/* * 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 50; }else if(valid_psc > 2*invalid_psc) return 25; return 0; } FF_DEF_RAWVIDEO_DEMUXER(h263, "raw H.263", h263_probe, NULL, AV_CODEC_ID_H263)