forked from KolibriOS/kolibrios
66 lines
2.0 KiB
C
66 lines
2.0 KiB
C
/*
|
|
* 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;
|
|
}
|
|
}
|
|
if(valid_psc > 2*invalid_psc + 2*res_change + 3){
|
|
return AVPROBE_SCORE_EXTENSION;
|
|
}else if(valid_psc > 2*invalid_psc)
|
|
return AVPROBE_SCORE_EXTENSION / 2;
|
|
return 0;
|
|
}
|
|
|
|
FF_DEF_RAWVIDEO_DEMUXER(h263, "raw H.263", h263_probe, NULL, AV_CODEC_ID_H263)
|