diff options
author | Mike Melanson <mike@multimedia.cx> | 2003-10-01 08:39:38 +0400 |
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committer | Mike Melanson <mike@multimedia.cx> | 2003-10-01 08:39:38 +0400 |
commit | 2fdf638b0c66c22357d56f7cb205dd241b4a8c58 (patch) | |
tree | cdf625b0779d58f7a4c439ac61d6ba193911a81d /libavcodec/msrle.c | |
parent | f2f6134b9e5abb0890867d47ba8c0e293d0ba2fe (diff) |
New demuxers: Sega FILM/CPK, Westwood VQA & AUD; new decoders: MS RLE &
Video-1, Apple RPZA, Cinepak, Westwood IMA ADPCM
Originally committed as revision 2324 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/msrle.c')
-rw-r--r-- | libavcodec/msrle.c | 219 |
1 files changed, 219 insertions, 0 deletions
diff --git a/libavcodec/msrle.c b/libavcodec/msrle.c new file mode 100644 index 0000000000..8943ef3cdf --- /dev/null +++ b/libavcodec/msrle.c @@ -0,0 +1,219 @@ +/* + * Micrsoft RLE Video Decoder + * Copyright (C) 2003 the ffmpeg project + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/** + * @file msrle.c + * MS RLE Video Decoder by Mike Melanson (melanson@pcisys.net) + * For more information about the MS RLE format, visit: + * http://www.pcisys.net/~melanson/codecs/ + * + * The MS RLE decoder outputs PAL8 colorspace data. + * + * Note that this decoder expects the palette colors from the end of the + * BITMAPINFO header passed through extradata. + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "common.h" +#include "avcodec.h" +#include "dsputil.h" + +typedef struct MsrleContext { + AVCodecContext *avctx; + AVFrame frame; + AVFrame prev_frame; + + unsigned char *buf; + int size; + + unsigned int palette[256]; +} MsrleContext; + +#define FETCH_NEXT_STREAM_BYTE() \ + if (stream_ptr >= s->size) \ + { \ + printf(" MS RLE: stream ptr just went out of bounds (1)\n"); \ + return; \ + } \ + stream_byte = s->buf[stream_ptr++]; + +static void msrle_decode_pal8(MsrleContext *s) +{ + int stream_ptr = 0; + unsigned char rle_code; + unsigned char extra_byte; + unsigned char stream_byte; + int pixel_ptr = 0; + int row_dec = s->frame.linesize[0]; + int row_ptr = (s->avctx->height - 1) * row_dec; + int frame_size = row_dec * s->avctx->height; + + while (row_ptr >= 0) { + FETCH_NEXT_STREAM_BYTE(); + rle_code = stream_byte; + if (rle_code == 0) { + /* fetch the next byte to see how to handle escape code */ + FETCH_NEXT_STREAM_BYTE(); + if (stream_byte == 0) { + /* line is done, goto the next one */ + row_ptr -= row_dec; + pixel_ptr = 0; + } else if (stream_byte == 1) { + /* decode is done */ + return; + } else if (stream_byte == 2) { + /* reposition frame decode coordinates */ + FETCH_NEXT_STREAM_BYTE(); + pixel_ptr += stream_byte; + FETCH_NEXT_STREAM_BYTE(); + row_ptr -= stream_byte * row_dec; + } else { + /* copy pixels from encoded stream */ + if ((row_ptr + pixel_ptr + stream_byte > frame_size) || + (row_ptr < 0)) { + printf(" MS RLE: frame ptr just went out of bounds (1)\n"); + return; + } + + rle_code = stream_byte; + extra_byte = stream_byte & 0x01; + if (stream_ptr + rle_code + extra_byte > s->size) { + printf(" MS RLE: stream ptr just went out of bounds (2)\n"); + return; + } + + while (rle_code--) { + FETCH_NEXT_STREAM_BYTE(); + s->frame.data[0][row_ptr + pixel_ptr] = stream_byte; + pixel_ptr++; + } + + /* if the RLE code is odd, skip a byte in the stream */ + if (extra_byte) + stream_ptr++; + } + } else { + /* decode a run of data */ + if ((row_ptr + pixel_ptr + stream_byte > frame_size) || + (row_ptr < 0)) { + printf(" MS RLE: frame ptr just went out of bounds (2)\n"); + return; + } + + FETCH_NEXT_STREAM_BYTE(); + + while(rle_code--) { + s->frame.data[0][row_ptr + pixel_ptr] = stream_byte; + pixel_ptr++; + } + } + } + + /* make the palette available */ + memcpy(s->frame.data[1], s->palette, 256 * 4); + + /* one last sanity check on the way out */ + if (stream_ptr < s->size) + printf(" MS RLE: ended frame decode with bytes left over (%d < %d)\n", + stream_ptr, s->size); +} + +static int msrle_decode_init(AVCodecContext *avctx) +{ + MsrleContext *s = (MsrleContext *)avctx->priv_data; + int i, j; + unsigned char *palette; + + s->avctx = avctx; + + avctx->pix_fmt = PIX_FMT_PAL8; + avctx->has_b_frames = 0; + s->frame.data[0] = s->prev_frame.data[0] = NULL; + + /* convert palette */ + palette = (unsigned char *)s->avctx->extradata; + memset (s->palette, 0, 256 * 4); + for (i = 0, j = 0; i < s->avctx->extradata_size / 4; i++, j += 4) + s->palette[i] = + (palette[j + 2] << 16) | + (palette[j + 1] << 8) | + (palette[j + 0] << 0); + + return 0; +} + +static int msrle_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf, int buf_size) +{ + MsrleContext *s = (MsrleContext *)avctx->priv_data; + + s->buf = buf; + s->size = buf_size; + + if (avctx->get_buffer(avctx, &s->frame)) { + printf (" MS RLE: get_buffer() failed\n"); + return -1; + } + + /* grossly inefficient, but...oh well */ + memcpy(s->frame.data[0], s->prev_frame.data[0], + s->frame.linesize[0] * s->avctx->height); + + msrle_decode_pal8(s); + + if (s->frame.data[0]) + avctx->release_buffer(avctx, &s->frame); + + /* shuffle frames */ + s->prev_frame = s->frame; + + *data_size = sizeof(AVFrame); + *(AVFrame*)data = s->frame; + + /* report that the buffer was completely consumed */ + return buf_size; +} + +static int msrle_decode_end(AVCodecContext *avctx) +{ + MsrleContext *s = (MsrleContext *)avctx->priv_data; + + /* release the last frame */ + if (s->prev_frame.data[0]) + avctx->release_buffer(avctx, &s->prev_frame); + + return 0; +} + +AVCodec msrle_decoder = { + "msrle", + CODEC_TYPE_VIDEO, + CODEC_ID_MSRLE, + sizeof(MsrleContext), + msrle_decode_init, + NULL, + msrle_decode_end, + msrle_decode_frame, + CODEC_CAP_DR1, +}; 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