demuxer + +Dominic Szablewski - https://phoboslab.org + + +-- LICENSE: The MIT License(MIT) + +Copyright(c) 2019 Dominic Szablewski + +Permission is hereby granted, free of charge, to any person obtaining a copy of +this software and associated documentation files(the "Software"), to deal in +the Software without restriction, including without limitation the rights to +use, copy, modify, merge, publish, distribute, sublicense, and / or sell copies +of the Software, and to permit persons to whom the Software is furnished to do +so, subject to the following conditions : +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. + + + + +-- Synopsis + +// Define `PL_MPEG_IMPLEMENTATION` in *one* C/C++ file before including this +// library to create the implementation. + +#define PL_MPEG_IMPLEMENTATION +#include "plmpeg.h" + +// This function gets called for each decoded video frame +void my_video_callback(plm_t *plm, plm_frame_t *frame, void *user) { + // Do something with frame->y.data, frame->cr.data, frame->cb.data +} + +// This function gets called for each decoded audio frame +void my_audio_callback(plm_t *plm, plm_samples_t *frame, void *user) { + // Do something with samples->interleaved +} + +// Load a .mpg (MPEG Program Stream) file +plm_t *plm = plm_create_with_filename("some-file.mpg"); + +// Install the video & audio decode callbacks +plm_set_video_decode_callback(plm, my_video_callback, my_data); +plm_set_audio_decode_callback(plm, my_audio_callback, my_data); + + +// Decode +do { + plm_decode(plm, time_since_last_call); +} while (!plm_has_ended(plm)); + +// All done +plm_destroy(plm); + + + +-- Documentation + +This library provides several interfaces to load, demux and decode MPEG video +and audio data. A high-level API combines the demuxer, video & audio decoders +in an easy to use wrapper. + +Lower-level APIs for accessing the demuxer, video decoder and audio decoder, +as well as providing different data sources are also available. + +Interfaces are written in an object orientet style, meaning you create object +instances via various different constructor functions (plm_*create()), +do some work on them and later dispose them via plm_*destroy(). + +plm_* ......... the high-level interface, combining demuxer and decoders +plm_buffer_* .. the data source used by all interfaces +plm_demux_* ... the MPEG-PS demuxer +plm_video_* ... the MPEG1 Video ("mpeg1") decoder +plm_audio_* ... the MPEG1 Audio Layer II ("mp2") decoder + + +With the high-level interface you have two options to decode video & audio: + + 1. Use plm_decode() and just hand over the delta time since the last call. + It will decode everything needed and call your callbacks (specified through + plm_set_{video|audio}_decode_callback()) any number of times. + + 2. Use plm_decode_video() and plm_decode_audio() to decode exactly one + frame of video or audio data at a time. How you handle the synchronization + of both streams is up to you. + +If you only want to decode video *or* audio through these functions, you should +disable the other stream (plm_set_{video|audio}_enabled(FALSE)) + +Video data is decoded into a struct with all 3 planes (Y, Cr, Cb) stored in +separate buffers. You can either convert this to RGB on the CPU (slow) via the +plm_frame_to_rgb() function or do it on the GPU with the following matrix: + +mat4 bt601 = mat4( + 1.16438, 0.00000, 1.59603, -0.87079, + 1.16438, -0.39176, -0.81297, 0.52959, + 1.16438, 2.01723, 0.00000, -1.08139, + 0, 0, 0, 1 +); +gl_FragColor = vec4(y, cb, cr, 1.0) * bt601; + +Audio data is decoded into a struct with either one single float array with the +samples for the left and right channel interleaved, or if the +PLM_AUDIO_SEPARATE_CHANNELS is defined *before* including this library, into +two separate float arrays - one for each channel. + + +Data can be supplied to the high level interface, the demuxer and the decoders +in three different ways: + + 1. Using plm_create_from_filename() or with a file handle with + plm_create_from_file(). + + 2. Using plm_create_with_memory() and supplying a pointer to memory that + contains the whole file. + + 3. Using plm_create_with_buffer(), supplying your own plm_buffer_t instance and + periodically writing to this buffer. + +When using your own plm_buffer_t instance, you can fill this buffer using +plm_buffer_write(). You can either monitor plm_buffer_get_remaining() and push +data when appropriate, or install a callback on the buffer with +plm_buffer_set_load_callback() that gets called whenever the buffer needs more +data. + +A buffer created with plm_buffer_create_with_capacity() is treated as a ring +buffer, meaning that data that has already been read, will be discarded. In +contrast, a buffer created with plm_buffer_create_for_appending() will keep all +data written to it in memory. This enables seeking in the already loaded data. + + +There should be no need to use the lower level plm_demux_*, plm_video_* and +plm_audio_* functions, if all you want to do is read/decode an MPEG-PS file. +However, if you get raw mpeg1video data or raw mp2 audio data from a different +source, these functions can be used to decode the raw data directly. Similarly, +if you only want to analyze an MPEG-PS file or extract raw video or audio +packets from it, you can use the plm_demux_* functions. + + +This library uses malloc(), realloc() and free() to manage memory. Typically +all allocation happens up-front when creating the interface. However, the +default buffer size may be too small for certain inputs. In these cases plmpeg +will realloc() the buffer with a larger size whenever needed. You can configure +the default buffer size by defining PLM_BUFFER_DEFAULT_SIZE *before* +including this library. + + +See below for detailed the API documentation. + +*/ + + +#ifndef PL_MPEG_H +#define PL_MPEG_H + +#include <stdint.h> +#include <stdio.h> + + +#ifdef __cplusplus +extern "C" { +#endif + +// ----------------------------------------------------------------------------- +// Public Data Types + + +// Object types for the various interfaces + +typedef struct plm_t plm_t; +typedef struct plm_buffer_t plm_buffer_t; +typedef struct plm_demux_t plm_demux_t; +typedef struct plm_video_t plm_video_t; +typedef struct plm_audio_t plm_audio_t; + + +// Demuxed MPEG PS packet +// The type maps directly to the various MPEG-PES start codes. PTS is the +// presentation time stamp of the packet in seconds. Note that not all packets +// have a PTS value, indicated by PLM_PACKET_INVALID_TS. + +#define PLM_PACKET_INVALID_TS -1 + +typedef struct { + int type; + double pts; + size_t length; + uint8_t *data; +} plm_packet_t; + + +// Decoded Video Plane +// The byte length of the data is width * height. Note that different planes +// have different sizes: the Luma plane (Y) is double the size of each of +// the two Chroma planes (Cr, Cb) - i.e. 4 times the byte length. +// Also note that the size of the plane does *not* denote the size of the +// displayed frame. The sizes of planes are always rounded up to the nearest +// macroblock (16px). + +typedef struct { + unsigned int width; + unsigned int height; + uint8_t *data; +} plm_plane_t; + + +// Decoded Video Frame +// width and height denote the desired display size of the frame. This may be +// different from the internal size of the 3 planes. + +typedef struct { + double time; + unsigned int width; + unsigned int height; + plm_plane_t y; + plm_plane_t cr; + plm_plane_t cb; +} plm_frame_t; + + +// Callback function type for decoded video frames used by the high-level +// plm_* interface + +typedef void(*plm_video_decode_callback) + (plm_t *self, plm_frame_t *frame, void *user); + + +// Decoded Audio Samples +// Samples are stored as normalized (-1, 1) float either interleaved, or if +// PLM_AUDIO_SEPARATE_CHANNELS is defined, in two separate arrays. +// The `count` is always PLM_AUDIO_SAMPLES_PER_FRAME and just there for +// convenience. + +#define PLM_AUDIO_SAMPLES_PER_FRAME 1152 + +typedef struct { + double time; + unsigned int count; + #ifdef PLM_AUDIO_SEPARATE_CHANNELS + float left[PLM_AUDIO_SAMPLES_PER_FRAME]; + float right[PLM_AUDIO_SAMPLES_PER_FRAME]; + #else + float interleaved[PLM_AUDIO_SAMPLES_PER_FRAME * 2]; + #endif +} plm_samples_t; + + +// Callback function type for decoded audio samples used by the high-level +// plm_* interface + +typedef void(*plm_audio_decode_callback) + (plm_t *self, plm_samples_t *samples, void *user); + + +// Callback function for plm_buffer when it needs more data + +typedef void(*plm_buffer_load_callback)(plm_buffer_t *self, void *user); + + + +// ----------------------------------------------------------------------------- +// plm_* public API +// High-Level API for loading/demuxing/decoding MPEG-PS data + + +// Create a plmpeg instance with a filename. Returns NULL if the file could not +// be opened. + +plm_t *plm_create_with_filename(const char *filename); + + +// Create a plmpeg instance with a file handle. Pass TRUE to close_when_done to +// let plmpeg call fclose() on the handle when plm_destroy() is called. + +plm_t *plm_create_with_file(FILE *fh, int close_when_done); + + +// Create a plmpeg instance with a pointer to memory as source. This assumes the +// whole file is in memory. The memory is not copied. Pass TRUE to +// free_when_done to let plmpeg call free() on the pointer when plm_destroy() +// is called. + +plm_t *plm_create_with_memory(uint8_t *bytes, size_t length, int free_when_done); + + +// Create a plmpeg instance with a plm_buffer as source. Pass TRUE to +// destroy_when_done to let plmpeg call plm_buffer_destroy() on the buffer when +// plm_destroy() is called. + +plm_t *plm_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done); + + +// Destroy a plmpeg instance and free all data. + +void plm_destroy(plm_t *self); + + +// Get whether we have headers on all available streams and we can accurately +// report the number of video/audio streams, video dimensions, framerate and +// audio samplerate. +// This returns FALSE if the file is not an MPEG-PS file or - when not using a +// file as source - when not enough data is available yet. + +int plm_has_headers(plm_t *self); + + +// Get or set whether video decoding is enabled. Default TRUE. + +int plm_get_video_enabled(plm_t *self); +void plm_set_video_enabled(plm_t *self, int enabled); + + +// Get the number of video streams (0--1) reported in the system header. + +int plm_get_num_video_streams(plm_t *self); + + +// Get the display width/height of the video stream. + +int plm_get_width(plm_t *self); +int plm_get_height(plm_t *self); + + +// Get the framerate of the video stream in frames per second. + +double plm_get_framerate(plm_t *self); + + +// Get or set whether audio decoding is enabled. Default TRUE. + +int plm_get_audio_enabled(plm_t *self); +void plm_set_audio_enabled(plm_t *self, int enabled); + + +// Get the number of audio streams (0--4) reported in the system header. + +int plm_get_num_audio_streams(plm_t *self); + + +// Set the desired audio stream (0--3). Default 0. + +void plm_set_audio_stream(plm_t *self, int stream_index); + + +// Get the samplerate of the audio stream in samples per second. + +int plm_get_samplerate(plm_t *self); + + +// Get or set the audio lead time in seconds - the time in which audio samples +// are decoded in advance (or behind) the video decode time. Typically this +// should be set to the duration of the buffer of the audio API that you use +// for output. E.g. for SDL2: (SDL_AudioSpec.samples / samplerate) + +double plm_get_audio_lead_time(plm_t *self); +void plm_set_audio_lead_time(plm_t *self, double lead_time); + + +// Get the current internal time in seconds. + +double plm_get_time(plm_t *self); + + +// Get the video duration of the underlying source in seconds. + +double plm_get_duration(plm_t *self); + + +// Rewind all buffers back to the beginning. + +void plm_rewind(plm_t *self); + + +// Get or set looping. Default FALSE. + +int plm_get_loop(plm_t *self); +void plm_set_loop(plm_t *self, int loop); + + +// Get whether the file has ended. If looping is enabled, this will always +// return FALSE. + +int plm_has_ended(plm_t *self); + + +// Set the callback for decoded video frames used with plm_decode(). If no +// callback is set, video data will be ignored and not be decoded. The *user +// Parameter will be passed to your callback. + +void plm_set_video_decode_callback(plm_t *self, plm_video_decode_callback fp, void *user); + + +// Set the callback for decoded audio samples used with plm_decode(). If no +// callback is set, audio data will be ignored and not be decoded. The *user +// Parameter will be passed to your callback. + +void plm_set_audio_decode_callback(plm_t *self, plm_audio_decode_callback fp, void *user); + + +// Advance the internal timer by seconds and decode video/audio up to this time. +// This will call the video_decode_callback and audio_decode_callback any number +// of times. A frame-skip is not implemented, i.e. everything up to current time +// will be decoded. + +void plm_decode(plm_t *self, double seconds); + + +// Decode and return one video frame. Returns NULL if no frame could be decoded +// (either because the source ended or data is corrupt). If you only want to +// decode video, you should disable audio via plm_set_audio_enabled(). +// The returned plm_frame_t is valid until the next call to plm_decode_video() +// or until plm_destroy() is called. + +plm_frame_t *plm_decode_video(plm_t *self); + + +// Decode and return one audio frame. Returns NULL if no frame could be decoded +// (either because the source ended or data is corrupt). If you only want to +// decode audio, you should disable video via plm_set_video_enabled(). +// The returned plm_samples_t is valid until the next call to plm_decode_audio() +// or until plm_destroy() is called. + +plm_samples_t *plm_decode_audio(plm_t *self); + + +// Seek to the specified time, clamped between 0 -- duration. This can only be +// used when the underlying plm_buffer is seekable, i.e. for files, fixed +// memory buffers or _for_appending buffers. +// If seek_exact is TRUE this will seek to the exact time, otherwise it will +// seek to the last intra frame just before the desired time. Exact seeking can +// be slow, because all frames up to the seeked one have to be decoded on top of +// the previous intra frame. +// If seeking succeeds, this function will call the video_decode_callback +// exactly once with the target frame. If audio is enabled, it will also call +// the audio_decode_callback any number of times, until the audio_lead_time is +// satisfied. +// Returns TRUE if seeking succeeded or FALSE if no frame could be found. + +int plm_seek(plm_t *self, double time, int seek_exact); + + +// Similar to plm_seek(), but will not call the video_decode_callback, +// audio_decode_callback or make any attempts to sync audio. +// Returns the found frame or NULL if no frame could be found. + +plm_frame_t *plm_seek_frame(plm_t *self, double time, int seek_exact); + + + +// ----------------------------------------------------------------------------- +// plm_buffer public API +// Provides the data source for all other plm_* interfaces + + +// The default size for buffers created from files or by the high-level API + +#ifndef PLM_BUFFER_DEFAULT_SIZE +#define PLM_BUFFER_DEFAULT_SIZE (128 * 1024) +#endif + + +// Create a buffer instance with a filename. Returns NULL if the file could not +// be opened. + +plm_buffer_t *plm_buffer_create_with_filename(const char *filename); + + +// Create a buffer instance with a file handle. Pass TRUE to close_when_done +// to let plmpeg call fclose() on the handle when plm_destroy() is called. + +plm_buffer_t *plm_buffer_create_with_file(FILE *fh, int close_when_done); + + +// Create a buffer instance with a pointer to memory as source. This assumes +// the whole file is in memory. The bytes are not copied. Pass 1 to +// free_when_done to let plmpeg call free() on the pointer when plm_destroy() +// is called. + +plm_buffer_t *plm_buffer_create_with_memory(uint8_t *bytes, size_t length, int free_when_done); + + +// Create an empty buffer with an initial capacity. The buffer will grow +// as needed. Data that has already been read, will be discarded. + +plm_buffer_t *plm_buffer_create_with_capacity(size_t capacity); + + +// Create an empty buffer with an initial capacity. The buffer will grow +// as needed. Decoded data will *not* be discarded. This can be used when +// loading a file over the network, without needing to throttle the download. +// It