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/*
* VC-1 demuxer
* Copyright (c) 2015 Carl Eugen Hoyos
*
* 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"
#include "libavutil/intreadwrite.h"
#include "libavcodec/vc1_common.h"
static int vc1_probe(const AVProbeData *p)
{
int seq = 0, entry = 0, invalid = 0, frame = 0, i;
for (i = 0; i < p->buf_size + 5; i++) {
uint32_t code = AV_RB32(p->buf + i);
if ((code & 0xffffffe0) == 0x100) {
int type = code & 0x11f;
i += 4;
switch (type) {
case VC1_CODE_SEQHDR: {
int profile, level, chromaformat;
profile = (p->buf[i] & 0xc0) >> 6;
if (profile != PROFILE_ADVANCED) {
seq = 0;
invalid++;
continue;
}
level = (p->buf[i] & 0x38) >> 3;
if (level >= 5) {
seq = 0;
invalid++;
continue;
}
chromaformat = (p->buf[i] & 0x6) >> 1;
if (chromaformat != 1) {
seq = 0;
invalid++;
continue;
}
seq++;
i += 6;
break;
}
case VC1_CODE_ENTRYPOINT:
if (!seq) {
invalid++;
continue;
}
entry++;
i += 2;
break;
case VC1_CODE_FRAME:
case VC1_CODE_FIELD:
case VC1_CODE_SLICE:
if (seq && entry)
frame++;
break;
}
}
}
if (frame > 1 && frame >> 1 > invalid)
return AVPROBE_SCORE_EXTENSION / 2 + 1;
if (frame >= 1)
return AVPROBE_SCORE_EXTENSION / 4;
return 0;
}
FF_DEF_RAWVIDEO_DEMUXER2(vc1, "raw VC-1", vc1_probe, "vc1", AV_CODEC_ID_VC1, AVFMT_GENERIC_INDEX|AVFMT_NOTIMESTAMPS)
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