mirror of
https://github.com/librempeg/librempeg
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81 lines
2.4 KiB
C
81 lines
2.4 KiB
C
/*
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* RAW H.264 video demuxer
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* Copyright (c) 2008 Michael Niedermayer <michaelni@gmx.at>
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*
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* This file is part of FFmpeg.
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*
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* FFmpeg is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation; either
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* version 2.1 of the License, or (at your option) any later version.
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*
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* FFmpeg is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with FFmpeg; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#include "avformat.h"
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#include "raw.h"
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static int h264_probe(AVProbeData *p)
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{
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uint32_t code= -1;
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int sps=0, pps=0, idr=0, res=0, sli=0;
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int i;
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for(i=0; i<p->buf_size; i++){
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code = (code<<8) + p->buf[i];
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if ((code & 0xffffff00) == 0x100) {
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int ref_idc= (code>>5)&3;
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int type = code & 0x1F;
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static const int8_t ref_zero[32]={
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2, 0, 0, 0, 0,-1, 1,-1,
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-1, 1, 1, 1, 1,-1, 2, 2,
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2, 2, 2, 0, 2, 2, 2, 2,
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2, 2, 2, 2, 2, 2, 2, 2
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};
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if(code & 0x80) //forbidden bit
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return 0;
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if(ref_zero[type] == 1 && ref_idc)
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return 0;
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if(ref_zero[type] ==-1 && !ref_idc)
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return 0;
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if(ref_zero[type] == 2)
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res++;
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switch(type){
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case 1: sli++; break;
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case 5: idr++; break;
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case 7:
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if(p->buf[i+2]&0x0F)
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return 0;
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sps++;
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break;
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case 8: pps++; break;
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}
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}
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}
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if(sps && pps && (idr||sli>3) && res<(sps+pps+idr))
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return AVPROBE_SCORE_MAX/2+1; // +1 for .mpg
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return 0;
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}
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AVInputFormat h264_demuxer = {
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"h264",
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NULL_IF_CONFIG_SMALL("raw H.264 video format"),
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0,
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h264_probe,
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ff_raw_video_read_header,
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ff_raw_read_partial_packet,
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.flags= AVFMT_GENERIC_INDEX,
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.extensions = "h26l,h264,264", //FIXME remove after writing mpeg4_probe
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.value = CODEC_ID_H264,
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};
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