also allows for seeking in the already loaded data. + +plm_buffer_t *plm_buffer_create_for_appending(size_t initial_capacity); + + +// Destroy a buffer instance and free all data + +void plm_buffer_destroy(plm_buffer_t *self); + + +// Copy data into the buffer. If the data to be written is larger than the +// available space, the buffer will realloc() with a larger capacity. +// Returns the number of bytes written. This will always be the same as the +// passed in length, except when the buffer was created _with_memory() for +// which _write() is forbidden. + +size_t plm_buffer_write(plm_buffer_t *self, uint8_t *bytes, size_t length); + + +// Mark the current byte length as the end of this buffer and signal that no +// more data is expected to be written to it. This function should be called +// just after the last plm_buffer_write(). +// For _with_capacity buffers, this is cleared on a plm_buffer_rewind(). + +void plm_buffer_signal_end(plm_buffer_t *self); + + +// Set a callback that is called whenever the buffer needs more data + +void plm_buffer_set_load_callback(plm_buffer_t *self, plm_buffer_load_callback fp, void *user); + + +// Rewind the buffer back to the beginning. When loading from a file handle, +// this also seeks to the beginning of the file. + +void plm_buffer_rewind(plm_buffer_t *self); + + +// Get the total size. For files, this returns the file size. For all other +// types it returns the number of bytes currently in the buffer. + +size_t plm_buffer_get_size(plm_buffer_t *self); + + +// Get the number of remaining (yet unread) bytes in the buffer. This can be +// useful to throttle writing. + +size_t plm_buffer_get_remaining(plm_buffer_t *self); + + +// Get whether the read position of the buffer is at the end and no more data +// is expected. + +int plm_buffer_has_ended(plm_buffer_t *self); + + + +// ----------------------------------------------------------------------------- +// plm_demux public API +// Demux an MPEG Program Stream (PS) data into separate packages + + +// Various Packet Types + +static const int PLM_DEMUX_PACKET_PRIVATE = 0xBD; +static const int PLM_DEMUX_PACKET_AUDIO_1 = 0xC0; +static const int PLM_DEMUX_PACKET_AUDIO_2 = 0xC1; +static const int PLM_DEMUX_PACKET_AUDIO_3 = 0xC2; +static const int PLM_DEMUX_PACKET_AUDIO_4 = 0xC2; +static const int PLM_DEMUX_PACKET_VIDEO_1 = 0xE0; + + +// Create a demuxer with a plm_buffer as source. This will also attempt to read +// the pack and system headers from the buffer. + +plm_demux_t *plm_demux_create(plm_buffer_t *buffer, int destroy_when_done); + + +// Destroy a demuxer and free all data. + +void plm_demux_destroy(plm_demux_t *self); + + +// Returns TRUE/FALSE whether pack and system headers have been found. This will +// attempt to read the headers if non are present yet. + +int plm_demux_has_headers(plm_demux_t *self); + + +// Returns the number of video streams found in the system header. This will +// attempt to read the system header if non is present yet. + +int plm_demux_get_num_video_streams(plm_demux_t *self); + + +// Returns the number of audio streams found in the system header. This will +// attempt to read the system header if non is present yet. + +int plm_demux_get_num_audio_streams(plm_demux_t *self); + + +// Rewind the internal buffer. See plm_buffer_rewind(). + +void plm_demux_rewind(plm_demux_t *self); + + +// Get whether the file has ended. This will be cleared on seeking or rewind. + +int plm_demux_has_ended(plm_demux_t *self); + + +// Seek to a packet of the specified type with a PTS just before specified time. +// If force_intra is TRUE, only packets containing an intra frame will be +// considered - this only makes sense when the type is PLM_DEMUX_PACKET_VIDEO_1. +// Note that the specified time is considered 0-based, regardless of the first +// PTS in the data source. + +plm_packet_t *plm_demux_seek(plm_demux_t *self, double time, int type, int force_intra); + + +// Get the PTS of the first packet of this type. Returns PLM_PACKET_INVALID_TS +// if not packet of this packet type can be found. + +double plm_demux_get_start_time(plm_demux_t *self, int type); + + +// Get the duration for the specified packet type - i.e. the span between the +// the first PTS and the last PTS in the data source. This only makes sense when +// the underlying data source is a file or fixed memory. + +double plm_demux_get_duration(plm_demux_t *self, int type); + + +// Decode and return the next packet. The returned packet_t is valid until +// the next call to plm_demux_decode() or until the demuxer is destroyed. + +plm_packet_t *plm_demux_decode(plm_demux_t *self); + + + +// ----------------------------------------------------------------------------- +// plm_video public API +// Decode MPEG1 Video ("mpeg1") data into raw YCrCb frames + + +// Create a video decoder with a plm_buffer as source. + +plm_video_t *plm_video_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done); + + +// Destroy a video decoder and free all data. + +void plm_video_destroy(plm_video_t *self); + + +// Get whether a sequence header was found and we can accurately report on +// dimensions and framerate. + +int plm_video_has_header(plm_video_t *self); + + +// Get the framerate in frames per second. + +double plm_video_get_framerate(plm_video_t *self); + + +// Get the display width/height. + +int plm_video_get_width(plm_video_t *self); +int plm_video_get_height(plm_video_t *self); + + +// Set "no delay" mode. When enabled, the decoder assumes that the video does +// *not* contain any B-Frames. This is useful for reducing lag when streaming. +// The default is FALSE. + +void plm_video_set_no_delay(plm_video_t *self, int no_delay); + + +// Get the current internal time in seconds. + +double plm_video_get_time(plm_video_t *self); + + +// Set the current internal time in seconds. This is only useful when you +// manipulate the underlying video buffer and want to enforce a correct +// timestamps. + +void plm_video_set_time(plm_video_t *self, double time); + + +// Rewind the internal buffer. See plm_buffer_rewind(). + +void plm_video_rewind(plm_video_t *self); + + +// Get whether the file has ended. This will be cleared on rewind. + +int plm_video_has_ended(plm_video_t *self); + + +// Decode and return one frame of video and advance the internal time by +// 1/framerate seconds. The returned frame_t is valid until the next call of +// plm_video_decode() or until the video decoder is destroyed. + +plm_frame_t *plm_video_decode(plm_video_t *self); + + +// Convert the YCrCb data of a frame into interleaved R G B data. The stride +// specifies the width in bytes of the destination buffer. I.e. the number of +// bytes from one line to the next. The stride must be at least +// (frame->width * bytes_per_pixel). The buffer pointed to by *dest must have a +// size of at least (stride * frame->height). +// Note that the alpha component of the dest buffer is always left untouched. + +void plm_frame_to_rgb(plm_frame_t *frame, uint8_t *dest, int stride); +void plm_frame_to_bgr(plm_frame_t *frame, uint8_t *dest, int stride); +void plm_frame_to_rgba(plm_frame_t *frame, uint8_t *dest, int stride); +void plm_frame_to_bgra(plm_frame_t *frame, uint8_t *dest, int stride); +void plm_frame_to_argb(plm_frame_t *frame, uint8_t *dest, int stride); +void plm_frame_to_abgr(plm_frame_t *frame, uint8_t *dest, int stride); + + +// ----------------------------------------------------------------------------- +// plm_audio public API +// Decode MPEG-1 Audio Layer II ("mp2") data into raw samples + + +// Create an audio decoder with a plm_buffer as source. + +plm_audio_t *plm_audio_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done); + + +// Destroy an audio decoder and free all data. + +void plm_audio_destroy(plm_audio_t *self); + + +// Get whether a frame header was found and we can accurately report on +// samplerate. + +int plm_audio_has_header(plm_audio_t *self); + + +// Get the samplerate in samples per second. + +int plm_audio_get_samplerate(plm_audio_t *self); + + +// Get the current internal time in seconds. + +double plm_audio_get_time(plm_audio_t *self); + + +// Set the current internal time in seconds. This is only useful when you +// manipulate the underlying video buffer and want to enforce a correct +// timestamps. + +void plm_audio_set_time(plm_audio_t *self, double time); + + +// Rewind the internal buffer. See plm_buffer_rewind(). + +void plm_audio_rewind(plm_audio_t *self); + + +// Get whether the file has ended. This will be cleared on rewind. + +int plm_audio_has_ended(plm_audio_t *self); + + +// Decode and return one "frame" of audio and advance the internal time by +// (PLM_AUDIO_SAMPLES_PER_FRAME/samplerate) seconds. The returned samples_t +// is valid until the next call of plm_audio_decode() or until the audio +// decoder is destroyed. + +plm_samples_t *plm_audio_decode(plm_audio_t *self); + + + +#ifdef __cplusplus +} +#endif + +#endif // PL_MPEG_H + + + + + +// ----------------------------------------------------------------------------- +// ----------------------------------------------------------------------------- +// IMPLEMENTATION + +#ifdef PL_MPEG_IMPLEMENTATION + +#include <string.h> +#include <stdlib.h> + +#ifndef TRUE +#define TRUE 1 +#define FALSE 0 +#endif + +#define PLM_UNUSED(expr) (void)(expr) + + +// ----------------------------------------------------------------------------- +// plm (high-level interface) implementation + +typedef struct plm_t { + plm_demux_t *demux; + double time; + int has_ended; + int loop; + int has_decoders; + + int video_enabled; + int video_packet_type; + plm_buffer_t *video_buffer; + plm_video_t *video_decoder; + + int audio_enabled; + int audio_stream_index; + int audio_packet_type; + double audio_lead_time; + plm_buffer_t *audio_buffer; + plm_audio_t *audio_decoder; + + plm_video_decode_callback video_decode_callback; + void *video_decode_callback_user_data; + + plm_audio_decode_callback audio_decode_callback; + void *audio_decode_callback_user_data; +} plm_t; + +int plm_init_decoders(plm_t *self); +void plm_handle_end(plm_t *self); +void plm_read_video_packet(plm_buffer_t *buffer, void *user); +void plm_read_audio_packet(plm_buffer_t *buffer, void *user); +void plm_read_packets(plm_t *self, int requested_type); + +plm_t *plm_create_with_filename(const char *filename) { + plm_buffer_t *buffer = plm_buffer_create_with_filename(filename); + if (!buffer) { + return NULL; + } + return plm_create_with_buffer(buffer, TRUE); +} + +plm_t *plm_create_with_file(FILE *fh, int close_when_done) { + plm_buffer_t *buffer = plm_buffer_create_with_file(fh, close_when_done); + return plm_create_with_buffer(buffer, TRUE); +} + +plm_t *plm_create_with_memory(uint8_t *bytes, size_t length, int free_when_done) { + plm_buffer_t *buffer = plm_buffer_create_with_memory(bytes, length, free_when_done); + return plm_create_with_buffer(buffer, TRUE); +} + +plm_t *plm_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done) { + plm_t *self = (plm_t *)malloc(sizeof(plm_t)); + memset(self, 0, sizeof(plm_t)); + + self->demux = plm_demux_create(buffer, destroy_when_done); + self->video_enabled = TRUE; + self->audio_enabled = TRUE; + plm_init_decoders(self); + + return self; +} + +int plm_init_decoders(plm_t *self) { + if (self->has_decoders) { + return TRUE; + } + + if (!plm_demux_has_headers(self->demux)) { + return FALSE; + } + + if (plm_demux_get_num_video_streams(self->demux) > 0) { + if (self->video_enabled) { + self->video_packet_type = PLM_DEMUX_PACKET_VIDEO_1; + } + self->video_buffer = plm_buffer_create_with_capacity(PLM_BUFFER_DEFAULT_SIZE); + plm_buffer_set_load_callback(self->video_buffer, plm_read_video_packet, self); + } + + if (plm_demux_get_num_audio_streams(self->demux) > 0) { + if (self->audio_enabled) { + self->audio_packet_type = PLM_DEMUX_PACKET_AUDIO_1 + self->audio_stream_index; + } + self->audio_buffer = plm_buffer_create_with_capacity(PLM_BUFFER_DEFAULT_SIZE); + plm_buffer_set_load_callback(self->audio_buffer, plm_read_audio_packet, self); + } + + if (self->video_buffer) { + self->video_decoder = plm_video_create_with_buffer(self->video_buffer, TRUE); + } + + if (self->audio_buffer) { + self->audio_decoder = plm_audio_create_with_buffer(self->audio_buffer, TRUE); + } + + self->has_decoders = TRUE; + return TRUE; +} + +void plm_destroy(plm_t *self) { + if (self->video_decoder) { + plm_video_destroy(self->video_decoder); + } + if (self->audio_decoder) { + plm_audio_destroy(self->audio_decoder); + } + + plm_demux_destroy(self->demux); + free(self); +} + +int plm_get_audio_enabled(plm_t *self) { + return self->audio_enabled; +} + +int plm_has_headers(plm_t *self) { + if (!plm_demux_has_headers(self->demux)) { + return FALSE; + } + + if (!plm_init_decoders(self)) { + return FALSE; + } + + if ( + (self->video_decoder && !plm_video_has_header(self->video_decoder)) || + (self->audio_decoder && !plm_audio_has_header(self->audio_decoder)) + ) { + return FALSE; + } + + return TRUE; +} + +void plm_set_audio_enabled(plm_t *self, int enabled) { + self->audio_enabled = enabled; + + if (!enabled) { + self->audio_packet_type = 0; + return; + } + + self->audio_packet_type = (plm_init_decoders(self) && self->audio_decoder) + ? PLM_DEMUX_PACKET_AUDIO_1 + self->audio_stream_index + : 0; +} + +void plm_set_audio_stream(plm_t *self, int stream_index) { + if (stream_index < 0 || stream_index > 3) { + return; + } + self->audio_stream_index = stream_index; + + // Set the correct audio_packet_type + plm_set_audio_enabled(self, self->audio_enabled); +} + +int plm_get_video_enabled(plm_t *self) { + return self->video_enabled; +} + +void plm_set_video_enabled(plm_t *self, int enabled) { + self->video_enabled = enabled; + + if (!enabled) { + self->video_packet_type = 0; + return; + } + + self->video_packet_type = (plm_init_decoders(self) && self->video_decoder) + ? PLM_DEMUX_PACKET_VIDEO_1 + : 0; +} + +int plm_get_num_video_streams(plm_t *self) { + return plm_demux_get_num_video_streams(self->demux); +} + +int plm_get_width(plm_t *self) { + return (plm_init_decoders(self) && self->video_decoder) + ? plm_video_get_width(self->video_decoder) + : 0; +} + +int plm_get_height(plm_t *self) { + return (plm_init_decoders(self) && self->video_decoder) + ? plm_video_get_height(self->video_decoder) + : 0; +} + +double plm_get_framerate(plm_t *self) { + return (plm_init_decoders(self) && self->video_decoder) + ? plm_video_get_framerate(self->video_decoder) + : 0; +} + +int plm_get_num_audio_streams(plm_t *self) { + return plm_demux_get_num_audio_streams(self->demux); +} + +int plm_get_samplerate(plm_t *self) { + return (plm_init_decoders(self) && self->audio_decoder) + ? plm_audio_get_samplerate(self->audio_decoder) + : 0; +} + +double plm_get_audio_lead_time(plm_t *self) { + return self->audio_lead_time; +} + +void plm_set_audio_lead_time(plm_t *self, double lead_time) { + self->audio_lead_time = lead_time; +} + +double plm_get_time(plm_t *self) { + return self->time; +} + +double plm_get_duration(plm_t *self) { + return plm_demux_get_duration(self->demux, PLM_DEMUX_PACKET_VIDEO_1); +} + +void plm_rewind(plm_t *self) { + if (self->video_decoder) { + plm_video_rewind(self->video_decoder); + } + + if (self->audio_decoder) { + plm_audio_rewind(self->audio_decoder); + } + + plm_demux_rewind(self->demux); + self->time = 0; +} + +int plm_get_loop(plm_t *self) { + return self->loop; +} + +void plm_set_loop(plm_t *self, int loop) { + self->loop = loop; +} + +int plm_has_ended(plm_t *self) { + return self->has_ended; +} + +void plm_set_video_decode_callback(plm_t *self, plm_video_decode_callback fp, void *user) { + self->video_decode_callback = fp; + self->video_decode_callback_user_data = user; +} + +void plm_set_audio_decode_callback(plm_t *self, plm_audio_decode_callback fp, void *user) { + self->audio_decode_callback = fp; + self->audio_decode_callback_user_data = user; +} + +void plm_decode(plm_t *self, double tick) { + if (!plm_init_decoders(self)) { + return; + } + + int decode_video = (self->video_decode_callback && self->video_packet_type); + int decode_audio = (self->audio_decode_callback && self->audio_packet_type); + + if (!decode_video && !decode_audio) { + // Nothing to do here + return; + } + + int did_decode = FALSE; + int decode_video_failed = FALSE; + int decode_audio_failed = FALSE; + + double video_target_time = self->time + tick; + double audio_target_time = self->time + tick + self->audio_lead_time; + + do { + did_decode = FALSE; + + if (decode_video && plm_video_get_time(self->video_decoder) < video_target_time) { + plm_frame_t *frame = plm_video_decode(self->video_decoder); + if (frame) { + self->video_decode_callback(self, frame, self->video_decode_callback_user_data); + did_decode = TRUE; + } + else { + decode_video_failed = TRUE; + } + } + + if (decode_audio && plm_audio_get_time(self->audio_decoder) < audio_target_time) { + plm_samples_t *samples = plm_audio_decode(self->audio_decoder); + if (samples) { + self->audio_decode_callback(self, samples, self->audio_decode_callback_user_data); + did_decode = TRUE; + } + else { + decode_audio_failed = TRUE; + } + } + } while (did_decode); + + // Did all sources we wanted to decode fail and the demuxer is at the end? + if ( + (!decode_video || decode_video_failed) && + (!decode_audio || decode_audio_failed) && + plm_demux_has_ended(self->demux) + ) { + plm_handle_end(self); + return; + } + + self->time += tick; +} + +plm_frame_t *plm_decode_video(plm_t *self) { + if (!plm_init_decoders(self)) { + return NULL; + } + + if (!self->video_packet_type) { + return NULL; + } + + plm_frame_t *frame = plm_video_decode(self->video_decoder); + if (frame) { + self->time = frame->time; + } + else if (plm_demux_has_ended(self->demux)) { + plm_handle_end(self); + } + return frame; +} + +plm_samples_t *plm_decode_audio(plm_t *self) { + if (!plm_init_decoders(self)) { + return NULL; + } + + if (!self->audio_packet_type) { + return NULL; + } + + plm_samples_t *samples = plm_audio_decode(self->audio_decoder); + if (samples) { + self->time = samples->time; + } + else if (plm_demux_has_ended(self->demux)) { + plm_handle_end(self); + } + return samples; +} + +void plm_handle_end(plm_t *self) { + if (self->loop) { + plm_rewind(self); + } + else { + self->has_ended = TRUE; + } +} + +void plm_read_video_packet(plm_buffer_t *buffer, void *user) { + PLM_UNUSED(buffer); + plm_t *self = (plm_t *)user; + plm_read_packets(self, self->video_packet_type); +} + +void plm_read_audio_packet(plm_buffer_t *buffer, void *user) { + PLM_UNUSED(buffer); + plm_t *self = (plm_t *)user; + plm_read_packets(self, self->audio_packet_type); +} + +void plm_read_packets(plm_t *self, int requested_type) { + plm_packet_t *packet; + while ((packet = plm_demux_decode(self->demux))) { + if (packet->type == self->video_packet_type) { + plm_buffer_write(self->video_buffer, packet->data, packet->length); + } + else if (packet->type == self->audio_packet_type) { + plm_buffer_write(self->audio_buffer, packet->data, packet->length); + } + + if (packet->type == requested_type) { + return; + } + } + + if (plm_demux_has_ended(self->demux)) { + if (self->video_buffer) { + plm_buffer_signal_end(self->video_buffer); + } + if (self->audio_buffer) { + plm_buffer_signal_end(self->audio_buffer); + } + } +} + +plm_frame_t *plm_seek_frame(plm_t *self, double time, int seek_exact) { + if (!plm_init_decoders(self)) { + return NULL; + } + + if (!self->video_packet_type) { + return NULL; + } + + int type = self->video_packet_type; + + double start_time = plm_demux_get_start_time(self->demux, type); + double duration = plm_demux_get_duration(self->demux, type); + + if (time < 0) { + time = 0; + } + else if (time > duration) { + time = duration; + } + + plm_packet_t *packet = plm_demux_seek(self->demux, time, type, TRUE); + if (!packet) { + return NULL; + } + + // Disable writing to the audio buffer while decoding video + int previous_audio_packet_type = self->audio_packet_type; + self->audio_packet_type = 0; + + // Clear video buffer and decode the found packet + plm_video_rewind(self->video_decoder); + plm_video_set_time(self->video_decoder, packet->pts - start_time); + plm_buffer_write(self->video_buffer, packet->data, packet->length); + plm_frame_t *frame = plm_video_decode(self->video_decoder); + + // If we want to seek to an exact frame, we have to decode all frames + // on top of the intra frame we just jumped to. + if (seek_exact) { + while (frame && frame->time < time) { + frame = plm_video_decode(self->video_decoder); + } + } + + // Enable writing to the audio buffer again? + self->audio_packet_type = previous_audio_packet_type; + + if (frame) { + self->time = frame->time; + } + + self->has_ended = FALSE; + return frame; +} + +int plm_seek(plm_t *self, double time, int seek_exact) { + plm_frame_t *frame = plm_seek_frame(self, time, seek_exact); + + if (!frame) { + return FALSE; + } + + if (self->video_decode_callback) { + self->video_decode_callback(self, frame, self->video_decode_callback_user_data); + } + + // If audio is not enabled we are done here. + if (!self->audio_packet_type) { + return TRUE; + } + + // Sync up Audio. This demuxes more packets until the first audio packet + // with a PTS greater than the current time is found. plm_decode() is then + // called to decode enough audio data to satisfy the audio_lead_time. + + double start_time = plm_demux_get_start_time(self->demux, self->video_packet_type); + plm_audio_rewind(self->audio_decoder); + + plm_packet_t *packet = NULL; + while ((packet = plm_demux_decode(self->demux))) { + if (packet->type == self->video_packet_type) { + plm_buffer_write(self->video_buffer, packet->data, packet->length); + } + else if ( + packet->type == self->audio_packet_type && + packet->pts - start_time > self->time + ) { + plm_audio_set_time(self->audio_decoder, packet->pts - start_time); + plm_buffer_write(self->audio_buffer, packet->data, packet->length); + plm_decode(self, 0); + break; + } + } + + return TRUE; +} + + + +// ----------------------------------------------------------------------------- +// plm_buffer implementation + +enum plm_buffer_mode { + PLM_BUFFER_MODE_FILE, + PLM_BUFFER_MODE_FIXED_MEM, + PLM_BUFFER_MODE_RING, + PLM_BUFFER_MODE_APPEND +}; + +typedef struct plm_buffer_t { + size_t bit_index; + size_t capacity; + size_t length; + size_t total_size; + int discard_read_bytes; + int has_ended; + int free_when_done; + int close_when_done; + FILE *fh; + plm_buffer_load_callback load_callback; + void *load_callback_user_data; + uint8_t *bytes; + enum plm_buffer_mode mode; +} plm_buffer_t; + +typedef struct { + int16_t index; + int16_t value; +} plm_vlc_t; + +typedef struct { + int16_t index; + uint16_t value; +} plm_vlc_uint_t; + + +void plm_buffer_seek(plm_buffer_t *self, size_t pos); +size_t plm_buffer_tell(plm_buffer_t *self); +void plm_buffer_discard_read_bytes(plm_buffer_t *self); +void plm_buffer_load_file_callback(plm_buffer_t *self, void *user); + +int plm_buffer_has(plm_buffer_t *self, size_t count); +int plm_buffer_read(plm_buffer_t *self, int count); +void plm_buffer_align(plm_buffer_t *self); +void plm_buffer_skip(plm_buffer_t *self, size_t count); +int plm_buffer_skip_bytes(plm_buffer_t *self, uint8_t v); +int plm_buffer_next_start_code(plm_buffer_t *self); +int plm_buffer_find_start_code(plm_buffer_t *self, int code); +int plm_buffer_no_start_code(plm_buffer_t *self); +int16_t plm_buffer_read_vlc(plm_buffer_t *self, const plm_vlc_t *table); +uint16_t plm_buffer_read_vlc_uint(plm_buffer_t *self, const plm_vlc_uint_t *table); + +plm_buffer_t *plm_buffer_create_with_filename(const char *filename) { + FILE *fh = fopen(filename, "rb"); + if (!fh) { + return NULL; + } + return plm_buffer_create_with_file(fh, TRUE); +} + +plm_buffer_t *plm_buffer_create_with_file(FILE *fh, int close_when_done) { + plm_buffer_t *self = plm_buffer_create_with_capacity(PLM_BUFFER_DEFAULT_SIZE); + self->fh = fh; + self->close_when_done = close_when_done; + self->mode = PLM_BUFFER_MODE_FILE; + self->discard_read_bytes = TRUE; + + fseek(self->fh, 0, SEEK_END); + self->total_size = ftell(self->fh); + fseek(self->fh, 0, SEEK_SET); + + plm_buffer_set_load_callback(self, plm_buffer_load_file_callback, NULL); + return self; +} + +plm_buffer_t *plm_buffer_create_with_memory(uint8_t *bytes, size_t length, int free_when_done) { + plm_buffer_t *self = (plm_buffer_t *)malloc(sizeof(plm_buffer_t)); + memset(self, 0, sizeof(plm_buffer_t)); + self->capacity = length; + self->length = length; + self->total_size = length; + self->free_when_done = free_when_done; + self->bytes = bytes; + self->mode = PLM_BUFFER_MODE_FIXED_MEM; + self->discard_read_bytes = FALSE; + return self; +} + +plm_buffer_t *plm_buffer_create_with_capacity(size_t capacity) { + plm_buffer_t *self = (plm_buffer_t *)malloc(sizeof(plm_buffer_t)); + memset(self, 0, sizeof(plm_buffer_t)); + self->capacity = capacity; + self->free_when_done = TRUE; + self->bytes = (uint8_t *)malloc(capacity); + self->mode = PLM_BUFFER_MODE_RING; + self->discard_read_bytes = TRUE; + return self; +} + +plm_buffer_t *plm_buffer_create_for_appending(size_t initial_capacity) { + plm_buffer_t *self = plm_buffer_create_with_capacity(initial_capacity); + self->mode = PLM_BUFFER_MODE_APPEND; + self->discard_read_bytes = FALSE; + return self; +} + +void plm_buffer_destroy(plm_buffer_t *self) { + if (self->fh && self->close_when_done) { + fclose(self->fh); + } + if (self->free_when_done) { + free(self->bytes); + } + free(self); +} + +size_t plm_buffer_get_size(plm_buffer_t *self) { + return (self->mode == PLM_BUFFER_MODE_FILE) + ? self->total_size + : self->length; +} + +size_t plm_buffer_get_remaining(plm_buffer_t *self) { + return self->length - (self->bit_index >> 3); +} + +size_t plm_buffer_write(plm_buffer_t *self, uint8_t *bytes, size_t length) { + if (self->mode == PLM_BUFFER_MODE_FIXED_MEM) { + return 0; + } + + if (self->discard_read_bytes) { + // This should be a ring buffer, but instead it just shifts all unread + // data to the beginning of the buffer and appends new data at the end. + // Seems to be good enough. + + plm_buffer_discard_read_bytes(self); + if (self->mode == PLM_BUFFER_MODE_RING) { + self->total_size = 0; + } + } + + // Do we have to resize to fit the new data? + size_t bytes_available = self->capacity - self->length; + if (bytes_available < length) { + size_t new_size = self->capacity; + do { + new_size *= 2; + } while (new_size - self->length < length); + self->bytes = (uint8_t *)realloc(self->bytes, new_size); + self->capacity = new_size; + } + + memcpy(self->bytes + self->length, bytes, length); + self->length += length; + self->has_ended = FALSE; + return length; +} + +void plm_buffer_signal_end(plm_buffer_t *self) { + self->total_size = self->length; +} + +void plm_buffer_set_load_callback(plm_buffer_t *self, plm_buffer_load_callback fp, void *user) { + self->load_callback = fp; + self->load_callback_user_data = user; +} + +void plm_buffer_rewind(plm_buffer_t *self) { + plm_buffer_seek(self, 0); +} + +void plm_buffer_seek(plm_buffer_t *self, size_t pos) { + self->has_ended = FALSE; + + if (self->mode == PLM_BUFFER_MODE_FILE) { + fseek(self->fh, pos, SEEK_SET); + self->bit_index = 0; + self->length = 0; + } + else if (self->mode == PLM_BUFFER_MODE_RING) { + if (pos != 0) { + // Seeking to non-0 is forbidden for dynamic-mem buffers + return; + } + self->bit_index = 0; + self->length = 0; + self->total_size = 0; + } + else if (pos < self->length) { + self->bit_index = pos << 3; + } +} + +size_t plm_buffer_tell(plm_buffer_t *self) { + return self->mode == PLM_BUFFER_MODE_FILE + ? ftell(self->fh) + (self->bit_index >> 3) - self->length + : self->bit_index >> 3; +} + +void plm_buffer_discard_read_bytes(plm_buffer_t *self) { + size_t byte_pos = self->bit_index >> 3; + if (byte_pos == self->length) { + self->bit_index = 0; + self->length = 0; + } + else if (byte_pos > 0) { + memmove(self->bytes, self->bytes + byte_pos, self->length - byte_pos); + self->bit_index -= byte_pos << 3; + self->length -= byte_pos; + } +} + +void plm_buffer_load_file_callback(plm_buffer_t *self, void *user) { + PLM_UNUSED(user); + + if (self->discard_read_bytes) { + plm_buffer_discard_read_bytes(self); + } + + size_t bytes_available = self->capacity - self->length; + size_t bytes_read = fread(self->bytes + self->length, 1, bytes_available, self->fh); + self->length += bytes_read; + + if (bytes_read == 0) { + self->has_ended = TRUE; + } +} + +int plm_buffer_has_ended(plm_buffer_t *self) { + return self->has_ended; +} + +int plm_buffer_has(plm_buffer_t *self, size_t count) { + if (((self->length << 3) - self->bit_index) >= count) { + return TRUE; + } + + if (self->load_callback) { + self->load_callback(self, self->load_callback_user_data); + + if (((self->length << 3) - self->bit_index) >= count) { + return TRUE; + } + } + + if (self->total_size != 0 && self->length == self->total_size) { + self->has_ended = TRUE; + } + return FALSE; +} + +int plm_buffer_read(plm_buffer_t *self, int count) { + if (!plm_buffer_has(self, count)) { + return 0; + } + + int value = 0; + while (count) { + int current_byte = self->bytes[self->bit_index >> 3]; + + int remaining = 8 - (self->bit_index & 7); // Remaining bits in byte + int read = remaining < count ? remaining : count; // Bits in self run + int shift = remaining - read; + int mask = (0xff >> (8 - read)); + + value = (value << read) | ((current_byte & (mask << shift)) >> shift); + + self->bit_index += read; + count -= read; + } + + return value; +} + +void plm_buffer_align(plm_buffer_t *self) { + self->bit_index = ((self->bit_index + 7) >> 3) << 3; // Align to next byte +} + +void plm_buffer_skip(plm_buffer_t *self, size_t count) { + if (plm_buffer_has(self, count)) { + self->bit_index += count; + } +} + +int plm_buffer_skip_bytes(plm_buffer_t *self, uint8_t v) { + plm_buffer_align(self); + int skipped = 0; + while (plm_buffer_has(self, 8) && self->bytes[self->bit_index >> 3] == v) { + self->bit_index += 8; + skipped++; + } + return skipped; +} + +int plm_buffer_next_start_code(plm_buffer_t *self) { + plm_buffer_align(self); + + while (plm_buffer_has(self, (5 << 3))) { + size_t byte_index = (self->bit_index) >> 3; + if ( + self->bytes[byte_index] == 0x00 && + self->bytes[byte_index + 1] == 0x00 && + self->bytes[byte_index + 2] == 0x01 + ) { + self->bit_index = (byte_index + 4) << 3; + return self->bytes[byte_index + 3]; + } + self->bit_index += 8; + } + return -1; +} + +int plm_buffer_find_start_code(plm_buffer_t *self, int code) { + int current = 0; + while (TRUE) { + current = plm_buffer_next_start_code(self); + if (current == code || current == -1) { + return current; + } + } + return -1; +} + +int plm_buffer_has_start_code(plm_buffer_t *self, int code) { + size_t previous_bit_index = self->bit_index; + int previous_discard_read_bytes = self->discard_read_bytes; + + self->discard_read_bytes = FALSE; + int current = plm_buffer_find_start_code(self, code); + + self->bit_index = previous_bit_index; + self->discard_read_bytes = previous_discard_read_bytes; + return current; +} + +int plm_buffer_no_start_code(plm_buffer_t *self) { + if (!plm_buffer_has(self, (5 << 3))) { + return FALSE; + } + + size_t byte_index = ((self->bit_index + 7) >> 3); + return !