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lavc: remove mp3_header_(de)compress bitstream filters

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They mangle the mp3 header in a non-standard way to save a few bytes.
People who care about space so much should just use a more efficient
codec.
This commit is contained in:
Anton Khirnov
2013-11-24 14:14:13 +01:00
parent 1eaac1d6f7
commit c6080d8900
5 changed files with 1 additions and 191 deletions
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1
Changelog
View File

@@ -49,6 +49,7 @@ version 10:
- dar variable in the scale filter now returns the actual DAR (i.e. a * sar)
- VP9 decoder
- support for decoding through VDPAU in avconv (the -hwaccel option)
- remove mp3_header_(de)compress bitstream filters
version 9:

3
libavcodec/Makefile
View File

@@ -672,9 +672,6 @@ OBJS-$(CONFIG_IMX_DUMP_HEADER_BSF) += imx_dump_header_bsf.o
OBJS-$(CONFIG_MJPEG2JPEG_BSF) += mjpeg2jpeg_bsf.o mjpeg.o
OBJS-$(CONFIG_MJPEGA_DUMP_HEADER_BSF) += mjpega_dump_header_bsf.o
OBJS-$(CONFIG_MOV2TEXTSUB_BSF) += movsub_bsf.o
OBJS-$(CONFIG_MP3_HEADER_COMPRESS_BSF) += mp3_header_compress_bsf.o
OBJS-$(CONFIG_MP3_HEADER_DECOMPRESS_BSF) += mp3_header_decompress_bsf.o \
mpegaudiodata.o
OBJS-$(CONFIG_NOISE_BSF) += noise_bsf.o
OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF) += remove_extradata_bsf.o
OBJS-$(CONFIG_TEXT2MOVSUB_BSF) += movsub_bsf.o

2
libavcodec/allcodecs.c
View File

@@ -481,8 +481,6 @@ void avcodec_register_all(void)
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);
REGISTER_BSF(MOV2TEXTSUB, mov2textsub);
REGISTER_BSF(NOISE, noise);
REGISTER_BSF(REMOVE_EXTRADATA, remove_extradata);

88
libavcodec/mp3_header_compress_bsf.c
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@@ -1,88 +0,0 @@
/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "mpegaudiodecheader.h"
static int mp3_header_compress(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size, int keyframe){
uint32_t header, extraheader;
int mode_extension, header_size;
if(avctx->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL){
av_log(avctx, AV_LOG_ERROR, "not standards compliant\n");
return -1;
}
header = AV_RB32(buf);
mode_extension= (header>>4)&3;
if(ff_mpa_check_header(header) < 0 || (header&0x60000) != 0x20000){
output_unchanged:
*poutbuf= (uint8_t *) buf;
*poutbuf_size= buf_size;
av_log(avctx, AV_LOG_INFO, "cannot compress %08X\n", header);
return 0;
}
if(avctx->extradata_size == 0){
avctx->extradata_size=15;
avctx->extradata= av_malloc(avctx->extradata_size);
strcpy(avctx->extradata, "FFCMP3 0.0");
memcpy(avctx->extradata+11, buf, 4);
}
if(avctx->extradata_size != 15){
av_log(avctx, AV_LOG_ERROR, "Extradata invalid\n");
return -1;
}
extraheader = AV_RB32(avctx->extradata+11);
if((extraheader&MP3_MASK) != (header&MP3_MASK))
goto output_unchanged;
header_size= (header&0x10000) ? 4 : 6;
*poutbuf_size= buf_size - header_size;
*poutbuf= av_malloc(buf_size - header_size + FF_INPUT_BUFFER_PADDING_SIZE);
memcpy(*poutbuf, buf + header_size, buf_size - header_size + FF_INPUT_BUFFER_PADDING_SIZE);
if(avctx->channels==2){
if((header & (3<<19)) != 3<<19){
(*poutbuf)[1] &= 0x3F;
(*poutbuf)[1] |= mode_extension<<6;
FFSWAP(int, (*poutbuf)[1], (*poutbuf)[2]);
}else{
(*poutbuf)[1] &= 0x8F;
(*poutbuf)[1] |= mode_extension<<4;
}
}
return 1;
}
AVBitStreamFilter ff_mp3_header_compress_bsf={
"mp3comp",
0,
mp3_header_compress,
};

98
libavcodec/mp3_header_decompress_bsf.c
View File

@@ -1,98 +0,0 @@
/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/common.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "mpegaudiodecheader.h"
#include "mpegaudiodata.h"
static int mp3_header_decompress(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size, int keyframe){
uint32_t header;
int sample_rate= avctx->sample_rate;
int sample_rate_index=0;
int lsf, mpeg25, bitrate_index, frame_size;
header = AV_RB32(buf);
if(ff_mpa_check_header(header) >= 0){
*poutbuf= (uint8_t *) buf;
*poutbuf_size= buf_size;
return 0;
}
if(avctx->extradata_size != 15 || strcmp(avctx->extradata, "FFCMP3 0.0")){
av_log(avctx, AV_LOG_ERROR, "Extradata invalid %d\n", avctx->extradata_size);
return -1;
}
header= AV_RB32(avctx->extradata+11) & MP3_MASK;
lsf = sample_rate < (24000+32000)/2;
mpeg25 = sample_rate < (12000+16000)/2;
sample_rate_index= (header>>10)&3;
sample_rate= avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25); //in case sample rate is a little off
for(bitrate_index=2; bitrate_index<30; bitrate_index++){
frame_size = avpriv_mpa_bitrate_tab[lsf][2][bitrate_index>>1];
frame_size = (frame_size * 144000) / (sample_rate << lsf) + (bitrate_index&1);
if(frame_size == buf_size + 4)
break;
if(frame_size == buf_size + 6)
break;
}
if(bitrate_index == 30){
av_log(avctx, AV_LOG_ERROR, "Could not find bitrate_index.\n");
return -1;
}
header |= (bitrate_index&1)<<9;
header |= (bitrate_index>>1)<<12;
header |= (frame_size == buf_size + 4)<<16; //FIXME actually set a correct crc instead of 0
*poutbuf_size= frame_size;
*poutbuf= av_malloc(frame_size + FF_INPUT_BUFFER_PADDING_SIZE);
memcpy(*poutbuf + frame_size - buf_size, buf, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
if(avctx->channels==2){
uint8_t *p= *poutbuf + frame_size - buf_size;
if(lsf){
FFSWAP(int, p[1], p[2]);
header |= (p[1] & 0xC0)>>2;
p[1] &= 0x3F;
}else{
header |= p[1] & 0x30;
p[1] &= 0xCF;
}
}
AV_WB32(*poutbuf, header);
return 1;
}
AVBitStreamFilter ff_mp3_header_decompress_bsf={
"mp3decomp",
0,
mp3_header_decompress,
};