mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-18 03:19:31 +02:00
ba87f0801d
Passing an explicit filename to this command is only necessary if the documentation in the @file block refers to a file different from the one the block resides in. Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk
95 lines
3.5 KiB
C
95 lines
3.5 KiB
C
/*
|
|
* MJPEG A dump header bitstream filter
|
|
* Copyright (c) 2006 Baptiste Coudurier
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* MJPEG A dump header bitstream filter
|
|
* modifies bitstream to be decoded by quicktime
|
|
*/
|
|
|
|
#include "avcodec.h"
|
|
#include "bytestream.h"
|
|
#include "mjpeg.h"
|
|
|
|
|
|
static int mjpega_dump_header(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
|
|
uint8_t **poutbuf, int *poutbuf_size,
|
|
const uint8_t *buf, int buf_size, int keyframe)
|
|
{
|
|
uint8_t *poutbufp;
|
|
unsigned dqt = 0, dht = 0, sof0 = 0;
|
|
int i;
|
|
|
|
if (avctx->codec_id != CODEC_ID_MJPEG) {
|
|
av_log(avctx, AV_LOG_ERROR, "mjpega bitstream filter only applies to mjpeg codec\n");
|
|
return 0;
|
|
}
|
|
|
|
*poutbuf_size = 0;
|
|
*poutbuf = av_malloc(buf_size + 44 + FF_INPUT_BUFFER_PADDING_SIZE);
|
|
poutbufp = *poutbuf;
|
|
bytestream_put_byte(&poutbufp, 0xff);
|
|
bytestream_put_byte(&poutbufp, SOI);
|
|
bytestream_put_byte(&poutbufp, 0xff);
|
|
bytestream_put_byte(&poutbufp, APP1);
|
|
bytestream_put_be16(&poutbufp, 42); /* size */
|
|
bytestream_put_be32(&poutbufp, 0);
|
|
bytestream_put_buffer(&poutbufp, "mjpg", 4);
|
|
bytestream_put_be32(&poutbufp, buf_size + 44); /* field size */
|
|
bytestream_put_be32(&poutbufp, buf_size + 44); /* pad field size */
|
|
bytestream_put_be32(&poutbufp, 0); /* next ptr */
|
|
|
|
for (i = 0; i < buf_size - 1; i++) {
|
|
if (buf[i] == 0xff) {
|
|
switch (buf[i + 1]) {
|
|
case DQT: dqt = i + 46; break;
|
|
case DHT: dht = i + 46; break;
|
|
case SOF0: sof0 = i + 46; break;
|
|
case SOS:
|
|
bytestream_put_be32(&poutbufp, dqt); /* quant off */
|
|
bytestream_put_be32(&poutbufp, dht); /* huff off */
|
|
bytestream_put_be32(&poutbufp, sof0); /* image off */
|
|
bytestream_put_be32(&poutbufp, i + 46); /* scan off */
|
|
bytestream_put_be32(&poutbufp, i + 46 + AV_RB16(buf + i + 2)); /* data off */
|
|
bytestream_put_buffer(&poutbufp, buf + 2, buf_size - 2); /* skip already written SOI */
|
|
*poutbuf_size = poutbufp - *poutbuf;
|
|
return 1;
|
|
case APP1:
|
|
if (i + 8 < buf_size && AV_RL32(buf + i + 8) == AV_RL32("mjpg")) {
|
|
av_log(avctx, AV_LOG_ERROR, "bitstream already formatted\n");
|
|
memcpy(*poutbuf, buf, buf_size);
|
|
*poutbuf_size = buf_size;
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
av_freep(poutbuf);
|
|
av_log(avctx, AV_LOG_ERROR, "could not find SOS marker in bitstream\n");
|
|
return 0;
|
|
}
|
|
|
|
AVBitStreamFilter mjpega_dump_header_bsf = {
|
|
"mjpegadump",
|
|
0,
|
|
mjpega_dump_header,
|
|
};
|