( + self->bytes[byte_index] == 0x00 && + self->bytes[byte_index + 1] == 0x00 && + self->bytes[byte_index + 2] == 0x01 + ); +} + +int16_t plm_buffer_read_vlc(plm_buffer_t *self, const plm_vlc_t *table) { + plm_vlc_t state = {0, 0}; + do { + state = table[state.index + plm_buffer_read(self, 1)]; + } while (state.index > 0); + return state.value; +} + +uint16_t plm_buffer_read_vlc_uint(plm_buffer_t *self, const plm_vlc_uint_t *table) { + return (uint16_t)plm_buffer_read_vlc(self, (const plm_vlc_t *)table); +} + + + +// ---------------------------------------------------------------------------- +// plm_demux implementation + +static const int PLM_START_PACK = 0xBA; +static const int PLM_START_END = 0xB9; +static const int PLM_START_SYSTEM = 0xBB; + +typedef struct plm_demux_t { + plm_buffer_t *buffer; + int destroy_buffer_when_done; + double system_clock_ref; + + size_t last_file_size; + double last_decoded_pts; + double start_time; + double duration; + + int start_code; + int has_pack_header; + int has_system_header; + int has_headers; + + int num_audio_streams; + int num_video_streams; + plm_packet_t current_packet; + plm_packet_t next_packet; +} plm_demux_t; + + +void plm_demux_buffer_seek(plm_demux_t *self, size_t pos); +double plm_demux_decode_time(plm_demux_t *self); +plm_packet_t *plm_demux_decode_packet(plm_demux_t *self, int type); +plm_packet_t *plm_demux_get_packet(plm_demux_t *self); + +plm_demux_t *plm_demux_create(plm_buffer_t *buffer, int destroy_when_done) { + plm_demux_t *self = (plm_demux_t *)malloc(sizeof(plm_demux_t)); + memset(self, 0, sizeof(plm_demux_t)); + + self->buffer = buffer; + self->destroy_buffer_when_done = destroy_when_done; + + self->start_time = PLM_PACKET_INVALID_TS; + self->duration = PLM_PACKET_INVALID_TS; + self->start_code = -1; + + plm_demux_has_headers(self); + return self; +} + +void plm_demux_destroy(plm_demux_t *self) { + if (self->destroy_buffer_when_done) { + plm_buffer_destroy(self->buffer); + } + free(self); +} + +int plm_demux_has_headers(plm_demux_t *self) { + if (self->has_headers) { + return TRUE; + } + + // Decode pack header + if (!self->has_pack_header) { + if ( + self->start_code != PLM_START_PACK && + plm_buffer_find_start_code(self->buffer, PLM_START_PACK) == -1 + ) { + return FALSE; + } + + self->start_code = PLM_START_PACK; + if (!plm_buffer_has(self->buffer, 64)) { + return FALSE; + } + self->start_code = -1; + + if (plm_buffer_read(self->buffer, 4) != 0x02) { + return FALSE; + } + + self->system_clock_ref = plm_demux_decode_time(self); + plm_buffer_skip(self->buffer, 1); + plm_buffer_skip(self->buffer, 22); // mux_rate * 50 + plm_buffer_skip(self->buffer, 1); + + self->has_pack_header = TRUE; + } + + // Decode system header + if (!self->has_system_header) { + if ( + self->start_code != PLM_START_SYSTEM && + plm_buffer_find_start_code(self->buffer, PLM_START_SYSTEM) == -1 + ) { + return FALSE; + } + + self->start_code = PLM_START_SYSTEM; + if (!plm_buffer_has(self->buffer, 56)) { + return FALSE; + } + self->start_code = -1; + + plm_buffer_skip(self->buffer, 16); // header_length + plm_buffer_skip(self->buffer, 24); // rate bound + self->num_audio_streams = plm_buffer_read(self->buffer, 6); + plm_buffer_skip(self->buffer, 5); // misc flags + self->num_video_streams = plm_buffer_read(self->buffer, 5); + + self->has_system_header = TRUE; + } + + self->has_headers = TRUE; + return TRUE; +} + +int plm_demux_get_num_video_streams(plm_demux_t *self) { + return plm_demux_has_headers(self) + ? self->num_video_streams + : 0; +} + +int plm_demux_get_num_audio_streams(plm_demux_t *self) { + return plm_demux_has_headers(self) + ? self->num_audio_streams + : 0; +} + +void plm_demux_rewind(plm_demux_t *self) { + plm_buffer_rewind(self->buffer); + self->current_packet.length = 0; + self->next_packet.length = 0; + self->start_code = -1; +} + +int plm_demux_has_ended(plm_demux_t *self) { + return plm_buffer_has_ended(self->buffer); +} + +void plm_demux_buffer_seek(plm_demux_t *self, size_t pos) { + plm_buffer_seek(self->buffer, pos); + self->current_packet.length = 0; + self->next_packet.length = 0; + self->start_code = -1; +} + +double plm_demux_get_start_time(plm_demux_t *self, int type) { + if (self->start_time != PLM_PACKET_INVALID_TS) { + return self->start_time; + } + + int previous_pos = plm_buffer_tell(self->buffer); + int previous_start_code = self->start_code; + + // Find first video PTS + plm_demux_rewind(self); + do { + plm_packet_t *packet = plm_demux_decode(self); + if (!packet) { + break; + } + if (packet->type == type) { + self->start_time = packet->pts; + } + } while (self->start_time == PLM_PACKET_INVALID_TS); + + plm_demux_buffer_seek(self, previous_pos); + self->start_code = previous_start_code; + return self->start_time; +} + +double plm_demux_get_duration(plm_demux_t *self, int type) { + size_t file_size = plm_buffer_get_size(self->buffer); + + if ( + self->duration != PLM_PACKET_INVALID_TS && + self->last_file_size == file_size + ) { + return self->duration; + } + + size_t previous_pos = plm_buffer_tell(self->buffer); + int previous_start_code = self->start_code; + + // Find last video PTS. Start searching 64kb from the end and go further + // back if needed. + long start_range = 64 * 1024; + long max_range = 4096 * 1024; + for (long range = start_range; range <= max_range; range *= 2) { + long seek_pos = file_size - range; + if (seek_pos < 0) { + seek_pos = 0; + range = max_range; // Make sure to bail after this round + } + plm_demux_buffer_seek(self, seek_pos); + self->current_packet.length = 0; + + double last_pts = PLM_PACKET_INVALID_TS; + plm_packet_t *packet = NULL; + while ((packet = plm_demux_decode(self))) { + if (packet->pts != PLM_PACKET_INVALID_TS && packet->type == type) { + last_pts = packet->pts; + } + } + if (last_pts != PLM_PACKET_INVALID_TS) { + self->duration = last_pts - plm_demux_get_start_time(self, type); + break; + } + } + + plm_demux_buffer_seek(self, previous_pos); + self->start_code = previous_start_code; + self->last_file_size = file_size; + return self->duration; +} + +plm_packet_t *plm_demux_seek(plm_demux_t *self, double seek_time, int type, int force_intra) { + if (!plm_demux_has_headers(self)) { + return NULL; + } + + // Using the current time, current byte position and the average bytes per + // second for this file, try to jump to a byte position that hopefully has + // packets containing timestamps within one second before to the desired + // seek_time. + + // If we hit close to the seek_time scan through all packets to find the + // last one (just before the seek_time) containing an intra frame. + // Otherwise we should at least be closer than before. Calculate the bytes + // per second for the jumped range and jump again. + + // The number of retries here is hard-limited to a generous amount. Usually + // the correct range is found after 1--5 jumps, even for files with very + // variable bitrates. If significantly more jumps are needed, there's + // probably something wrong with the file and we just avoid getting into an + // infinite loop. 32 retries should be enough for anybody. + + double duration = plm_demux_get_duration(self, type); + long file_size = plm_buffer_get_size(self->buffer); + long byterate = file_size / duration; + + double cur_time = self->last_decoded_pts; + double scan_span = 1; + + if (seek_time > duration) { + seek_time = duration; + } + else if (seek_time < 0) { + seek_time = 0; + } + seek_time += self->start_time; + + for (int retry = 0; retry < 32; retry++) { + int found_packet_with_pts = FALSE; + int found_packet_in_range = FALSE; + long last_valid_packet_start = -1; + double first_packet_time = PLM_PACKET_INVALID_TS; + + long cur_pos = plm_buffer_tell(self->buffer); + + // Estimate byte offset and jump to it. + long offset = (seek_time - cur_time - scan_span) * byterate; + long seek_pos = cur_pos + offset; + if (seek_pos < 0) { + seek_pos = 0; + } + else if (seek_pos > file_size - 256) { + seek_pos = file_size - 256; + } + + plm_demux_buffer_seek(self, seek_pos); + + // Scan through all packets up to the seek_time to find the last packet + // containing an intra frame. + while (plm_buffer_find_start_code(self->buffer, type) != -1) { + long packet_start = plm_buffer_tell(self->buffer); + plm_packet_t *packet = plm_demux_decode_packet(self, type); + + // Skip packet if it has no PTS + if (!packet || packet->pts == PLM_PACKET_INVALID_TS) { + continue; + } + + // Bail scanning through packets if we hit one that is outside + // seek_time - scan_span. + // We also adjust the cur_time and byterate values here so the next + // iteration can be a bit more precise. + if (packet->pts > seek_time || packet->pts < seek_time - scan_span) { + found_packet_with_pts = TRUE; + byterate = (seek_pos - cur_pos) / (packet->pts - cur_time); + cur_time = packet->pts; + break; + } + + // If we are still here, it means this packet is in close range to + // the seek_time. If this is the first packet for this jump position + // record the PTS. If we later have to back off, when there was no + // intra frame in this range, we can lower the seek_time to not scan + // this range again. + if (!found_packet_in_range) { + found_packet_in_range = TRUE; + first_packet_time = packet->pts; + } + + // Check if this is an intra frame packet. If so, record the buffer + // position of the start of this packet. We want to jump back to it + // later, when we know it's the last intra frame before desired + // seek time. + if (force_intra) { + for (size_t i = 0; i < packet->length - 6; i++) { + // Find the START_PICTURE code + if ( + packet->data[i] == 0x00 && + packet->data[i + 1] == 0x00 && + packet->data[i + 2] == 0x01 && + packet->data[i + 3] == 0x00 + ) { + // Bits 11--13 in the picture header contain the frame + // type, where 1=Intra + if ((packet->data[i + 5] & 0x38) == 8) { + last_valid_packet_start = packet_start; + } + break; + } + } + } + + // If we don't want intra frames, just use the last PTS found. + else { + last_valid_packet_start = packet_start; + } + } + + // If there was at least one intra frame in the range scanned above, + // our search is over. Jump back to the packet and decode it again. + if (last_valid_packet_start != -1) { + plm_demux_buffer_seek(self, last_valid_packet_start); + return plm_demux_decode_packet(self, type); + } + + // If we hit the right range, but still found no intra frame, we have + // to increases the scan_span. This is done exponentially to also handle + // video files with very few intra frames. + else if (found_packet_in_range) { + scan_span *= 2; + seek_time = first_packet_time; + } + + // If we didn't find any packet with a PTS, it probably means we reached + // the end of the file. Estimate byterate and cur_time accordingly. + else if (!found_packet_with_pts) { + byterate = (seek_pos - cur_pos) / (duration - cur_time); + cur_time = duration; + } + } + + return NULL; +} + +plm_packet_t *plm_demux_decode(plm_demux_t *self) { + if (!plm_demux_has_headers(self)) { + return NULL; + } + + if (self->current_packet.length) { + size_t bits_till_next_packet = self->current_packet.length << 3; + if (!plm_buffer_has(self->buffer, bits_till_next_packet)) { + return NULL; + } + plm_buffer_skip(self->buffer, bits_till_next_packet); + self->current_packet.length = 0; + } + + // Pending packet waiting for data? + if (self->next_packet.length) { + return plm_demux_get_packet(self); + } + + // Pending packet waiting for header? + if (self->start_code != -1) { + return plm_demux_decode_packet(self, self->start_code); + } + + do { + self->start_code = plm_buffer_next_start_code(self->buffer); + if ( + self->start_code == PLM_DEMUX_PACKET_VIDEO_1 || + self->start_code == PLM_DEMUX_PACKET_PRIVATE || ( + self->start_code >= PLM_DEMUX_PACKET_AUDIO_1 && + self->start_code <= PLM_DEMUX_PACKET_AUDIO_4 + ) + ) { + return plm_demux_decode_packet(self, self->start_code); + } + } while (self->start_code != -1); + + return NULL; +} + +double plm_demux_decode_time(plm_demux_t *self) { + int64_t clock = plm_buffer_read(self->buffer, 3) << 30; + plm_buffer_skip(self->buffer, 1); + clock |= plm_buffer_read(self->buffer, 15) << 15; + plm_buffer_skip(self->buffer, 1); + clock |= plm_buffer_read(self->buffer, 15); + plm_buffer_skip(self->buffer, 1); + return (double)clock / 90000.0; +} + +plm_packet_t *plm_demux_decode_packet(plm_demux_t *self, int type) { + if (!plm_buffer_has(self->buffer, 16 << 3)) { + return NULL; + } + + self->start_code = -1; + + self->next_packet.type = type; + self->next_packet.length = plm_buffer_read(self->buffer, 16); + self->next_packet.length -= plm_buffer_skip_bytes(self->buffer, 0xff); // stuffing + + // skip P-STD + if (plm_buffer_read(self->buffer, 2) == 0x01) { + plm_buffer_skip(self->buffer, 16); + self->next_packet.length -= 2; + } + + int pts_dts_marker = plm_buffer_read(self->buffer, 2); + if (pts_dts_marker == 0x03) { + self->next_packet.pts = plm_demux_decode_time(self); + self->last_decoded_pts = self->next_packet.pts; + plm_buffer_skip(self->buffer, 40); // skip dts + self->next_packet.length -= 10; + } + else if (pts_dts_marker == 0x02) { + self->next_packet.pts = plm_demux_decode_time(self); + self->last_decoded_pts = self->next_packet.pts; + self->next_packet.length -= 5; + } + else if (pts_dts_marker == 0x00) { + self->next_packet.pts = PLM_PACKET_INVALID_TS; + plm_buffer_skip(self->buffer, 4); + self->next_packet.length -= 1; + } + else { + return NULL; // invalid + } + + return plm_demux_get_packet(self); +} + +plm_packet_t *plm_demux_get_packet(plm_demux_t *self) { + if (!plm_buffer_has(self->buffer, self->next_packet.length << 3)) { + return NULL; + } + + self->current_packet.data = self->buffer->bytes + (self->buffer->bit_index >> 3); + self->current_packet.length = self->next_packet.length; + self->current_packet.type = self->next_packet.type; + self->current_packet.pts = self->next_packet.pts; + + self->next_packet.length = 0; + return &self->current_packet; +} + + + +// ----------------------------------------------------------------------------- +// plm_video implementation + +// Inspired by Java MPEG-1 Video Decoder and Player by Zoltan Korandi +// https://sourceforge.net/projects/javampeg1video/ + +static const int PLM_VIDEO_PICTURE_TYPE_INTRA = 1; +static const int PLM_VIDEO_PICTURE_TYPE_PREDICTIVE = 2; +static const int PLM_VIDEO_PICTURE_TYPE_B = 3; + +static const int PLM_START_SEQUENCE = 0xB3; +static const int PLM_START_SLICE_FIRST = 0x01; +static const int PLM_START_SLICE_LAST = 0xAF; +static const int PLM_START_PICTURE = 0x00; +static const int PLM_START_EXTENSION = 0xB5; +static const int PLM_START_USER_DATA = 0xB2; + +#define PLM_START_IS_SLICE(c) \ + (c >= PLM_START_SLICE_FIRST && c <= PLM_START_SLICE_LAST) + +static const double PLM_VIDEO_PICTURE_RATE[] = { + 0.000, 23.976, 24.000, 25.000, 29.970, 30.000, 50.000, 59.940, + 60.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000 +}; + +static const uint8_t PLM_VIDEO_ZIG_ZAG[] = { + 0, 1, 8, 16, 9, 2, 3, 10, + 17, 24, 32, 25, 18, 11, 4, 5, + 12, 19, 26, 33, 40, 48, 41, 34, + 27, 20, 13, 6, 7, 14, 21, 28, + 35, 42, 49, 56, 57, 50, 43, 36, + 29, 22, 15, 23, 30, 37, 44, 51, + 58, 59, 52, 45, 38, 31, 39, 46, + 53, 60, 61, 54, 47, 55, 62, 63 +}; + +static const uint8_t PLM_VIDEO_INTRA_QUANT_MATRIX[] = { + 8, 16, 19, 22, 26, 27, 29, 34, + 16, 16, 22, 24, 27, 29, 34, 37, + 19, 22, 26, 27, 29, 34, 34, 38, + 22, 22, 26, 27, 29, 34, 37, 40, + 22, 26, 27, 29, 32, 35, 40, 48, + 26, 27, 29, 32, 35, 40, 48, 58, + 26, 27, 29, 34, 38, 46, 56, 69, + 27, 29, 35, 38, 46, 56, 69, 83 +}; + +static const uint8_t PLM_VIDEO_NON_INTRA_QUANT_MATRIX[] = { + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16, + 16, 16, 16, 16, 16, 16, 16, 16 +}; + +static const uint8_t PLM_VIDEO_PREMULTIPLIER_MATRIX[] = { + 32, 44, 42, 38, 32, 25, 17, 9, + 44, 62, 58, 52, 44, 35, 24, 12, + 42, 58, 55, 49, 42, 33, 23, 12, + 38, 52, 49, 44, 38, 30, 20, 10, + 32, 44, 42, 38, 32, 25, 17, 9, + 25, 35, 33, 30, 25, 20, 14, 7, + 17, 24, 23, 20, 17, 14, 9, 5, + 9, 12, 12, 10, 9, 7, 5, 2 +}; + +static const plm_vlc_t PLM_VIDEO_MACROBLOCK_ADDRESS_INCREMENT[] = { + { 1 << 1, 0}, { 0, 1}, // 0: x + { 2 << 1, 0}, { 3 << 1, 0}, // 1: 0x + { 4 << 1, 0}, { 5 << 1, 0}, // 2: 00x + { 0, 3}, { 0, 2}, // 3: 01x + { 6 << 1, 0}, { 7 << 1, 0}, // 4: 000x + { 0, 5}, { 0, 4}, // 5: 001x + { 8 << 1, 0}, { 9 << 1, 0}, // 6: 0000x + { 0, 7}, { 0, 6}, // 7: 0001x + { 10 << 1, 0}, { 11 << 1, 0}, // 8: 0000 0x + { 12 << 1, 0}, { 13 << 1, 0}, // 9: 0000 1x + { 14 << 1, 0}, { 15 << 1, 0}, // 10: 0000 00x + { 16 << 1, 0}, { 17 << 1, 0}, // 11: 0000 01x + { 18 << 1, 0}, { 19 << 1, 0}, // 12: 0000 10x + { 0, 9}, { 0, 8}, // 13: 0000 11x + { -1, 0}, { 20 << 1, 0}, // 14: 0000 000x + { -1, 0}, { 21 << 1, 0}, // 15: 0000 001x + { 22 << 1, 0}, { 23 << 1, 0}, // 16: 0000 010x + { 0, 15}, { 0, 14}, // 17: 0000 011x + { 0, 13}, { 0, 12}, // 18: 0000 100x + { 0, 11}, { 0, 10}, // 19: 0000 101x + { 24 << 1, 0}, { 25 << 1, 0}, // 20: 0000 0001x + { 26 << 1, 0}, { 27 << 1, 0}, // 21: 0000 0011x + { 28 << 1, 0}, { 29 << 1, 0}, // 22: 0000 0100x + { 30 << 1, 0}, { 31 << 1, 0}, // 23: 0000 0101x + { 32 << 1, 0}, { -1, 0}, // 24: 0000 0001 0x + { -1, 0}, { 33 << 1, 0}, // 25: 0000 0001 1x + { 34 << 1, 0}, { 35 << 1, 0}, // 26: 0000 0011 0x + { 36 << 1, 0}, { 37 << 1, 0}, // 27: 0000 0011 1x + { 38 << 1, 0}, { 39 << 1, 0}, // 28: 0000 0100 0x + { 0, 21}, { 0, 20}, // 29: 0000 0100 1x + { 0, 19}, { 0, 18}, // 30: 0000 0101 0x + { 0, 17}, { 0, 16}, // 31: 0000 0101 1x + { 0, 35}, { -1, 0}, // 32: 0000 0001 00x + { -1, 0}, { 0, 34}, // 33: 0000 0001 11x + { 0, 33}, { 0, 32}, // 34: 0000 0011 00x + { 0, 31}, { 0, 30}, // 35: 0000 0011 01x + { 0, 29}, { 0, 28}, // 36: 0000 0011 10x + { 0, 27}, { 0, 26}, // 37: 0000 0011 11x + { 0, 25}, { 0, 24}, // 38: 0000 0100 00x + { 0, 23}, { 0, 22}, // 39: 0000 0100 01x +}; + +static const plm_vlc_t PLM_VIDEO_MACROBLOCK_TYPE_INTRA[] = { + { 1 << 1, 0}, { 0, 0x01}, // 0: x + { -1, 0}, { 0, 0x11}, // 1: 0x +}; + +static const plm_vlc_t PLM_VIDEO_MACROBLOCK_TYPE_PREDICTIVE[] = { + { 1 << 1, 0}, { 0, 0x0a}, // 0: x + { 2 << 1, 0}, { 0, 0x02}, // 1: 0x + { 3 << 1, 0}, { 0, 0x08}, // 2: 00x + { 4 << 1, 0}, { 5 << 1, 0}, // 3: 000x + { 6 << 1, 0}, { 0, 0x12}, // 4: 0000x + { 0, 0x1a}, { 0, 0x01}, // 5: 0001x + { -1, 0}, { 0, 0x11}, // 6: 0000 0x +}; + +static const plm_vlc_t PLM_VIDEO_MACROBLOCK_TYPE_B[] = { + { 1 << 1, 0}, { 2 << 1, 0}, // 0: x + { 3 << 1, 0}, { 4 << 1, 0}, // 1: 0x + { 0, 0x0c}, { 0, 0x0e}, // 2: 1x + { 5 << 1, 0}, { 6 << 1, 0}, // 3: 00x + { 0, 0x04}, { 0, 0x06}, // 4: 01x + { 7 << 1, 0}, { 8 << 1, 0}, // 5: 000x + { 0, 0x08}, { 0, 0x0a}, // 6: 001x + { 9 << 1, 0}, { 10 << 1, 0}, // 7: 0000x + { 0, 0x1e}, { 0, 0x01}, // 8: 0001x + { -1, 0}, { 0, 0x11}, // 9: 0000 0x + { 0, 0x16}, { 0, 0x1a}, // 10: 0000 1x +}; + +static const plm_vlc_t *PLM_VIDEO_MACROBLOCK_TYPE[] = { + NULL, + PLM_VIDEO_MACROBLOCK_TYPE_INTRA, + PLM_VIDEO_MACROBLOCK_TYPE_PREDICTIVE, + PLM_VIDEO_MACROBLOCK_TYPE_B +}; + +static const plm_vlc_t PLM_VIDEO_CODE_BLOCK_PATTERN[] = { + { 1 << 1, 0}, { 2 << 1, 0}, // 0: x + { 3 << 1, 0}, { 4 << 1, 0}, // 1: 0x + { 5 << 1, 0}, { 6 << 1, 0}, // 2: 1x + { 7 << 1, 0}, { 8 << 1, 0}, // 3: 00x + { 9 << 1, 0}, { 10 << 1, 0}, // 4: 01x + { 11 << 1, 0}, { 12 << 1, 0}, // 5: 10x + { 13 << 1, 0}, { 0, 60}, // 6: 11x + { 14 << 1, 0}, { 15 << 1, 0}, // 7: 000x + { 16 << 1, 0}, { 17 << 1, 0}, // 8: 001x + { 18 << 1, 0}, { 19 << 1, 0}, // 9: 010x + { 20 << 1, 0}, { 21 << 1, 0}, // 10: 011x + { 22 << 1, 0}, { 23 << 1, 0}, // 11: 100x + { 0, 32}, { 0, 16}, // 12: 101x + { 0, 8}, { 0, 4}, // 13: 110x + { 24 << 1, 0}, { 25 << 1, 0}, // 14: 0000x + { 26 << 1, 0}, { 27 << 1, 0}, // 15: 0001x + { 28 << 1, 0}, { 29 << 1, 0}, // 16: 0010x + { 30 << 1, 0}, { 31 << 1, 0}, // 17: 0011x + { 0, 62}, { 0, 2}, // 18: 0100x + { 0, 61}, { 0, 1}, // 19: 0101x + { 0, 56}, { 0, 52}, // 20: 0110x + { 0, 44}, { 0, 28}, // 21: 0111x + { 0, 40}, { 0, 20}, // 22: 1000x + { 0, 48}, { 0, 12}, // 23: 1001x + { 32 << 1, 0}, { 33 << 1, 0}, // 24: 0000 0x + { 34 << 1, 0}, { 35 << 1, 0}, // 25: 0000 1x + { 36 << 1, 0}, { 37 << 1, 0}, // 26: 0001 0x + { 38 << 1, 0}, { 39 << 1, 0}, // 27: 0001 1x + { 40 << 1, 0}, { 41 << 1, 0}, // 28: 0010 0x + { 42 << 1, 0}, { 43 << 1, 0}, // 29: 0010 1x + { 0, 63}, { 0, 3}, // 30: 0011 0x + { 0, 36}, { 0, 24}, // 31: 0011 1x + { 44 << 1, 0}, { 45 << 1, 0}, // 32: 0000 00x + { 46 << 1, 0}, { 47 << 1, 0}, // 33: 0000 01x + { 48 << 1, 0}, { 49 << 1, 0}, // 34: 0000 10x + { 50 << 1, 0}, { 51 << 1, 0}, // 35: 0000 11x + { 52 << 1, 0}, { 53 << 1, 0}, // 36: 0001 00x + { 54 << 1, 0}, { 55 << 1, 0}, // 37: 0001 01x + { 56 << 1, 0}, { 57 << 1, 0}, // 38: 0001 10x + { 58 << 1, 0}, { 59 << 1, 0}, // 39: 0001 11x + { 0, 34}, { 0, 18}, // 40: 0010 00x + { 0, 10}, { 0, 6}, // 41: 0010 01x + { 0, 33}, { 0, 17}, // 42: 0010 10x + { 0, 9}, { 0, 5}, // 43: 0010 11x + { -1, 0}, { 60 << 1, 0}, // 44: 0000 000x + { 61 << 1, 0}, { 62 << 1, 0}, // 45: 0000 001x + { 0, 58}, { 0, 54}, // 46: 0000 010x + { 0, 46}, { 0, 30}, // 47: 0000 011x + { 0, 57}, { 0, 53}, // 48: 0000 100x + { 0, 45}, { 0, 29}, // 49: 0000 101x + { 0, 38}, { 0, 26}, // 50: 0000 110x + { 0, 37}, { 0, 25}, // 51: 0000 111x + { 0, 43}, { 0, 23}, // 52: 0001 000x + { 0, 51}, { 0, 15}, // 53: 0001 001x + { 0, 42}, { 0, 22}, // 54: 0001 010x + { 0, 50}, { 0, 14}, // 55: 0001 011x + { 0, 41}, { 0, 21}, // 56: 0001 100x + { 0, 49}, { 0, 13}, // 57: 0001 101x + { 0, 35}, { 0, 19}, // 58: 0001 110x + { 0, 11}, { 0, 7}, // 59: 0001 111x + { 0, 39}, { 0, 27}, // 60: 0000 0001x + { 0, 59}, { 0, 55}, // 61: 0000 0010x + { 0, 47}, { 0, 31}, // 62: 0000 0011x +}; + +static const plm_vlc_t PLM_VIDEO_MOTION[] = { + { 1 << 1, 0}, { 0, 0}, // 0: x + { 2 << 1, 0}, { 3 << 1, 0}, // 1: 0x + { 4 << 1, 0}, { 5 << 1, 0}, // 2: 00x + { 0, 1}, { 0, -1}, // 3: 01x + { 6 << 1, 0}, { 7 << 1, 0}, // 4: 000x + { 0, 2}, { 0, -2}, // 5: 001x + { 8 << 1, 0}, { 9 << 1, 0}, // 6: 0000x + { 0, 3}, { 0, -3}, // 7: 0001x + { 10 << 1, 0}, { 11 << 1, 0}, // 8: 0000 0x + { 12 << 1, 0}, { 13 << 1, 0}, // 9: 0000 1x + { -1, 0}, { 14 << 1, 0}, // 10: 0000 00x + { 15 << 1, 0}, { 16 << 1, 0}, // 11: 0000 01x + { 17 << 1, 0}, { 18 << 1, 0}, // 12: 0000 10x + { 0, 4}, { 0, -4}, // 13: 0000 11x + { -1, 0}, { 19 << 1, 0}, // 14: 0000 001x + { 20 << 1, 0}, { 21 << 1, 0}, // 15: 0000 010x + { 0, 7}, { 0, -7}, // 16: 0000 011x + { 0, 6}, { 0, -6}, // 17: 0000 100x + { 0, 5}, { 0, -5}, // 18: 0000 101x + { 22 << 1, 0}, { 23 << 1, 0}, // 19: 0000 0011x + { 24 << 1, 0}, { 25 << 1, 0}, // 20: 0000 0100x + { 26 << 1, 0}, { 27 << 1, 0}, // 21: 0000 0101x + { 28 << 1, 0}, { 29 << 1, 0}, // 22: 0000 0011 0x + { 30 << 1, 0}, { 31 << 1, 0}, // 23: 0000 0011 1x + { 32 << 1, 0}, { 33 << 1, 0}, // 24: 0000 0100 0x + { 0, 10}, { 0, -10}, // 25: 0000 0100 1x + { 0, 9}, { 0, -9}, // 26: 0000 0101 0x + { 0, 8}, { 0, -8}, // 27: 0000 0101 1x + { 0, 16}, { 0, -16}, // 28: 0000 0011 00x + { 0, 15}, { 0, -15}, // 29: 0000 0011 01x + { 0, 14}, { 0, -14}, // 30: 0000 0011 10x + { 0, 13}, { 0, -13}, // 31: 0000 0011 11x + { 0, 12}, { 0, -12}, // 32: 0000 0100 00x + { 0, 11}, { 0, -11}, // 33: 0000 0100 01x +}; + +static const plm_vlc_t PLM_VIDEO_DCT_SIZE_LUMINANCE[] = { + { 1 << 1, 0}, { 2 << 1, 0}, // 0: x + { 0, 1}, { 0, 2}, // 1: 0x + { 3 << 1, 0}, { 4 << 1, 0}, // 2: 1x + { 0, 0}, { 0, 3}, // 3: 10x + { 0, 4}, { 5 << 1, 0}, // 4: 11x + { 0, 5}, { 6 << 1, 0}, // 5: 111x + { 0, 6}, { 7 << 1, 0}, // 6: 1111x + { 0, 7}, { 8 << 1, 0}, // 7: 1111 1x + { 0, 8}, { -1, 0}, // 8: 1111 11x +}; + +static const plm_vlc_t PLM_VIDEO_DCT_SIZE_CHROMINANCE[] = { + { 1 << 1, 0}, { 2 << 1, 0}, // 0: x + { 0, 0}, { 0, 1}, // 1: 0x + { 0, 2}, { 3 << 1, 0}, // 2: 1x + { 0, 3}, { 4 << 1, 0}, // 3: 11x + { 0, 4}, { 5 << 1, 0}, // 4: 111x + { 0, 5}, { 6 << 1, 0}, // 5: 1111x + { 0, 6}, { 7 << 1, 0}, // 6: 1111 1x + { 0, 7}, { 8 << 1, 0}, // 7: 1111 11x + { 0, 8}, { -1, 0}, // 8: 1111 111x +}; + +static const plm_vlc_t *PLM_VIDEO_DCT_SIZE[] = { + PLM_VIDEO_DCT_SIZE_LUMINANCE, + PLM_VIDEO_DCT_SIZE_CHROMINANCE, + PLM_VIDEO_DCT_SIZE_CHROMINANCE +}; + + +// dct_coeff bitmap: +// 0xff00 run +// 0x00ff level + +// Decoded values are unsigned. Sign bit follows in the stream. + +static const plm_vlc_uint_t PLM_VIDEO_DCT_COEFF[] = { + { 1 << 1, 0}, { 0, 0x0001}, // 0: x + { 2 << 1, 0}, { 3 << 1, 0}, // 1: 0x + { 4 << 1, 0}, { 5 << 1, 0}, // 2: 00x + { 6 << 1, 0}, { 0, 0x0101}, // 3: 01x + { 7 << 1, 0}, { 8 << 1, 0}, // 4: 000x + { 9 << 1, 0}, { 10 << 1, 0}, // 5: 001x + { 0, 0x0002}, { 0, 0x0201}, // 6: 010x + { 11 << 1, 0}, { 12 << 1, 0}, // 7: 0000x + { 13 << 1, 0}, { 14 << 1, 0}, // 8: 0001x + { 15 << 1, 0}, { 0, 0x0003}, // 9: 0010x + { 0, 0x0401}, { 0, 0x0301}, // 10: 0011x + { 16 << 1, 0}, { 0, 0xffff}, // 11: 0000 0x + { 17 << 1, 0}, { 18 << 1, 0}, // 12: 0000 1x + { 0, 0x0701}, { 0, 0x0601}, // 13: 0001 0x + { 0, 0x0102}, { 0, 0x0501}, // 14: 0001 1x + { 19 << 1, 0}, { 20 << 1, 0}, // 15: 0010 0x + { 21 << 1, 0}, { 22 << 1, 0}, // 16: 0000 00x + { 0, 0x0202}, { 0, 0x0901}, // 17: 0000 10x + { 0, 0x0004}, { 0, 0x0801}, // 18: 0000 11x + { 23 << 1, 0}, { 24 << 1, 0}, // 19: 0010 00x + { 25 << 1, 0}, { 26 << 1, 0}, // 20: 0010 01x + { 27 << 1, 0}, { 28 << 1, 0}, // 21: 0000 000x + { 29 << 1, 0}, { 30 << 1, 0}, // 22: 0000 001x + { 0, 0x0d01}, { 0, 0x0006}, // 23: 0010 000x + { 0, 0x0c01}, { 0, 0x0b01}, // 24: 0010 001x + { 0, 0x0302}, { 0, 0x0103}, // 25: 0010 010x + { 0, 0x0005}, { 0, 0x0a01}, // 26: 0010 011x + { 31 << 1, 0}, { 32 << 1, 0}, // 27: 0000 0000x + { 33 << 1, 0}, { 34 << 1, 0}, // 28: 0000 0001x + { 35 << 1, 0}, { 36 << 1, 0}, // 29: 0000 0010x + { 37 << 1, 0}, { 38 << 1, 0}, // 30: 0000 0011x + { 39 << 1, 0}, { 40 << 1, 0}, // 31: 0000 0000 0x + { 41 << 1, 0}, { 42 << 1, 0}, // 32: 0000 0000 1x + { 43 << 1, 0}, { 44 << 1, 0}, // 33: 0000 0001 0x + { 45 << 1, 0}, { 46 << 1, 0}, // 34: 0000 0001 1x + { 0, 0x1001}, { 0, 0x0502}, // 35: 0000 0010 0x + { 0, 0x0007}, { 0, 0x0203}, // 36: 0000 0010 1x + { 0, 0x0104}, { 0, 0x0f01}, // 37: 0000 0011 0x + { 0, 0x0e01}, { 0, 0x0402}, // 38: 0000 0011 1x + { 47 << 1, 0}, { 48 << 1, 0}, // 39: 0000 0000 00x + { 49 << 1, 0}, { 50 << 1, 0}, // 40: 0000 0000 01x + { 51 << 1, 0}, { 52 << 1, 0}, // 41: 0000 0000 10x + { 53 << 1, 0}, { 54 << 1, 0}, // 42: 0000 0000 11x + { 55 << 1, 0}, { 56 << 1, 0}, // 43: 0000 0001 00x + { 57 << 1, 0}, { 58 << 1, 0}, // 44: 0000 0001 01x + { 59 << 1, 0}, { 60 << 1, 0}, // 45: 0000 0001 10x + { 61 << 1, 0}, { 62 << 1, 0}, // 46: 0000 0001 11x + { -1, 0}, { 63 << 1, 0}, // 47: 0000 0000 000x + { 64 << 1, 0}, { 65 << 1, 0}, // 48: 0000 0000 001x + { 66 << 1, 0}, { 67 << 1, 0}, // 49: 0000 0000 010x + { 68 << 1, 0}, { 69 << 1, 0}, // 50: 0000 0000 011x + { 70 << 1, 0}, { 71 << 1, 0}, // 51: 0000 0000 100x + { 72 << 1, 0}, { 73 << 1, 0}, // 52: 0000 0000 101x + { 74 << 1, 0}, { 75 << 1, 0}, // 53: 0000 0000 110x + { 76 << 1, 0}, { 77 << 1, 0}, // 54: 0000 0000 111x + { 0, 0x000b}, { 0, 0x0802}, // 55: 0000 0001 000x + { 0, 0x0403}, { 0, 0x000a}, // 56: 0000 0001 001x + { 0, 0x0204}, { 0, 0x0702}, // 57: 0000 0001 010x + { 0, 0x1501}, { 0, 0x1401}, // 58: 0000 0001 011x + { 0, 0x0009}, { 0, 0x1301}, // 59: 0000 0001 100x + { 0, 0x1201}, { 0, 0x0105}, // 60: 0000 0001 101x + { 0, 0x0303}, { 0, 0x0008}, // 61: 0000 0001 110x + { 0, 0x0602}, { 0, 0x1101}, // 62: 0000 0001 111x + { 78 << 1, 0}, { 79 << 1, 0}, // 63: 0000 0000 0001x + { 80 << 1, 0}, { 81 << 1, 0}, // 64: 0000 0000 0010x + { 82 << 1, 0}, { 83 << 1, 0}, // 65: 0000 0000 0011x + { 84 << 1, 0}, { 85 << 1, 0}, // 66: 0000 0000 0100x + { 86 << 1, 0}, { 87 << 1, 0}, // 67: 0000 0000 0101x + { 88 << 1, 0}, { 89 << 1, 0}, // 68: 0000 0000 0110x + { 90 << 1, 0}, { 91 << 1, 0}, // 69: 0000 0000 0111x + { 0, 0x0a02}, { 0, 0x0902}, // 70: 0000 0000 1000x + { 0, 0x0503}, { 0, 0x0304}, // 71: 0000 0000 1001x + { 0, 0x0205}, { 0, 0x0107}, // 72: 0000 0000 1010x + { 0, 0x0106}, { 0, 0x000f}, // 73: 0000 0000 1011x + { 0, 0x000e}, { 0, 0x000d}, // 74: 0000 0000 1100x + { 0, 0x000c}, { 0, 0x1a01}, // 75: 0000 0000 1101x + { 0, 0x1901}, { 0, 0x1801}, // 76: 0000 0000 1110x + { 0, 0x1701}, { 0, 0x1601}, // 77: 0000 0000 1111x + { 92 << 1, 0}, { 93 << 1, 0}, // 78: 0000 0000 0001 0x + { 94 << 1, 0}, { 95 << 1, 0}, // 79: 0000 0000 0001 1x + { 96 << 1, 0}, { 97 << 1, 0}, // 80: 0000 0000 0010 0x + { 98 << 1, 0}, { 99 << 1, 0}, // 81: 0000 0000 0010 1x + {100 << 1, 0}, {101 << 1, 0}, // 82: 0000 0000 0011 0x + {102 << 1, 0}, {103 << 1, 0}, // 83: 0000 0000 0011 1x + { 0, 0x001f}, { 0, 0x001e}, // 84: 0000 0000 0100 0x + { 0, 0x001d}, { 0, 0x001c}, // 85: 0000 0000 0100 1x + { 0, 0x001b}, { 0, 0x001a}, // 86: 0000 0000 0101 0x + { 0, 0x0019}, { 0, 0x0018}, // 87: 0000 0000 0101 1x + { 0, 0x0017}, { 0, 0x0016}, // 88: 0000 0000 0110 0x + { 0, 0x0015}, { 0, 0x0014}, // 89: 0000 0000 0110 1x + { 0, 0x0013}, { 0, 0x0012}, // 90: 0000 0000 0111 0x + { 0, 0x0011}, { 0, 0x0010}, // 91: 0000 0000 0111 1x + {104 << 1, 0}, {105 << 1, 0}, // 92: 0000 0000 0001 00x + {106 << 1, 0}, {107 << 1, 0}, // 93: 0000 0000 0001 01x + {108 << 1, 0}, {109 << 1, 0}, // 94: 0000 0000 0001 10x + {110 << 1, 0}, {111 << 1, 0}, // 95: 0000 0000 0001 11x + { 0, 0x0028}, { 0, 0x0027}, // 96: 0000 0000 0010 00x + { 0, 0x0026}, { 0, 0x0025}, // 97: 0000 0000 0010 01x + { 0, 0x0024}, { 0, 0x0023}, // 98: 0000 0000 0010 10x + { 0, 0x0022}, { 0, 0x0021}, // 99: 0000 0000 0010 11x + { 0, 0x0020}, { 0, 0x010e}, // 100: 0000 0000 0011 00x + { 0, 0x010d}, { 0, 0x010c}, // 101: 0000 0000 0011 01x + { 0, 0x010b}, { 0, 0x010a}, // 102: 0000 0000 0011 10x + { 0, 0x0109}, { 0, 0x0108}, // 103: 0000 0000 0011 11x + { 0, 0x0112}, { 0, 0x0111}, // 104: 0000 0000 0001 000x + { 0, 0x0110}, { 0, 0x010f}, // 105: 0000 0000 0001 001x + { 0, 0x0603}, { 0, 0x1002}, // 106: 0000 0000 0001 010x + { 0, 0x0f02}, { 0, 0x0e02}, // 107: 0000 0000 0001 011x + { 0, 0x0d02}, { 0, 0x0c02}, // 108: 0000 0000 0001 100x + { 0, 0x0b02}, { 0, 0x1f01}, // 109: 0000 0000 0001 101x + { 0, 0x1e01}, { 0, 0x1d01}, // 110: 0000 0000 0001 110x + { 0, 0x1c01}, { 0, 0x1b01}, // 111: 0000 0000 0001 111x +}; + +typedef struct { + int full_px; + int is_set; + int r_size; + int h; + int v; +} plm_video_motion_t; + +typedef struct plm_video_t { + double framerate; + double time; + int frames_decoded; + int width; + int height; + int mb_width; + int mb_height; + int mb_size; + + int luma_width; + int luma_height; + + int chroma_width; + int chroma_height; + + int start_code; + int picture_type; + + plm_video_motion_t motion_forward; + plm_video_motion_t motion_backward; + + int has_sequence_header; + + int quantizer_scale; + int slice_begin; + int macroblock_address; + + int mb_row; + int mb_col; + + int macroblock_type; + int macroblock_intra; + + int dc_predictor[3]; + + plm_buffer_t *buffer; + int destroy_buffer_when_done; + + plm_frame_t frame_current; + plm_frame_t frame_forward; + plm_frame_t frame_backward; + + uint8_t *frames_data; + + int block_data[64]; + uint8_t intra_quant_matrix[64]; + uint8_t non_intra_quant_matrix[64]; + + int has_reference_frame; + int assume_no_b_frames; +} plm_video_t; + +static inline uint8_t plm_clamp(int n) { + if (n > 255) { + n = 255; + } + else if (n < 0) { + n = 0; + } + return n; +} + +int plm_video_decode_sequence_header(plm_video_t *self); +void plm_video_init_frame(plm_video_t *self, plm_frame_t *frame, uint8_t *base); +void plm_video_decode_picture(plm_video_t *self); +void plm_video_decode_slice(plm_video_t *self, int slice); +void plm_video_decode_macroblock(plm_video_t *self); +void plm_video_decode_motion_vectors(plm_video_t *self); +int plm_video_decode_motion_vector(plm_video_t *self, int r_size, int motion); +void plm_video_predict_macroblock(plm_video_t *self); +void plm_video_copy_macroblock(plm_video_t *self, plm_frame_t *s, int motion_h, int motion_v); +void plm_video_interpolate_macroblock(plm_video_t *self, plm_frame_t *s, int motion_h, int motion_v); +void plm_video_process_macroblock(plm_video_t *self, uint8_t *s, uint8_t *d, int mh, int mb, int bs, int interp); +void plm_video_decode_block(plm_video_t *self, int block); +void plm_video_idct(int *block); + +plm_video_t * plm_video_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done) { + plm_video_t *self = (plm_video_t *)malloc(sizeof(plm_video_t)); + memset(self, 0, sizeof(plm_video_t)); + + self->buffer = buffer; + self->destroy_buffer_when_done = destroy_when_done; + + // Attempt to decode the sequence header + self->start_code = plm_buffer_find_start_code(self->buffer, PLM_START_SEQUENCE); + if (self->start_code != -1) { + plm_video_decode_sequence_header(self); + } + return self; +} + +void plm_video_destroy(plm_video_t *self) { + if (self->destroy_buffer_when_done) { + plm_buffer_destroy(self->buffer); + } + + if (self->has_sequence_header) { + free(self->frames_data); + } + + free(self); +} + +double plm_video_get_framerate(plm_video_t *self) { + return plm_video_has_header(self) + ? self->framerate + : 0; +} + +int plm_video_get_width(plm_video_t *self) { + return plm_video_has_header(self) + ? self->width + : 0; +} + +int plm_video_get_height(plm_video_t *self) { + return plm_video_has_header(self) + ? self->height + : 0; +} + +void plm_video_set_no_delay(plm_video_t *self, int no_delay) { + self->assume_no_b_frames = no_delay; +} + +double plm_video_get_time(plm_video_t *self) { + return self->time; +} + +void plm_video_set_time(plm_video_t *self, double time) { + self->frames_decoded = self->framerate * time; + self->time = time; +} + +void plm_video_rewind(plm_video_t *self) { + plm_buffer_rewind(self->buffer); + self->time = 0; + self->frames_decoded = 0; + self->has_reference_frame = FALSE; + self->start_code = -1; +} + +int plm_video_has_ended(plm_video_t *self) { + return plm_buffer_has_ended(self->buffer); +} + +plm_frame_t *plm_video_decode(plm_video_t *self) { + if (!plm_video_has_header(self)) { + return NULL; + } + + plm_frame_t *frame = NULL; + do { + if (self->start_code != PLM_START_PICTURE) { + self->start_code = plm_buffer_find_start_code(self->buffer, PLM_START_PICTURE); + + if (self->start_code == -1) { + // If we reached the end of the file and the previously decoded + // frame was a reference frame, we still have to return it. + if ( + self->has_reference_frame && + !self->assume_no_b_frames && + plm_buffer_has_ended(self->buffer) && ( + self->picture_type == PLM_VIDEO_PICTURE_TYPE_INTRA || + self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE + ) + ) { + self->has_reference_frame = FALSE; + frame = &self->frame_backward; + break; + } + + return NULL; + } + } + + // Make sure we have a full picture in the buffer before attempting to + // decode it. Sadly, this can only be done by seeking for the start code + // of the next picture. Also, if we didn't find the start code for the + // next picture, but the source has ended, we assume that this last + // picture is in the buffer. + if ( + plm_buffer_has_start_code(self->buffer, PLM_START_PICTURE) == -1 && + !plm_buffer_has_ended(self->buffer) + ) { + return