ffmpeg/libavformat/hevcdec.c

65 lines
2.0 KiB
C

/*
* RAW HEVC video demuxer
* Copyright (c) 2013 Dirk Farin <dirk.farin@gmail.com>
*
* 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 "libavcodec/hevc.h"
#include "avformat.h"
#include "rawdec.h"
static int hevc_probe(const AVProbeData *p)
{
uint32_t code = -1;
int vps = 0, sps = 0, pps = 0, irap = 0;
int i;
for (i = 0; i < p->buf_size - 1; i++) {
code = (code << 8) + p->buf[i];
if ((code & 0xffffff00) == 0x100) {
uint8_t nal2 = p->buf[i + 1];
int type = (code & 0x7E) >> 1;
if (code & 0x81) // forbidden and reserved zero bits
return 0;
if (nal2 & 0xf8) // reserved zero
return 0;
switch (type) {
case HEVC_NAL_VPS: vps++; break;
case HEVC_NAL_SPS: sps++; break;
case HEVC_NAL_PPS: pps++; break;
case HEVC_NAL_BLA_N_LP:
case HEVC_NAL_BLA_W_LP:
case HEVC_NAL_BLA_W_RADL:
case HEVC_NAL_CRA_NUT:
case HEVC_NAL_IDR_N_LP:
case HEVC_NAL_IDR_W_RADL: irap++; break;
}
}
}
if (vps && sps && pps && irap)
return AVPROBE_SCORE_EXTENSION + 1; // 1 more than .mpg
return 0;
}
FF_DEF_RAWVIDEO_DEMUXER(hevc, "raw HEVC video", hevc_probe, "hevc,h265,265", AV_CODEC_ID_HEVC)