diff options
author | Nicolas George <nicolas.george@normalesup.org> | 2010-11-11 18:24:11 +0300 |
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committer | Nicolas George <nicolas.george@normalesup.org> | 2010-11-11 18:24:11 +0300 |
commit | ba83c4bfb55d5c3fc6b3959edb0d3cda07a70241 (patch) | |
tree | 6fc4a3763a476c355f9efd4cf0713b65a2c4368a | |
parent | 2c5168afed8ddd798dae5909dba85ae3b611f894 (diff) |
MJPEG/AVI1 to JPEG/JFIF bitstream filter.
Originally committed as revision 25721 to svn://svn.ffmpeg.org/ffmpeg/trunk
-rw-r--r-- | Changelog | 1 | ||||
-rw-r--r-- | doc/bitstream_filters.texi | 37 | ||||
-rw-r--r-- | doc/ffmpeg-doc.texi | 2 | ||||
-rw-r--r-- | libavcodec/Makefile | 1 | ||||
-rw-r--r-- | libavcodec/allcodecs.c | 1 | ||||
-rw-r--r-- | libavcodec/mjpeg2jpeg_bsf.c | 113 |
6 files changed, 154 insertions, 1 deletions
@@ -53,6 +53,7 @@ version <next>: - single stream LATM/LOAS decoder - setpts filter added - Win64 support for optimized asm functions +- MJPEG/AVI1 to JPEG/JFIF bitstream filter version 0.6: diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi index 0bcb6c7f60..1ad67cd5ef 100644 --- a/doc/bitstream_filters.texi +++ b/doc/bitstream_filters.texi @@ -25,6 +25,43 @@ Below is a description of the currently available bitstream filters. @section imx_dump_header +@section mjpeg2jpeg + +Convert MJPEG/AVI1 packets to full JPEG/JFIF packets. + +MJPEG is a video codec wherein each video frame is essentially a +JPEG image. The individual frames can be extracted without loss, +e.g. by + +@example +ffmpeg -i ../some_mjpeg.avi -vcodec copy frames_%d.jpg +@end example + +Unfortunately, these chunks are incomplete JPEG images, because +they lack the DHT segment required for decoding. Quoting from +@url{http://www.digitalpreservation.gov/formats/fdd/fdd000063.shtml}: + +Avery Lee, writing in the rec.video.desktop newsgroup in 2001, +commented that "MJPEG, or at least the MJPEG in AVIs having the +MJPG fourcc, is restricted JPEG with a fixed -- and *omitted* -- +Huffman table. The JPEG must be YCbCr colorspace, it must be 4:2:2, +and it must use basic Huffman encoding, not arithmetic or +progressive. . . . You can indeed extract the MJPEG frames and +decode them with a regular JPEG decoder, but you have to prepend +the DHT segment to them, or else the decoder won't have any idea +how to decompress the data. The exact table necessary is given in +the OpenDML spec." + +This bitstream filter patches the header of frames extracted from an MJPEG +stream (carrying the AVI1 header ID and lacking a DHT segment) to +produce fully qualified JPEG images. + +@example +ffmpeg -i mjpeg-movie.avi -vcodec copy -vbsf mjpeg2jpeg frame_%d.jpg +exiftran -i -9 frame*.jpg +ffmpeg -i frame_%d.jpg -vcodec copy rotated.avi +@end example + @section mjpega_dump_header @section movsub diff --git a/doc/ffmpeg-doc.texi b/doc/ffmpeg-doc.texi index b33ea5e7b4..e2e0df7f2f 100644 --- a/doc/ffmpeg-doc.texi +++ b/doc/ffmpeg-doc.texi @@ -522,7 +522,7 @@ Force video tag/fourcc. @item -qphist Show QP histogram. @item -vbsf @var{bitstream_filter} -Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump". +Bitstream filters available are "dump_extra", "remove_extra", "noise", "h264_mp4toannexb", "imxdump", "mjpegadump", "mjpeg2jpeg". @example ffmpeg -i h264.mp4 -vcodec copy -vbsf h264_mp4toannexb -an out.h264 @end example diff --git a/libavcodec/Makefile b/libavcodec/Makefile index 5abc4954f4..04fe93542b 100644 --- a/libavcodec/Makefile +++ b/libavcodec/Makefile @@ -602,6 +602,7 @@ OBJS-$(CONFIG_CHOMP_BSF) += chomp_bsf.o OBJS-$(CONFIG_DUMP_EXTRADATA_BSF) += dump_extradata_bsf.o OBJS-$(CONFIG_H264_MP4TOANNEXB_BSF) += h264_mp4toannexb_bsf.o OBJS-$(CONFIG_IMX_DUMP_HEADER_BSF) += imx_dump_header_bsf.o +OBJS-$(CONFIG_MJPEG2JPEG_BSF) += mjpeg2jpeg_bsf.o OBJS-$(CONFIG_MJPEGA_DUMP_HEADER_BSF) += mjpega_dump_header_bsf.o OBJS-$(CONFIG_MOV2TEXTSUB_BSF) += movsub_bsf.o OBJS-$(CONFIG_MP3_HEADER_COMPRESS_BSF) += mp3_header_compress_bsf.o diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c index c3e4647c8c..66b858d93a 100644 --- a/libavcodec/allcodecs.c +++ b/libavcodec/allcodecs.c @@ -394,6 +394,7 @@ void avcodec_register_all(void) REGISTER_BSF (DUMP_EXTRADATA, dump_extradata); REGISTER_BSF (H264_MP4TOANNEXB, h264_mp4toannexb); REGISTER_BSF (IMX_DUMP_HEADER, imx_dump_header); + REGISTER_BSF (MJPEG2JPEG, mjpeg2jpeg); REGISTER_BSF (MJPEGA_DUMP_HEADER, mjpega_dump_header); REGISTER_BSF (MP3_HEADER_COMPRESS, mp3_header_compress); REGISTER_BSF (MP3_HEADER_DECOMPRESS, mp3_header_decompress); diff --git a/libavcodec/mjpeg2jpeg_bsf.c b/libavcodec/mjpeg2jpeg_bsf.c new file mode 100644 index 0000000000..36bb749c5a --- /dev/null +++ b/libavcodec/mjpeg2jpeg_bsf.c @@ -0,0 +1,113 @@ +/* + * MJPEG/AVI1 to JPEG/JFIF bitstream format filter + * Copyright (c) 2010 Adrian Daerr and Nicolas George + * + * This file is part of FFmpeg. + * + * FFmpeg 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 2.1 of the License, or (at your option) any later version. + * + * FFmpeg 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 FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +/* + * Adapted from mjpeg2jpeg.c, with original copyright: + * Paris 2010 Adrian Daerr, public domain + */ + +#include <string.h> +#include "avcodec.h" +#include "mjpeg.h" + +static const uint8_t jpeg_header[] = { + 0xff, 0xd8, // SOI + 0xff, 0xe0, // APP0 + 0x00, 0x10, // APP0 header size (including + // this field, but excluding preceding) + 0x4a, 0x46, 0x49, 0x46, 0x00, // ID string 'JFIF\0' + 0x01, 0x01, // version + 0x00, // bits per type + 0x00, 0x00, // X density + 0x00, 0x00, // Y density + 0x00, // X thumbnail size + 0x00, // Y thumbnail size +}; + +static const int dht_segment_size = 420; +static const uint8_t dht_segment_head[] = { 0xFF, 0xC4, 0x01, 0xA2, 0x00 }; +static const uint8_t dht_segment_frag[] = { + 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, + 0x0a, 0x0b, 0x01, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, + 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, +}; + +static uint8_t *append(uint8_t *buf, const uint8_t *src, int size) +{ + memcpy(buf, src, size); + return buf + size; +} + +static uint8_t *append_dht_segment(uint8_t *buf) +{ + buf = append(buf, dht_segment_head, sizeof(dht_segment_head)); + buf = append(buf, ff_mjpeg_bits_dc_luminance + 1, 16); + buf = append(buf, dht_segment_frag, sizeof(dht_segment_frag)); + buf = append(buf, ff_mjpeg_val_dc, 12); + *(buf++) = 0x10; + buf = append(buf, ff_mjpeg_bits_ac_luminance + 1, 16); + buf = append(buf, ff_mjpeg_val_ac_luminance, 162); + *(buf++) = 0x11; + buf = append(buf, ff_mjpeg_bits_ac_chrominance + 1, 16); + buf = append(buf, ff_mjpeg_val_ac_chrominance, 162); + return buf; +} + +static int mjpeg2jpeg_filter(AVBitStreamFilterContext *bsfc, + AVCodecContext *avctx, const char *args, + uint8_t **poutbuf, int *poutbuf_size, + const uint8_t *buf, int buf_size, + int keyframe) +{ + int input_skip, output_size; + uint8_t *output, *out; + + if (buf_size < 12) { + av_log(avctx, AV_LOG_ERROR, "input is truncated\n"); + return AVERROR_INVALIDDATA; + } + if (memcmp("AVI1", buf + 6, 4)) { + av_log(avctx, AV_LOG_ERROR, "input is not MJPEG/AVI1\n"); + return AVERROR_INVALIDDATA; + } + input_skip = (buf[4] << 8) + buf[5] + 4; + if (buf_size < input_skip) { + av_log(avctx, AV_LOG_ERROR, "input is truncated\n"); + return AVERROR_INVALIDDATA; + } + output_size = buf_size - input_skip + + sizeof(jpeg_header) + dht_segment_size; + output = out = av_malloc(output_size); + if (!output) + return AVERROR(ENOMEM); + out = append(out, jpeg_header, sizeof(jpeg_header)); + out = append_dht_segment(out); + out = append(out, buf + input_skip, buf_size - input_skip); + *poutbuf = output; + *poutbuf_size = output_size; + return 1; +} + +AVBitStreamFilter mjpeg2jpeg_bsf = { + .name = "mjpeg2jpeg", + .priv_data_size = 0, + .filter = mjpeg2jpeg_filter, +}; |