NULL; + } + + plm_video_decode_picture(self); + + if (self->assume_no_b_frames) { + frame = &self->frame_backward; + } + else if (self->picture_type == PLM_VIDEO_PICTURE_TYPE_B) { + frame = &self->frame_current; + } + else if (self->has_reference_frame) { + frame = &self->frame_forward; + } + else { + self->has_reference_frame = TRUE; + } + } while (!frame); + + frame->time = self->time; + self->frames_decoded++; + self->time = (double)self->frames_decoded / self->framerate; + + return frame; +} + +int plm_video_has_header(plm_video_t *self) { + if (self->has_sequence_header) { + return TRUE; + } + + if (self->start_code != PLM_START_SEQUENCE) { + self->start_code = plm_buffer_find_start_code(self->buffer, PLM_START_SEQUENCE); + } + if (self->start_code == -1) { + return FALSE; + } + + if (!plm_video_decode_sequence_header(self)) { + return FALSE; + } + + return TRUE; +} + +int plm_video_decode_sequence_header(plm_video_t *self) { + int max_header_size = 64 + 2 * 64 * 8; // 64 bit header + 2x 64 byte matrix + if (!plm_buffer_has(self->buffer, max_header_size)) { + return FALSE; + } + + self->width = plm_buffer_read(self->buffer, 12); + self->height = plm_buffer_read(self->buffer, 12); + + if (self->width <= 0 || self->height <= 0) { + return FALSE; + } + + // Skip pixel aspect ratio + plm_buffer_skip(self->buffer, 4); + + self->framerate = PLM_VIDEO_PICTURE_RATE[plm_buffer_read(self->buffer, 4)]; + + // Skip bit_rate, marker, buffer_size and constrained bit + plm_buffer_skip(self->buffer, 18 + 1 + 10 + 1); + + // Load custom intra quant matrix? + if (plm_buffer_read(self->buffer, 1)) { + for (int i = 0; i < 64; i++) { + int idx = PLM_VIDEO_ZIG_ZAG[i]; + self->intra_quant_matrix[idx] = plm_buffer_read(self->buffer, 8); + } + } + else { + memcpy(self->intra_quant_matrix, PLM_VIDEO_INTRA_QUANT_MATRIX, 64); + } + + // Load custom non intra quant matrix? + if (plm_buffer_read(self->buffer, 1)) { + for (int i = 0; i < 64; i++) { + int idx = PLM_VIDEO_ZIG_ZAG[i]; + self->non_intra_quant_matrix[idx] = plm_buffer_read(self->buffer, 8); + } + } + else { + memcpy(self->non_intra_quant_matrix, PLM_VIDEO_NON_INTRA_QUANT_MATRIX, 64); + } + + self->mb_width = (self->width + 15) >> 4; + self->mb_height = (self->height + 15) >> 4; + self->mb_size = self->mb_width * self->mb_height; + + self->luma_width = self->mb_width << 4; + self->luma_height = self->mb_height << 4; + + self->chroma_width = self->mb_width << 3; + self->chroma_height = self->mb_height << 3; + + + // Allocate one big chunk of data for all 3 frames = 9 planes + size_t luma_plane_size = self->luma_width * self->luma_height; + size_t chroma_plane_size = self->chroma_width * self->chroma_height; + size_t frame_data_size = (luma_plane_size + 2 * chroma_plane_size); + + self->frames_data = (uint8_t*)malloc(frame_data_size * 3); + plm_video_init_frame(self, &self->frame_current, self->frames_data + frame_data_size * 0); + plm_video_init_frame(self, &self->frame_forward, self->frames_data + frame_data_size * 1); + plm_video_init_frame(self, &self->frame_backward, self->frames_data + frame_data_size * 2); + + self->has_sequence_header = TRUE; + return TRUE; +} + +void plm_video_init_frame(plm_video_t *self, plm_frame_t *frame, uint8_t *base) { + size_t luma_plane_size = self->luma_width * self->luma_height; + size_t chroma_plane_size = self->chroma_width * self->chroma_height; + + frame->width = self->width; + frame->height = self->height; + frame->y.width = self->luma_width; + frame->y.height = self->luma_height; + frame->y.data = base; + + frame->cr.width = self->chroma_width; + frame->cr.height = self->chroma_height; + frame->cr.data = base + luma_plane_size; + + frame->cb.width = self->chroma_width; + frame->cb.height = self->chroma_height; + frame->cb.data = base + luma_plane_size + chroma_plane_size; +} + +void plm_video_decode_picture(plm_video_t *self) { + plm_buffer_skip(self->buffer, 10); // skip temporalReference + self->picture_type = plm_buffer_read(self->buffer, 3); + plm_buffer_skip(self->buffer, 16); // skip vbv_delay + + // D frames or unknown coding type + if (self->picture_type <= 0 || self->picture_type > PLM_VIDEO_PICTURE_TYPE_B) { + return; + } + + // Forward full_px, f_code + if ( + self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE || + self->picture_type == PLM_VIDEO_PICTURE_TYPE_B + ) { + self->motion_forward.full_px = plm_buffer_read(self->buffer, 1); + int f_code = plm_buffer_read(self->buffer, 3); + if (f_code == 0) { + // Ignore picture with zero f_code + return; + } + self->motion_forward.r_size = f_code - 1; + } + + // Backward full_px, f_code + if (self->picture_type == PLM_VIDEO_PICTURE_TYPE_B) { + self->motion_backward.full_px = plm_buffer_read(self->buffer, 1); + int f_code = plm_buffer_read(self->buffer, 3); + if (f_code == 0) { + // Ignore picture with zero f_code + return; + } + self->motion_backward.r_size = f_code - 1; + } + + plm_frame_t frame_temp = self->frame_forward; + if ( + self->picture_type == PLM_VIDEO_PICTURE_TYPE_INTRA || + self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE + ) { + self->frame_forward = self->frame_backward; + } + + + // Find first slice start code; skip extension and user data + do { + self->start_code = plm_buffer_next_start_code(self->buffer); + } while ( + self->start_code == PLM_START_EXTENSION || + self->start_code == PLM_START_USER_DATA + ); + + // Decode all slices + while (PLM_START_IS_SLICE(self->start_code)) { + plm_video_decode_slice(self, self->start_code & 0x000000FF); + if (self->macroblock_address >= self->mb_size - 2) { + break; + } + self->start_code = plm_buffer_next_start_code(self->buffer); + } + + // If this is a reference picture rotate the prediction pointers + if ( + self->picture_type == PLM_VIDEO_PICTURE_TYPE_INTRA || + self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE + ) { + self->frame_backward = self->frame_current; + self->frame_current = frame_temp; + } +} + +void plm_video_decode_slice(plm_video_t *self, int slice) { + self->slice_begin = TRUE; + self->macroblock_address = (slice - 1) * self->mb_width - 1; + + // Reset motion vectors and DC predictors + self->motion_backward.h = self->motion_forward.h = 0; + self->motion_backward.v = self->motion_forward.v = 0; + self->dc_predictor[0] = 128; + self->dc_predictor[1] = 128; + self->dc_predictor[2] = 128; + + self->quantizer_scale = plm_buffer_read(self->buffer, 5); + + // Skip extra + while (plm_buffer_read(self->buffer, 1)) { + plm_buffer_skip(self->buffer, 8); + } + + do { + plm_video_decode_macroblock(self); + } while ( + self->macroblock_address < self->mb_size - 1 && + plm_buffer_no_start_code(self->buffer) + ); +} + +void plm_video_decode_macroblock(plm_video_t *self) { + // Decode increment + int increment = 0; + int t = plm_buffer_read_vlc(self->buffer, PLM_VIDEO_MACROBLOCK_ADDRESS_INCREMENT); + + while (t == 34) { + // macroblock_stuffing + t = plm_buffer_read_vlc(self->buffer, PLM_VIDEO_MACROBLOCK_ADDRESS_INCREMENT); + } + while (t == 35) { + // macroblock_escape + increment += 33; + t = plm_buffer_read_vlc(self->buffer, PLM_VIDEO_MACROBLOCK_ADDRESS_INCREMENT); + } + increment += t; + + // Process any skipped macroblocks + if (self->slice_begin) { + // The first increment of each slice is relative to beginning of the + // preverious row, not the preverious macroblock + self->slice_begin = FALSE; + self->macroblock_address += increment; + } + else { + if (self->macroblock_address + increment >= self->mb_size) { + return; // invalid + } + if (increment > 1) { + // Skipped macroblocks reset DC predictors + self->dc_predictor[0] = 128; + self->dc_predictor[1] = 128; + self->dc_predictor[2] = 128; + + // Skipped macroblocks in P-pictures reset motion vectors + if (self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE) { + self->motion_forward.h = 0; + self->motion_forward.v = 0; + } + } + + // Predict skipped macroblocks + while (increment > 1) { + self->macroblock_address++; + self->mb_row = self->macroblock_address / self->mb_width; + self->mb_col = self->macroblock_address % self->mb_width; + + plm_video_predict_macroblock(self); + increment--; + } + self->macroblock_address++; + } + + self->mb_row = self->macroblock_address / self->mb_width; + self->mb_col = self->macroblock_address % self->mb_width; + + if (self->mb_col >= self->mb_width || self->mb_row >= self->mb_height) { + return; // corrupt stream; + } + + // Process the current macroblock + const plm_vlc_t *table = PLM_VIDEO_MACROBLOCK_TYPE[self->picture_type]; + self->macroblock_type = plm_buffer_read_vlc(self->buffer, table); + + self->macroblock_intra = (self->macroblock_type & 0x01); + self->motion_forward.is_set = (self->macroblock_type & 0x08); + self->motion_backward.is_set = (self->macroblock_type & 0x04); + + // Quantizer scale + if ((self->macroblock_type & 0x10) != 0) { + self->quantizer_scale = plm_buffer_read(self->buffer, 5); + } + + if (self->macroblock_intra) { + // Intra-coded macroblocks reset motion vectors + self->motion_backward.h = self->motion_forward.h = 0; + self->motion_backward.v = self->motion_forward.v = 0; + } + else { + // Non-intra macroblocks reset DC predictors + self->dc_predictor[0] = 128; + self->dc_predictor[1] = 128; + self->dc_predictor[2] = 128; + + plm_video_decode_motion_vectors(self); + plm_video_predict_macroblock(self); + } + + // Decode blocks + int cbp = ((self->macroblock_type & 0x02) != 0) + ? plm_buffer_read_vlc(self->buffer, PLM_VIDEO_CODE_BLOCK_PATTERN) + : (self->macroblock_intra ? 0x3f : 0); + + for (int block = 0, mask = 0x20; block < 6; block++) { + if ((cbp & mask) != 0) { + plm_video_decode_block(self, block); + } + mask >>= 1; + } +} + +void plm_video_decode_motion_vectors(plm_video_t *self) { + + // Forward + if (self->motion_forward.is_set) { + int r_size = self->motion_forward.r_size; + self->motion_forward.h = plm_video_decode_motion_vector(self, r_size, self->motion_forward.h); + self->motion_forward.v = plm_video_decode_motion_vector(self, r_size, self->motion_forward.v); + } + else if (self->picture_type == PLM_VIDEO_PICTURE_TYPE_PREDICTIVE) { + // No motion information in P-picture, reset vectors + self->motion_forward.h = 0; + self->motion_forward.v = 0; + } + + if (self->motion_backward.is_set) { + int r_size = self->motion_backward.r_size; + self->motion_backward.h = plm_video_decode_motion_vector(self, r_size, self->motion_backward.h); + self->motion_backward.v = plm_video_decode_motion_vector(self, r_size, self->motion_backward.v); + } +} + +int plm_video_decode_motion_vector(plm_video_t *self, int r_size, int motion) { + int fscale = 1 << r_size; + int m_code = plm_buffer_read_vlc(self->buffer, PLM_VIDEO_MOTION); + int r = 0; + int d; + + if ((m_code != 0) && (fscale != 1)) { + r = plm_buffer_read(self->buffer, r_size); + d = ((abs(m_code) - 1) << r_size) + r + 1; + if (m_code < 0) { + d = -d; + } + } + else { + d = m_code; + } + + motion += d; + if (motion > (fscale << 4) - 1) { + motion -= fscale << 5; + } + else if (motion < ((-fscale) << 4)) { + motion += fscale << 5; + } + + return motion; +} + +void plm_video_predict_macroblock(plm_video_t *self) { + int fw_h = self->motion_forward.h; + int fw_v = self->motion_forward.v; + + if (self->motion_forward.full_px) { + fw_h <<= 1; + fw_v <<= 1; + } + + if (self->picture_type == PLM_VIDEO_PICTURE_TYPE_B) { + int bw_h = self->motion_backward.h; + int bw_v = self->motion_backward.v; + + if (self->motion_backward.full_px) { + bw_h <<= 1; + bw_v <<= 1; + } + + if (self->motion_forward.is_set) { + plm_video_copy_macroblock(self, &self->frame_forward, fw_h, fw_v); + if (self->motion_backward.is_set) { + plm_video_interpolate_macroblock(self, &self->frame_backward, bw_h, bw_v); + } + } + else { + plm_video_copy_macroblock(self, &self->frame_backward, bw_h, bw_v); + } + } + else { + plm_video_copy_macroblock(self, &self->frame_forward, fw_h, fw_v); + } +} + +void plm_video_copy_macroblock(plm_video_t *self, plm_frame_t *s, int motion_h, int motion_v) { + plm_frame_t *d = &self->frame_current; + plm_video_process_macroblock(self, s->y.data, d->y.data, motion_h, motion_v, 16, FALSE); + plm_video_process_macroblock(self, s->cr.data, d->cr.data, motion_h / 2, motion_v / 2, 8, FALSE); + plm_video_process_macroblock(self, s->cb.data, d->cb.data, motion_h / 2, motion_v / 2, 8, FALSE); +} + +void plm_video_interpolate_macroblock(plm_video_t *self, plm_frame_t *s, int motion_h, int motion_v) { + plm_frame_t *d = &self->frame_current; + plm_video_process_macroblock(self, s->y.data, d->y.data, motion_h, motion_v, 16, TRUE); + plm_video_process_macroblock(self, s->cr.data, d->cr.data, motion_h / 2, motion_v / 2, 8, TRUE); + plm_video_process_macroblock(self, s->cb.data, d->cb.data, motion_h / 2, motion_v / 2, 8, TRUE); +} + +#define PLM_BLOCK_SET(DEST, DEST_INDEX, DEST_WIDTH, SOURCE_INDEX, SOURCE_WIDTH, BLOCK_SIZE, OP) do { \ + int dest_scan = DEST_WIDTH - BLOCK_SIZE; \ + int source_scan = SOURCE_WIDTH - BLOCK_SIZE; \ + for (int y = 0; y < BLOCK_SIZE; y++) { \ + for (int x = 0; x < BLOCK_SIZE; x++) { \ + DEST[DEST_INDEX] = OP; \ + SOURCE_INDEX++; DEST_INDEX++; \ + } \ + SOURCE_INDEX += source_scan; \ + DEST_INDEX += dest_scan; \ + }} while(FALSE) + +void plm_video_process_macroblock( + plm_video_t *self, uint8_t *s, uint8_t *d, + int motion_h, int motion_v, int block_size, int interpolate +) { + int dw = self->mb_width * block_size; + + int hp = motion_h >> 1; + int vp = motion_v >> 1; + int odd_h = (motion_h & 1) == 1; + int odd_v = (motion_v & 1) == 1; + + unsigned int si = ((self->mb_row * block_size) + vp) * dw + (self->mb_col * block_size) + hp; + unsigned int di = (self->mb_row * dw + self->mb_col) * block_size; + + unsigned int max_address = (dw * (self->mb_height * block_size - block_size + 1) - block_size); + if (si > max_address || di > max_address) { + return; // corrupt video + } + + #define PLM_MB_CASE(INTERPOLATE, ODD_H, ODD_V, OP) \ + case ((INTERPOLATE << 2) | (ODD_H << 1) | (ODD_V)): \ + PLM_BLOCK_SET(d, di, dw, si, dw, block_size, OP); \ + break + + switch ((interpolate << 2) | (odd_h << 1) | (odd_v)) { + PLM_MB_CASE(0, 0, 0, (s[si])); + PLM_MB_CASE(0, 0, 1, (s[si] + s[si + dw] + 1) >> 1); + PLM_MB_CASE(0, 1, 0, (s[si] + s[si + 1] + 1) >> 1); + PLM_MB_CASE(0, 1, 1, (s[si] + s[si + 1] + s[si + dw] + s[si + dw + 1] + 2) >> 2); + + PLM_MB_CASE(1, 0, 0, (d[di] + (s[si]) + 1) >> 1); + PLM_MB_CASE(1, 0, 1, (d[di] + ((s[si] + s[si + dw] + 1) >> 1) + 1) >> 1); + PLM_MB_CASE(1, 1, 0, (d[di] + ((s[si] + s[si + 1] + 1) >> 1) + 1) >> 1); + PLM_MB_CASE(1, 1, 1, (d[di] + ((s[si] + s[si + 1] + s[si + dw] + s[si + dw + 1] + 2) >> 2) + 1) >> 1); + } + + #undef PLM_MB_CASE +} + +void plm_video_decode_block(plm_video_t *self, int block) { + + int n = 0; + uint8_t *quant_matrix; + + // Decode DC coefficient of intra-coded blocks + if (self->macroblock_intra) { + int predictor; + int dct_size; + + // DC prediction + int plane_index = block > 3 ? block - 3 : 0; + predictor = self->dc_predictor[plane_index]; + dct_size = plm_buffer_read_vlc(self->buffer, PLM_VIDEO_DCT_SIZE[plane_index]); + + // Read DC coeff + if (dct_size > 0) { + int differential = plm_buffer_read(self->buffer, dct_size); + if ((differential & (1 << (dct_size - 1))) != 0) { + self->block_data[0] = predictor + differential; + } + else { + self->block_data[0] = predictor + (-(1 << dct_size) | (differential + 1)); + } + } + else { + self->block_data[0] = predictor; + } + + // Save predictor value + self->dc_predictor[plane_index] = self->block_data[0]; + + // Dequantize + premultiply + self->block_data[0] <<= (3 + 5); + + quant_matrix = self->intra_quant_matrix; + n = 1; + } + else { + quant_matrix = self->non_intra_quant_matrix; + } + + // Decode AC coefficients (+DC for non-intra) + int level = 0; + while (TRUE) { + int run = 0; + uint16_t coeff = plm_buffer_read_vlc_uint(self->buffer, PLM_VIDEO_DCT_COEFF); + + if ((coeff == 0x0001) && (n > 0) && (plm_buffer_read(self->buffer, 1) == 0)) { + // end_of_block + break; + } + if (coeff == 0xffff) { + // escape + run = plm_buffer_read(self->buffer, 6); + level = plm_buffer_read(self->buffer, 8); + if (level == 0) { + level = plm_buffer_read(self->buffer, 8); + } + else if (level == 128) { + level = plm_buffer_read(self->buffer, 8) - 256; + } + else if (level > 128) { + level = level - 256; + } + } + else { + run = coeff >> 8; + level = coeff & 0xff; + if (plm_buffer_read(self->buffer, 1)) { + level = -level; + } + } + + n += run; + if (n < 0 || n >= 64) { + return; // invalid + } + + int de_zig_zagged = PLM_VIDEO_ZIG_ZAG[n]; + n++; + + // Dequantize, oddify, clip + level <<= 1; + if (!self->macroblock_intra) { + level += (level < 0 ? -1 : 1); + } + level = (level * self->quantizer_scale * quant_matrix[de_zig_zagged]) >> 4; + if ((level & 1) == 0) { + level -= level > 0 ? 