mirror of https://github.com/FFmpeg/FFmpeg.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
77 lines
2.4 KiB
77 lines
2.4 KiB
/* |
|
* RAW H.263 video demuxer |
|
* Copyright (c) 2009 Michael Niedermayer <michaelni@gmx.at> |
|
* |
|
* 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 |
|
*/ |
|
|
|
#include "avformat.h" |
|
#include "rawdec.h" |
|
|
|
static int h263_probe(AVProbeData *p) |
|
{ |
|
uint64_t code= -1; |
|
int i; |
|
int valid_psc=0; |
|
int invalid_psc=0; |
|
int res_change=0; |
|
int src_fmt, last_src_fmt=-1; |
|
int last_gn=0; |
|
|
|
for(i=0; i<p->buf_size; i++){ |
|
code = (code<<8) + p->buf[i]; |
|
if ((code & 0xfffffc0000) == 0x800000) { |
|
src_fmt= (code>>2)&3; |
|
if( src_fmt != last_src_fmt |
|
&& last_src_fmt>0 && last_src_fmt<6 |
|
&& src_fmt<6) |
|
res_change++; |
|
|
|
if((code&0x300)==0x200 && src_fmt){ |
|
valid_psc++; |
|
last_gn=0; |
|
}else |
|
invalid_psc++; |
|
last_src_fmt= src_fmt; |
|
} else if((code & 0xffff800000) == 0x800000) { |
|
int gn= (code>>(23-5)) & 0x1F; |
|
if(gn<last_gn){ |
|
invalid_psc++; |
|
}else |
|
last_gn= gn; |
|
} |
|
} |
|
//av_log(NULL, AV_LOG_ERROR, "h263_probe: psc:%d invalid:%d res_change:%d\n", valid_psc, invalid_psc, res_change); |
|
//h263_probe: psc:3 invalid:0 res_change:0 (1588/recent_ffmpeg_parses_mpg_incorrectly.mpg) |
|
if(valid_psc > 2*invalid_psc + 2*res_change + 3){ |
|
return 50; |
|
}else if(valid_psc > 2*invalid_psc) |
|
return 25; |
|
return 0; |
|
} |
|
|
|
AVInputFormat h263_demuxer = { |
|
"h263", |
|
NULL_IF_CONFIG_SMALL("raw H.263"), |
|
0, |
|
h263_probe, |
|
ff_raw_video_read_header, |
|
ff_raw_read_partial_packet, |
|
.flags= AVFMT_GENERIC_INDEX, |
|
// .extensions = "h263", //FIXME remove after writing mpeg4_probe |
|
.value = CODEC_ID_H263, |
|
};
|
|
|