1 : -1; + } + if (level > 2047) { + level = 2047; + } + else if (level < -2048) { + level = -2048; + } + + // Save premultiplied coefficient + self->block_data[de_zig_zagged] = level * PLM_VIDEO_PREMULTIPLIER_MATRIX[de_zig_zagged]; + } + + // Move block to its place + uint8_t *d; + int dw; + int di; + + if (block < 4) { + d = self->frame_current.y.data; + dw = self->luma_width; + di = (self->mb_row * self->luma_width + self->mb_col) << 4; + if ((block & 1) != 0) { + di += 8; + } + if ((block & 2) != 0) { + di += self->luma_width << 3; + } + } + else { + d = (block == 4) ? self->frame_current.cb.data : self->frame_current.cr.data; + dw = self->chroma_width; + di = ((self->mb_row * self->luma_width) << 2) + (self->mb_col << 3); + } + + int *s = self->block_data; + int si = 0; + if (self->macroblock_intra) { + // Overwrite (no prediction) + if (n == 1) { + int clamped = plm_clamp((s[0] + 128) >> 8); + PLM_BLOCK_SET(d, di, dw, si, 8, 8, clamped); + s[0] = 0; + } + else { + plm_video_idct(s); + PLM_BLOCK_SET(d, di, dw, si, 8, 8, plm_clamp(s[si])); + memset(self->block_data, 0, sizeof(self->block_data)); + } + } + else { + // Add data to the predicted macroblock + if (n == 1) { + int value = (s[0] + 128) >> 8; + PLM_BLOCK_SET(d, di, dw, si, 8, 8, plm_clamp(d[di] + value)); + s[0] = 0; + } + else { + plm_video_idct(s); + PLM_BLOCK_SET(d, di, dw, si, 8, 8, plm_clamp(d[di] + s[si])); + memset(self->block_data, 0, sizeof(self->block_data)); + } + } +} + +void plm_video_idct(int *block) { + int + b1, b3, b4, b6, b7, tmp1, tmp2, m0, + x0, x1, x2, x3, x4, y3, y4, y5, y6, y7; + + // Transform columns + for (int i = 0; i < 8; ++i) { + b1 = block[4 * 8 + i]; + b3 = block[2 * 8 + i] + block[6 * 8 + i]; + b4 = block[5 * 8 + i] - block[3 * 8 + i]; + tmp1 = block[1 * 8 + i] + block[7 * 8 + i]; + tmp2 = block[3 * 8 + i] + block[5 * 8 + i]; + b6 = block[1 * 8 + i] - block[7 * 8 + i]; + b7 = tmp1 + tmp2; + m0 = block[0 * 8 + i]; + x4 = ((b6 * 473 - b4 * 196 + 128) >> 8) - b7; + x0 = x4 - (((tmp1 - tmp2) * 362 + 128) >> 8); + x1 = m0 - b1; + x2 = (((block[2 * 8 + i] - block[6 * 8 + i]) * 362 + 128) >> 8) - b3; + x3 = m0 + b1; + y3 = x1 + x2; + y4 = x3 + b3; + y5 = x1 - x2; + y6 = x3 - b3; + y7 = -x0 - ((b4 * 473 + b6 * 196 + 128) >> 8); + block[0 * 8 + i] = b7 + y4; + block[1 * 8 + i] = x4 + y3; + block[2 * 8 + i] = y5 - x0; + block[3 * 8 + i] = y6 - y7; + block[4 * 8 + i] = y6 + y7; + block[5 * 8 + i] = x0 + y5; + block[6 * 8 + i] = y3 - x4; + block[7 * 8 + i] = y4 - b7; + } + + // Transform rows + for (int i = 0; i < 64; i += 8) { + b1 = block[4 + i]; + b3 = block[2 + i] + block[6 + i]; + b4 = block[5 + i] - block[3 + i]; + tmp1 = block[1 + i] + block[7 + i]; + tmp2 = block[3 + i] + block[5 + i]; + b6 = block[1 + i] - block[7 + i]; + b7 = tmp1 + tmp2; + m0 = block[0 + i]; + x4 = ((b6 * 473 - b4 * 196 + 128) >> 8) - b7; + x0 = x4 - (((tmp1 - tmp2) * 362 + 128) >> 8); + x1 = m0 - b1; + x2 = (((block[2 + i] - block[6 + i]) * 362 + 128) >> 8) - b3; + x3 = m0 + b1; + y3 = x1 + x2; + y4 = x3 + b3; + y5 = x1 - x2; + y6 = x3 - b3; + y7 = -x0 - ((b4 * 473 + b6 * 196 + 128) >> 8); + block[0 + i] = (b7 + y4 + 128) >> 8; + block[1 + i] = (x4 + y3 + 128) >> 8; + block[2 + i] = (y5 - x0 + 128) >> 8; + block[3 + i] = (y6 - y7 + 128) >> 8; + block[4 + i] = (y6 + y7 + 128) >> 8; + block[5 + i] = (x0 + y5 + 128) >> 8; + block[6 + i] = (y3 - x4 + 128) >> 8; + block[7 + i] = (y4 - b7 + 128) >> 8; + } +} + +// YCbCr conversion following the BT.601 standard: +// https://infogalactic.com/info/YCbCr#ITU-R_BT.601_conversion + +#define PLM_PUT_PIXEL(RI, GI, BI, Y_OFFSET, DEST_OFFSET) \ + y = ((frame->y.data[y_index + Y_OFFSET]-16) * 76309) >> 16; \ + dest[d_index + DEST_OFFSET + RI] = plm_clamp(y + r); \ + dest[d_index + DEST_OFFSET + GI] = plm_clamp(y - g); \ + dest[d_index + DEST_OFFSET + BI] = plm_clamp(y + b); + +#define PLM_DEFINE_FRAME_CONVERT_FUNCTION(NAME, BYTES_PER_PIXEL, RI, GI, BI) \ + void NAME(plm_frame_t *frame, uint8_t *dest, int stride) { \ + int cols = frame->width >> 1; \ + int rows = frame->height >> 1; \ + int yw = frame->y.width; \ + int cw = frame->cb.width; \ + for (int row = 0; row < rows; row++) { \ + int c_index = row * cw; \ + int y_index = row * 2 * yw; \ + int d_index = row * 2 * stride; \ + for (int col = 0; col < cols; col++) { \ + int y; \ + int cr = frame->cr.data[c_index] - 128; \ + int cb = frame->cb.data[c_index] - 128; \ + int r = (cr * 104597) >> 16; \ + int g = (cb * 25674 + cr * 53278) >> 16; \ + int b = (cb * 132201) >> 16; \ + PLM_PUT_PIXEL(RI, GI, BI, 0, 0); \ + PLM_PUT_PIXEL(RI, GI, BI, 1, BYTES_PER_PIXEL); \ + PLM_PUT_PIXEL(RI, GI, BI, yw, stride); \ + PLM_PUT_PIXEL(RI, GI, BI, yw + 1, stride + BYTES_PER_PIXEL); \ + c_index += 1; \ + y_index += 2; \ + d_index += 2 * BYTES_PER_PIXEL; \ + } \ + } \ + } + +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_rgb, 3, 0, 1, 2) +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_bgr, 3, 2, 1, 0) +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_rgba, 4, 0, 1, 2) +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_bgra, 4, 2, 1, 0) +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_argb, 4, 1, 2, 3) +PLM_DEFINE_FRAME_CONVERT_FUNCTION(plm_frame_to_abgr, 4, 3, 2, 1) + + +#undef PLM_PUT_PIXEL +#undef PLM_DEFINE_FRAME_CONVERT_FUNCTION + + + +// ----------------------------------------------------------------------------- +// plm_audio implementation + +// Based on kjmp2 by Martin J. Fiedler +// http://keyj.emphy.de/kjmp2/ + +static const int PLM_AUDIO_FRAME_SYNC = 0x7ff; + +static const int PLM_AUDIO_MPEG_2_5 = 0x0; +static const int PLM_AUDIO_MPEG_2 = 0x2; +static const int PLM_AUDIO_MPEG_1 = 0x3; + +static const int PLM_AUDIO_LAYER_III = 0x1; +static const int PLM_AUDIO_LAYER_II = 0x2; +static const int PLM_AUDIO_LAYER_I = 0x3; + +static const int PLM_AUDIO_MODE_STEREO = 0x0; +static const int PLM_AUDIO_MODE_JOINT_STEREO = 0x1; +static const int PLM_AUDIO_MODE_DUAL_CHANNEL = 0x2; +static const int PLM_AUDIO_MODE_MONO = 0x3; + +static const unsigned short PLM_AUDIO_SAMPLE_RATE[] = { + 44100, 48000, 32000, 0, // MPEG-1 + 22050, 24000, 16000, 0 // MPEG-2 +}; + +static const short PLM_AUDIO_BIT_RATE[] = { + 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384, // MPEG-1 + 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160 // MPEG-2 +}; + +static const int PLM_AUDIO_SCALEFACTOR_BASE[] = { + 0x02000000, 0x01965FEA, 0x01428A30 +}; + +static const float PLM_AUDIO_SYNTHESIS_WINDOW[] = { + 0.0, -0.5, -0.5, -0.5, -0.5, -0.5, + -0.5, -1.0, -1.0, -1.0, -1.0, -1.5, + -1.5, -2.0, -2.0, -2.5, -2.5, -3.0, + -3.5, -3.5, -4.0, -4.5, -5.0, -5.5, + -6.5, -7.0, -8.0, -8.5, -9.5, -10.5, + -12.0, -13.0, -14.5, -15.5, -17.5, -19.0, + -20.5, -22.5, -24.5, -26.5, -29.0, -31.5, + -34.0, -36.5, -39.5, -42.5, -45.5, -48.5, + -52.0, -55.5, -58.5, -62.5, -66.0, -69.5, + -73.5, -77.0, -80.5, -84.5, -88.0, -91.5, + -95.0, -98.0, -101.0, -104.0, 106.5, 109.0, + 111.0, 112.5, 113.5, 114.0, 114.0, 113.5, + 112.0, 110.5, 107.5, 104.0, 100.0, 94.5, + 88.5, 81.5, 73.0, 63.5, 53.0, 41.5, + 28.5, 14.5, -1.0, -18.0, -36.0, -55.5, + -76.5, -98.5, -122.0, -147.0, -173.5, -200.5, + -229.5, -259.5, -290.5, -322.5, -355.5, -389.5, + -424.0, -459.5, -495.5, -532.0, -568.5, -605.0, + -641.5, -678.0, -714.0, -749.0, -783.5, -817.0, + -849.0, -879.5, -908.5, -935.0, -959.5, -981.0, + -1000.5, -1016.0, -1028.5, -1037.5, -1042.5, -1043.5, + -1040.0, -1031.5, 1018.5, 1000.0, 976.0, 946.5, + 911.0, 869.5, 822.0, 767.5, 707.0, 640.0, + 565.5, 485.0, 397.0, 302.5, 201.0, 92.5, + -22.5, -144.0, -272.5, -407.0, -547.5, -694.0, + -846.0, -1003.0, -1165.0, -1331.5, -1502.0, -1675.5, + -1852.5, -2031.5, -2212.5, -2394.0, -2576.5, -2758.5, + -2939.5, -3118.5, -3294.5, -3467.5, -3635.5, -3798.5, + -3955.0, -4104.5, -4245.5, -4377.5, -4499.0, -4609.5, + -4708.0, -4792.5, -4863.5, -4919.0, -4958.0, -4979.5, + -4983.0, -4967.5, -4931.5, -4875.0, -4796.0, -4694.5, + -4569.5, -4420.0, -4246.0, -4046.0, -3820.0, -3567.0, + 3287.0, 2979.5, 2644.0, 2280.5, 1888.0, 1467.5, + 1018.5, 541.0, 35.0, -499.0, -1061.0, -1650.0, + -2266.5, -2909.0, -3577.0, -4270.0, -4987.5, -5727.5, + -6490.0, -7274.0, -8077.5, -8899.5, -9739.0, -10594.5, + -11464.5, -12347.0, -13241.0, -14144.5, -15056.0, -15973.5, + -16895.5, -17820.0, -18744.5, -19668.0, -20588.0, -21503.0, + -22410.5, -23308.5, -24195.0, -25068.5, -25926.5, -26767.0, + -27589.0, -28389.0, -29166.5, -29919.0, -30644.5, -31342.0, + -32009.5, -32645.0, -33247.0, -33814.5, -34346.0, -34839.5, + -35295.0, -35710.0, -36084.5, -36417.5, -36707.5, -36954.0, + -37156.5, -37315.0, -37428.0, -37496.0, 37519.0, 37496.0, + 37428.0, 37315.0, 37156.5, 36954.0, 36707.5, 36417.5, + 36084.5, 35710.0, 35295.0, 34839.5, 34346.0, 33814.5, + 33247.0, 32645.0, 32009.5, 31342.0, 30644.5, 29919.0, + 29166.5, 28389.0, 27589.0, 26767.0, 25926.5, 25068.5, + 24195.0, 23308.5, 22410.5, 21503.0, 20588.0, 19668.0, + 18744.5, 17820.0, 16895.5, 15973.5, 15056.0, 14144.5, + 13241.0, 12347.0, 11464.5, 10594.5, 9739.0, 8899.5, + 8077.5, 7274.0, 6490.0, 5727.5, 4987.5, 4270.0, + 3577.0, 2909.0, 2266.5, 1650.0, 1061.0, 499.0, + -35.0, -541.0, -1018.5, -1467.5, -1888.0, -2280.5, + -2644.0, -2979.5, 3287.0, 3567.0, 3820.0, 4046.0, + 4246.0, 4420.0, 4569.5, 4694.5, 4796.0, 4875.0, + 4931.5, 4967.5, 4983.0, 4979.5, 4958.0, 4919.0, + 4863.5, 4792.5, 4708.0, 4609.5, 4499.0, 4377.5, + 4245.5, 4104.5, 3955.0, 3798.5, 3635.5, 3467.5, + 3294.5, 3118.5, 2939.5, 2758.5, 2576.5, 2394.0, + 2212.5, 2031.5, 1852.5, 1675.5, 1502.0, 1331.5, + 1165.0, 1003.0, 846.0, 694.0, 547.5, 407.0, + 272.5, 144.0, 22.5, -92.5, -201.0, -302.5, + -397.0, -485.0, -565.5, -640.0, -707.0, -767.5, + -822.0, -869.5, -911.0, -946.5, -976.0, -1000.0, + 1018.5, 1031.5, 1040.0, 1043.5, 1042.5, 1037.5, + 1028.5, 1016.0, 1000.5, 981.0, 959.5, 935.0, + 908.5, 879.5, 849.0, 817.0, 783.5, 749.0, + 714.0, 678.0, 641.5, 605.0, 568.5, 532.0, + 495.5, 459.5, 424.0, 389.5, 355.5, 322.5, + 290.5, 259.5, 229.5, 200.5, 173.5, 147.0, + 122.0, 98.5, 76.5, 55.5, 36.0, 18.0, + 1.0, -14.5, -28.5, -41.5, -53.0, -63.5, + -73.0, -81.5, -88.5, -94.5, -100.0, -104.0, + -107.5, -110.5, -112.0, -113.5, -114.0, -114.0, + -113.5, -112.5, -111.0, -109.0, 106.5, 104.0, + 101.0, 98.0, 95.0, 91.5, 88.0, 84.5, + 80.5, 77.0, 73.5, 69.5, 66.0, 62.5, + 58.5, 55.5, 52.0, 48.5, 45.5, 42.5, + 39.5, 36.5, 34.0, 31.5, 29.0, 26.5, + 24.5, 22.5, 20.5, 19.0, 17.5, 15.5, + 14.5, 13.0, 12.0, 10.5, 9.5, 8.5, + 8.0, 7.0, 6.5, 5.5, 5.0, 4.5, + 4.0, 3.5, 3.5, 3.0, 2.5, 2.5, + 2.0, 2.0, 1.5, 1.5, 1.0, 1.0, + 1.0, 1.0, 0.5, 0.5, 0.5, 0.5, + 0.5, 0.5 +}; + +// Quantizer lookup, step 1: bitrate classes +static const uint8_t PLM_AUDIO_QUANT_LUT_STEP_1[2][16] = { + // 32, 48, 56, 64, 80, 96,112,128,160,192,224,256,320,384 <- bitrate + { 0, 0, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2 }, // mono + // 16, 24, 28, 32, 40, 48, 56, 64, 80, 96,112,128,160,192 <- bitrate / chan + { 0, 0, 0, 0, 0, 0, 1, 1, 1, 2, 2, 2, 2, 2 } // stereo +}; + +// Quantizer lookup, step 2: bitrate class, sample rate -> B2 table idx, sblimit +static const uint8_t PLM_AUDIO_QUANT_TAB_A = (27 | 64); // Table 3-B.2a: high-rate, sblimit = 27 +static const uint8_t PLM_AUDIO_QUANT_TAB_B = (30 | 64); // Table 3-B.2b: high-rate, sblimit = 30 +static const uint8_t PLM_AUDIO_QUANT_TAB_C = 8; // Table 3-B.2c: low-rate, sblimit = 8 +static const uint8_t PLM_AUDIO_QUANT_TAB_D = 12; // Table 3-B.2d: low-rate, sblimit = 12 + +static const uint8_t QUANT_LUT_STEP_2[3][3] = { + //44.1 kHz, 48 kHz, 32 kHz + { PLM_AUDIO_QUANT_TAB_C, PLM_AUDIO_QUANT_TAB_C, PLM_AUDIO_QUANT_TAB_D }, // 32 - 48 kbit/sec/ch + { PLM_AUDIO_QUANT_TAB_A, PLM_AUDIO_QUANT_TAB_A, PLM_AUDIO_QUANT_TAB_A }, // 56 - 80 kbit/sec/ch + { PLM_AUDIO_QUANT_TAB_B, PLM_AUDIO_QUANT_TAB_A, PLM_AUDIO_QUANT_TAB_B } // 96+ kbit/sec/ch +}; + +// Quantizer lookup, step 3: B2 table, subband -> nbal, row index +// (upper 4 bits: nbal, lower 4 bits: row index) +static const uint8_t PLM_AUDIO_QUANT_LUT_STEP_3[3][32] = { + // Low-rate table (3-B.2c and 3-B.2d) + { + 0x44,0x44, + 0x34,0x34,0x34,0x34,0x34,0x34,0x34,0x34,0x34,0x34 + }, + // High-rate table (3-B.2a and 3-B.2b) + { + 0x43,0x43,0x43, + 0x42,0x42,0x42,0x42,0x42,0x42,0x42,0x42, + 0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31,0x31, + 0x20,0x20,0x20,0x20,0x20,0x20,0x20 + }, + // MPEG-2 LSR table (B.2 in ISO 13818-3) + { + 0x45,0x45,0x45,0x45, + 0x34,0x34,0x34,0x34,0x34,0x34,0x34, + 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24, + 0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24,0x24 + } +}; + +// Quantizer lookup, step 4: table row, allocation[] value -> quant table index +static const uint8_t PLM_AUDIO_QUANT_LUT_STEP_4[6][16] = { + { 0, 1, 2, 17 }, + { 0, 1, 2, 3, 4, 5, 6, 17 }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17 }, + { 0, 1, 3, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 }, + { 0, 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17 }, + { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 } +}; + +typedef struct plm_quantizer_spec_t { + unsigned short levels; + unsigned char group; + unsigned char bits; +} plm_quantizer_spec_t; + +static const plm_quantizer_spec_t PLM_AUDIO_QUANT_TAB[] = { + { 3, 1, 5 }, // 1 + { 5, 1, 7 }, // 2 + { 7, 0, 3 }, // 3 + { 9, 1, 10 }, // 4 + { 15, 0, 4 }, // 5 + { 31, 0, 5 }, // 6 + { 63, 0, 6 }, // 7 + { 127, 0, 7 }, // 8 + { 255, 0, 8 }, // 9 + { 511, 0, 9 }, // 10 + { 1023, 0, 10 }, // 11 + { 2047, 0, 11 }, // 12 + { 4095, 0, 12 }, // 13 + { 8191, 0, 13 }, // 14 + { 16383, 0, 14 }, // 15 + { 32767, 0, 15 }, // 16 + { 65535, 0, 16 } // 17 +}; + +typedef struct plm_audio_t { + double time; + int samples_decoded; + int samplerate_index; + int bitrate_index; + int version; + int layer; + int mode; + int bound; + int v_pos; + int next_frame_data_size; + int has_header; + + plm_buffer_t *buffer; + int destroy_buffer_when_done; + + const plm_quantizer_spec_t *allocation[2][32]; + uint8_t scale_factor_info[2][32]; + int scale_factor[2][32][3]; + int sample[2][32][3]; + + plm_samples_t samples; + float D[1024]; + float V[2][1024]; + float U[32]; +} plm_audio_t; + +int plm_audio_find_frame_sync(plm_audio_t *self); +int plm_audio_decode_header(plm_audio_t *self); +void plm_audio_decode_frame(plm_audio_t *self); +const plm_quantizer_spec_t *plm_audio_read_allocation(plm_audio_t *self, int sb, int tab3); +void plm_audio_read_samples(plm_audio_t *self, int ch, int sb, int part); +void plm_audio_idct36(int s[32][3], int ss, float *d, int dp); + +plm_audio_t *plm_audio_create_with_buffer(plm_buffer_t *buffer, int destroy_when_done) { + plm_audio_t *self = (plm_audio_t *)malloc(sizeof(plm_audio_t)); + memset(self, 0, sizeof(plm_audio_t)); + + self->samples.count = PLM_AUDIO_SAMPLES_PER_FRAME; + self->buffer = buffer; + self->destroy_buffer_when_done = destroy_when_done; + self->samplerate_index = 3; // Indicates 0 + + memcpy(self->D, PLM_AUDIO_SYNTHESIS_WINDOW, 512 * sizeof(float)); + memcpy(self->D + 512, PLM_AUDIO_SYNTHESIS_WINDOW, 512 * sizeof(float)); + + // Attempt to decode first header + self->next_frame_data_size = plm_audio_decode_header(self); + + return self; +} + +void plm_audio_destroy(plm_audio_t *self) { + if (self->destroy_buffer_when_done) { + plm_buffer_destroy(self->buffer); + } + free(self); +} + +int plm_audio_has_header(plm_audio_t *self) { + if (self->has_header) { + return TRUE; + } + + self->next_frame_data_size = plm_audio_decode_header(self); + return self->has_header; +} + +int plm_audio_get_samplerate(plm_audio_t *self) { + return plm_audio_has_header(self) + ? PLM_AUDIO_SAMPLE_RATE[self->samplerate_index] + : 0; +} + +double plm_audio_get_time(plm_audio_t *self) { + return self->time; +} + +void plm_audio_set_time(plm_audio_t *self, double time) { + self->samples_decoded = time * + (double)PLM_AUDIO_SAMPLE_RATE[self->samplerate_index]; + self->time = time; +} + +void plm_audio_rewind(plm_audio_t *self) { + plm_buffer_rewind(self->buffer); + self->time = 0; + self->samples_decoded = 0; + self->next_frame_data_size = 0; +} + +int plm_audio_has_ended(plm_audio_t *self) { + return plm_buffer_has_ended(self->buffer); +} + +plm_samples_t *plm_audio_decode(plm_audio_t *self) { + // Do we have at least enough information to decode the frame header? + if (!self->next_frame_data_size) { + if (!plm_buffer_has(self->buffer, 48)) { + return NULL; + } + self->next_frame_data_size = plm_audio_decode_header(self); + } + + if ( + self->next_frame_data_size == 0 || + !plm_buffer_has(self->buffer, self->next_frame_data_size << 3) + ) { + return NULL; + } + + plm_audio_decode_frame(self); + self->next_frame_data_size = 0; + + self->samples.time = self->time; + + self->samples_decoded += PLM_AUDIO_SAMPLES_PER_FRAME; + self->time = (double)self->samples_decoded / + (double)PLM_AUDIO_SAMPLE_RATE[self->samplerate_index]; + + return &self->samples; +} + +int plm_audio_find_frame_sync(plm_audio_t *self) { + size_t i; + for (i = self->buffer->bit_index >> 3; i < self->buffer->length-1; i++) { + if ( + self->buffer->bytes[i] == 0xFF && + (self->buffer->bytes[i+1] & 0xFE) == 0xFC + ) { + self->buffer->bit_index = ((i+1) << 3) + 3; + return TRUE; + } + } + self->buffer->bit_index = (i + 1) << 3; + return FALSE; +} + +int plm_audio_decode_header(plm_audio_t *self) { + if (!plm_buffer_has(self->buffer, 48)) { + return 0; + } + + plm_buffer_skip_bytes(self->buffer, 0x00); + int sync = plm_buffer_read(self->buffer, 11); + + + // Attempt to resync if no syncword was found. This sucks balls. The MP2 + // stream contains a syncword just before every frame (11 bits set to 1). + // However, this syncword is not guaranteed to not occur elswhere in the + // stream. So, if we have to resync, we also have to check if the header + // (samplerate, bitrate) differs from the one we had before. This all + // may still lead to garbage data being decoded :/ + + if (sync != PLM_AUDIO_FRAME_SYNC && !plm_audio_find_frame_sync(self)) { + return 0; + } + + self->version = plm_buffer_read(self->buffer, 2); + self->layer = plm_buffer_read(self->buffer, 2); + int hasCRC = !plm_buffer_read(self->buffer, 1); + + if ( + self->version != PLM_AUDIO_MPEG_1 || + self->layer != PLM_AUDIO_LAYER_II + ) { + return 0; + } + + int bitrate_index = plm_buffer_read(self->buffer, 4) - 1; + if (bitrate_index > 13) { + return 0; + } + + int samplerate_index = plm_buffer_read(self->buffer, 2); + if (samplerate_index == 3) { + return 0; + } + + int padding = plm_buffer_read(self->buffer, 1); + plm_buffer_skip(self->buffer, 1); // f_private + int mode = plm_buffer_read(self->buffer, 2); + + // If we already have a header, make sure the samplerate, bitrate and mode + // are still the same, otherwise we might have missed sync. + if ( + self->has_header && ( + self->bitrate_index != bitrate_index || + self->samplerate_index != samplerate_index || + self->mode != mode + ) + ) { + return 0; + } + + self->bitrate_index = bitrate_index; + self->samplerate_index = samplerate_index; + self->mode = mode; + self->has_header = TRUE; + + // Parse the mode_extension, set up the stereo bound + if (mode == PLM_AUDIO_MODE_JOINT_STEREO) { + self->bound = (plm_buffer_read(self->buffer, 2) + 1) << 2; + } + else { + plm_buffer_skip(self->buffer, 2); + self->bound = (mode == PLM_AUDIO_MODE_MONO) ? 0 : 32; + } + + // Discard the last 4 bits of the header and the CRC value, if present + plm_buffer_skip(self->buffer, 4); // copyright(1), original(1), emphasis(2) + if (hasCRC) { + plm_buffer_skip(self->buffer, 16); + } + + // Compute frame size, check if we have enough data to decode the whole + // frame. + int bitrate = PLM_AUDIO_BIT_RATE[self->bitrate_index]; + int samplerate = PLM_AUDIO_SAMPLE_RATE[self->samplerate_index]; + int frame_size = (144000 * bitrate / samplerate) + padding; + return frame_size - (hasCRC ? 6 : 4); +} + +void plm_audio_decode_frame(plm_audio_t *self) { + // Prepare the quantizer table lookups + int tab3 = 0; + int sblimit = 0; + + int tab1 = (self->mode == PLM_AUDIO_MODE_MONO) ? 0 : 1; + int tab2 = PLM_AUDIO_QUANT_LUT_STEP_1[tab1][self->bitrate_index]; + tab3 = QUANT_LUT_STEP_2[tab2][self->samplerate_index]; + sblimit = tab3 & 63; + tab3 >>= 6; + + if (self->bound > sblimit) { + self->bound = sblimit; + } + + // Read the allocation information + for (int sb = 0; sb < self->bound; sb++) { + self->allocation[0][sb] = plm_audio_read_allocation(self, sb, tab3); + self->allocation[1][sb] = plm_audio_read_allocation(self, sb, tab3); + } + + for (int sb = self->bound; sb < sblimit; sb++) { + self->allocation[0][sb] = + self->allocation[1][sb] = + plm_audio_read_allocation(self, sb, tab3); + } + + // Read scale factor selector information + int channels = (self->mode == PLM_AUDIO_MODE_MONO) ? 1 : 2; + for (int sb = 0; sb < sblimit; sb++) { + for (int ch = 0; ch < channels; ch++) { + if (self->allocation[ch][sb]) { + self->scale_factor_info[ch][sb] = plm_buffer_read(self->buffer, 2); + } + } + if (self->mode == PLM_AUDIO_MODE_MONO) { + self->scale_factor_info[1][sb] = self->scale_factor_info[0][sb]; + } + } + + // Read scale factors + for (int sb = 0; sb < sblimit; sb++) { + for (int ch = 0; ch < channels; ch++) { + if (self->allocation[ch][sb]) { + int *sf = self->scale_factor[ch][sb]; + switch (self->scale_factor_info[ch][sb]) { + case 0: + sf[0] = plm_buffer_read(self->buffer, 6); + sf[1] = plm_buffer_read(self->buffer, 6); + sf[2] = plm_buffer_read(self->buffer, 6); + break; + case 1: + sf[0] = + sf[1] = plm_buffer_read(self->buffer, 6); + sf[2] = plm_buffer_read(self->buffer, 6); + break; + case 2: + sf[0] = + sf[1] = + sf[2] = plm_buffer_read(self->buffer, 6); + break; + case 3: + sf[0] = plm_buffer_read(self->buffer, 6); + sf[1] = + sf[2] = plm_buffer_read(self->buffer, 6); + break; + } + } + } + if (self->mode == PLM_AUDIO_MODE_MONO) { + self->scale_factor[1][sb][0] = self->scale_factor[0][sb][0]; + self->scale_factor[1][sb][1] = self->scale_factor[0][sb][1]; + self->scale_factor[1][sb][2] = self->scale_factor[0][sb][2]; + } + } + + // Coefficient input and reconstruction + int out_pos = 0; + for (int part = 0; part < 3; part++) { + for (int granule = 0; granule < 4; granule++) { + + // Read the samples + for (int sb = 0; sb < self->bound; sb++) { + plm_audio_read_samples(self, 0, sb, part); + plm_audio_read_samples(self, 1, sb, part); + } + for (int sb = self->bound; sb < sblimit; sb++) { + plm_audio_read_samples(self, 0, sb, part); + self->sample[1][sb][0] = self->sample[0][sb][0]; + self->sample[1][sb][1] = self->sample[0][sb][1]; + self->sample[1][sb][2] = self->sample[0][sb][2]; + } + for (int sb = sblimit; sb < 32; sb++) { + self->sample[0][sb][0] = 0; + self->sample[0][sb][1] = 0; + self->sample[0][sb][2] = 0; + self->sample[1][sb][0] = 0; + self->sample[1][sb][1] = 0; + self->sample[1][sb][2] = 0; + } + + // Synthesis loop + for (int p = 0; p < 3; p++) { + // Shifting step + self->v_pos = (self->v_pos - 64) & 1023; + + for (int ch = 0; ch < 2; ch++) { + plm_audio_idct36(self->sample[ch], p, self->V[ch], self->v_pos); + + // Build U, windowing, calculate output + memset(self->U, 0, sizeof(self->U)); + + int d_index = 512 - (self->v_pos >> 1); + int v_index = (self->v_pos % 128) >> 1; + while (v_index < 1024) { + for (int i = 0; i < 32; ++i) { + self->U[i] += self->D[d_index++] * self->V[ch][v_index++]; + } + + v_index += 128 - 32; + d_index += 64 - 32; + } + + d_index -= (512 - 32); + v_index = (128 - 32 + 1024) - v_index; + while (v_index < 1024) { + for (int i = 0; i < 32; ++i) { + self->U[i] += self->D[d_index++] * self->V[ch][v_index++]; + } + + v_index += 128 - 32; + d_index += 64 - 32; + } + + // Output samples + #ifdef PLM_AUDIO_SEPARATE_CHANNELS + float *out_channel = ch == 0 + ? self->samples.left + : self->samples.right; + for (int j = 0; j < 32; j++) { + out_channel[out_pos + j] = self->U[j] / 2147418112.0f; + } + #else + for (int j = 0; j < 32; j++) { + self->samples.interleaved[((out_pos + j) << 1) + ch] = + self->U[j] / 2147418112.0f; + } + #endif + } // End of synthesis channel loop + out_pos += 32; + } // End of synthesis sub-block loop + + } // Decoding of the granule finished + } + + plm_buffer_align(self->buffer); +} + +const plm_quantizer_spec_t *plm_audio_read_allocation(plm_audio_t *self, int sb, int tab3) { + int tab4 = PLM_AUDIO_QUANT_LUT_STEP_3[tab3][sb]; + int qtab = PLM_AUDIO_QUANT_LUT_STEP_4[tab4 & 15][plm_buffer_read(self->buffer, tab4 >> 4)]; + return qtab ? (&PLM_AUDIO_QUANT_TAB[qtab - 1]) : 0; +} + +void plm_audio_read_samples(plm_audio_t *self, int ch, int sb, int part) { + const plm_quantizer_spec_t *q = self->allocation[ch][sb]; + int sf = self->scale_factor[ch][sb][part]; + int *sample = self->sample[ch][sb]; + int val = 0; + + if (!q) { + // No bits allocated for this subband + sample[0] = sample[1] = sample[2] = 0; + return; + } + + // Resolve scalefactor + if (sf == 63) { + sf = 0; + } + else { + int shift = (sf / 3) | 0; + sf = (PLM_AUDIO_SCALEFACTOR_BASE[sf % 3] + ((1 << shift) >> 1)) >> shift; + } + + // Decode samples + int adj = q->levels; + if (q->group) { + // Decode grouped samples + val = plm_buffer_read(self->buffer, q->bits); + sample[0] = val % adj; + val /= adj; + sample[1] = val % adj; + sample[2] = val / adj; + } + else { + // Decode direct samples + sample[0] = plm_buffer_read(self->buffer, q->bits); + sample[1] = plm_buffer_read(self->buffer, q->bits); + sample[2] = plm_buffer_read(self->buffer, q->bits); + } + + // Postmultiply samples + int scale = 65536 / (adj + 1); + adj = ((adj + 1) >> 1) - 1; + + val = (adj - sample[0]) * scale; + sample[0] = (val * (sf >> 12) + ((val * (sf & 4095) + 2048) >> 12)) >> 12; + + val = (adj - sample[1]) * scale; + sample[1] = (val * (sf >> 12) + ((val * (sf & 4095) + 2048) >> 12)) >> 12; + + val = (adj - sample[2]) * scale; + sample[2] = (val * (sf >> 12) + ((val * (sf & 4095) + 2048) >> 12)) >> 12; +} + +void plm_audio_idct36(int s[32][3], int ss, float *d, int dp) { + float t01, t02, t03, t04, t05, t06, t07, t08, t09, t10, t11, t12, + t13, t14, t15, t16, t17, t18, t19, t20, t21, t22, t23, t24, + t25, t26, t27, t28, t29, t30, t31, t32, t33; + + t01 = (float)(s[0][ss] + s[31][ss]); t02 = (float)(s[0][ss] - s[31][ss]) * 0.500602998235f; + t03 = (float)(s[1][ss] + s[30][ss]); t04 = (float)(s[1][ss] - s[30][ss]) * 0.505470959898f; + t05 = (float)(s[2][ss] + s[29][ss]); t06 = (float)(s[2][ss] - s[29][ss]) * 0.515447309923f; + t07 = (float)(s[3][ss] + s[28][ss]); t08 = (float)(s[3][ss] - s[28][ss]) * 0.53104259109f; + t09 = (float)(s[4][ss] + s[27][ss]); t10 = (float)(s[4][ss] - s[27][ss]) * 0.553103896034f; + t11 = (float)(s[5][ss] + s[26][ss]); t12 = (float)(s[5][ss] - s[26][ss]) * 0.582934968206f; + t13 = (float)(s[6][ss] + s[25][ss]); t14 = (float)(s[6][ss] - s[25][ss]) * 0.622504123036f; + t15 = (float)(s[7][ss] + s[24][ss]); t16 = (float)(s[7][ss] - s[24][ss]) * 0.674808341455f; + t17 = (float)(s[8][ss] + s[23][ss]); t18 = (float)(s[8][ss] - s[23][ss]) * 0.744536271002f; + t19 = (float)(s[9][ss] + s[22][ss]); t20 = (float)(s[9][ss] - s[22][ss]) * 0.839349645416f; + t21 = (float)(s[10][ss] + s[21][ss]); t22 = (float)(s[10][ss] - s[21][ss]) * 0.972568237862f; + t23 = (float)(s[11][ss] + s[20][ss]); t24 = (float)(s[11][ss] - s[20][ss]) * 1.16943993343f; + t25 = (float)(s[12][ss] + s[19][ss]); t26 = (float)(s[12][ss] - s[19][ss]) * 1.48416461631f; + t27 = (float)(s[13][ss] + s[18][ss]); t28 = (float)(s[13][ss] - s[18][ss]) * 2.05778100995f; + t29 = (float)(s[14][ss] + s[17][ss]); t30 = (float)(s[14][ss] - s[17][ss]) * 3.40760841847f; + t31 = (float)(s[15][ss] + s[16][ss]); t32 = (float)(s[15][ss] - s[16][ss]) * 10.1900081235f; + + t33 = t01 + t31; t31 = (t01 - t31) * 0.502419286188f; + t01 = t03 + t29; t29 = (t03 - t29) * 0.52249861494f; + t03 = t05 + t27; t27 = (t05 - t27) * 0.566944034816f; + t05 = t07 + t25; t25 = (t07 - t25) * 0.64682178336f; + t07 = t09 + t23; t23 = (t09 - t23) * 0.788154623451f; + t09 = t11 + t21; t21 = (t11 - t21) * 1.06067768599f; + t11 = t13 + t19; t19 = (t13 - t19) * 1.72244709824f; + t13 = t15 + t17; t17 = (t15 - t17) * 5.10114861869f; + t15 = t33 + t13; t13 = (t33 - t13) * 0.509795579104f; + t33 = t01 + t11; t01 = (t01 - t11) * 0.601344886935f; + t11 = t03 + t09; t09 = (t03 - t09) * 0.899976223136f; + t03 = t05 + t07; t07 = (t05 - t07) * 2.56291544774f; + t05 = t15 + t03; t15 = (t15 - t03) * 0.541196100146f; + t03 = t33 + t11; t11 = (t33 - t11) * 1.30656296488f; + t33 = t05 + t03; t05 = (t05 - t03) * 0.707106781187f; + t03 = t15 + t11; t15 = (t15 - t11) * 0.707106781187f; + t03 += t15; + t11 = t13 + t07; t13 = (t13 - t07) * 0.541196100146f; + t07 = t01 + t09; t09 = (t01 - t09) * 1.30656296488f; + t01 = t11 + t07; t07 = (t11 - t07) * 0.707106781187f; + t11 = t13 + t09; t13 = (t13 - t09) * 0.707106781187f; + t11 += t13; t01 += t11; + t11 += t07; t07 += t13; + t09 = t31 + t17; t31 = (t31 - t17) * 0.509795579104f; + t17 = t29 + t19; t29 = (t29 - t19) * 0.601344886935f; + t19 = t27 + t21; t21 = (t27 - t21) * 0.899976223136f; + t27 = t25 + t23; t23 = (t25 - t23) * 2.56291544774f; + t25 = t09 + t27; t09 = (t09 - t27) * 0.541196100146f; + t27 = t17 + t19; t19 = (t17 - t19) * 1.30656296488f; + t17 = t25 + t27; t27 = (t25 - t27) * 0.707106781187f; + t25 = t09 + t19; t19 = (t09 - t19) * 0.707106781187f; + t25 += t19; + t09 = t31 + t23; t31 = (t31 - t23) * 0.541196100146f; + t23 = t29 + t21; t21 = (t29 - t21) * 1.30656296488f; + t29 = t09 + t23; t23 = (t09 - t23) * 0.707106781187f; + t09 = t31 + t21; t31 = (t31 - t21) * 0.707106781187f; + t09 += t31; t29 += t09; t09 += t23; t23 += t31; + t17 += t29; t29 += t25; t25 += t09; t09 += t27; + t27 += t23; t23 += t19; t19 += t31; + t21 = t02 + t32; t02 = (t02 - t32) * 0.502419286188f; + t32 = t04 + t30; t04 = (t04 - t30) * 0.52249861494f; + t30 = t06 + t28; t28 = (t06 - t28) * 0.566944034816f; + t06 = t08 + t26; t08 = (t08 - t26) * 0.64682178336f; + t26 = t10 + t24; t10 = (t10 - t24) * 0.788154623451f; + t24 = t12 + t22; t22 = (t12 - t22) * 1.06067768599f; + t12 = t14 + t20; t20 = (t14 - t20) * 1.72244709824f; + t14 = t16 + t18; t16 = (t16 - t18) * 5.10114861869f; + t18 = t21 + t14; t14 = (t21 - t14) * 0.509795579104f; + t21 = t32 + t12; t32 = (t32 - t12) * 0.601344886935f; + t12 = t30 + t24; t24 = (t30 - t24) * 0.899976223136f; + t30 = t06 + t26; t26 = (t06 - t26) * 2.56291544774f; + t06 = t18 + t30; t18 = (t18 - t30) * 0.541196100146f; + t30 = t21 + t12; t12 = (t21 - t12) * 1.30656296488f; + t21 = t06 + t30; t30 = (t06 - t30) * 0.707106781187f; + t06 = t18 + t12; t12 = (t18 - t12) * 0.707106781187f; + t06 += t12; + t18 = t14 + t26; t26 = (t14 - t26) * 0.541196100146f; + t14 = t32 + t24; t24 = (t32 - t24) * 1.30656296488f; + t32 = t18 + t14; t14 = (t18 - t14) * 0.707106781187f; + t18 = t26 + t24; t24 = (t26 - t24) * 0.707106781187f; + t18 += t24; t32 += t18; + t18 += t14; t26 = t14 + t24; + t14 = t02 + t16; t02 = (t02 - t16) * 0.509795579104f; + t16 = t04 + t20; t04 = (t04 - t20) * 0.601344886935f; + t20 = t28 + t22; t22 = (t28 - t22) * 0.899976223136f; + t28 = t08 + t10; t10 = (t08 - t10) * 2.56291544774f; + t08 = t14 + t28; t14 = (t14 - t28) * 0.541196100146f; + t28 = t16 + t20; t20 = (t16 - t20) * 1.30656296488f; + t16 = t08 + t28; t28 = (t08 - t28) * 0.707106781187f; + t08 = t14 + t20; t20 = (t14 - t20) * 0.707106781187f; + t08 += t20; + t14 = t02 + t10; t02 = (t02 - t10) * 0.541196100146f; + t10 = t04 + t22; t22 = (t04 - t22) * 1.30656296488f; + t04 = t14 + t10; t10 = (t14 - t10) * 0.707106781187f; + t14 = t02 + t22; t02 = (t02 - t22) * 0.707106781187f; + t14 += t02; t04 += t14; t14 += t10; t10 += t02; + t16 += t04; t04 += t08; t08 += t14; t14 += t28; + t28 += t10; t10 += t20; t20 += t02; t21 += t16; + t16 += t32; t32 += t04; t04 += t06; t06 += t08; + t08 += t18; t18 += t14; t14 += t30; t30 += t28; + t28 += t26; t26 += t10; t10 += t12; t12 += t20; + t20 += t24; t24 += t02; + + d[dp + 48] = -t33; + d[dp + 49] = d[dp + 47] = -t21; + d[dp + 50] = d[dp + 46] = -t17; + d[dp + 51] = d[dp + 45] = -t16; + d[dp + 52] = d[dp + 44] = -t01; + d[dp + 53] = d[dp + 43] = -t32; + d[dp + 54] = d[dp + 42] = -t29; + d[dp + 55] = d[dp + 41] = -t04; + d[dp + 56] = d[dp + 40] = -t03; + d[dp + 57] = d[dp + 39] = -t06; + d[dp + 58] = d[dp + 38] = -t25; + d[dp + 59] = d[dp + 37] = -t08; + d[dp + 60] = d[dp + 36] = -t11; + d[dp + 61] = d[dp + 35] = -t18; + d[dp + 62] = d[dp + 34] = -t09; + d[dp + 63] = d[dp + 33] = -t14; + d[dp + 32] = -t05; + d[dp + 0] = t05; d[dp + 31] = -t30; + d[dp + 1] = t30; d[dp + 30] = -t27; + d[dp + 2] = t27; d[dp + 29] = -t28; + d[dp + 3] = t28; d[dp + 28] = -t07; + d[dp + 4] = t07; d[dp + 27] = -t26; + d[dp + 5] = t26; d[dp + 26] = -t23; + d[dp + 6] = t23; d[dp + 25] = -t10; + d[dp + 7] = t10; d[dp + 24] = -t15; + d[dp + 8] = t15; d[dp + 23] = -t12; + d[dp + 9] = t12; d[dp + 22] = -t19; + d[dp + 10] = t19; d[dp + 21] = -t20; + d[dp + 11] = t20; d[dp + 20] = -t13; + d[dp + 12] = t13; d[dp + 19] = -t24; + d[dp + 13] = t24; d[dp + 18] = -t31; + d[dp + 14] = t31; d[dp + 17] = -t02; + d[dp + 15] = t02; d[dp + 16] = 0.0; +} + + +#endif // PL_MPEG_IMPLEMENTATION |