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/*
* RAW MPEG-4 video demuxer
* Copyright (c) 2006 Thijs Vermeir <thijs.vermeir@barco.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 "avformat.h"
#include "rawdec.h"
#define VISUAL_OBJECT_START_CODE 0x000001b5
#define VOP_START_CODE 0x000001b6
static int mpeg4video_probe(AVProbeData *probe_packet)
{
uint32_t temp_buffer= -1;
int VO=0, VOL=0, VOP = 0, VISO = 0, res=0;
int i;
for(i=0; i<probe_packet->buf_size; i++){
temp_buffer = (temp_buffer<<8) + probe_packet->buf[i];
if ((temp_buffer & 0xffffff00) != 0x100)
continue;
if (temp_buffer == VOP_START_CODE) VOP++;
else if (temp_buffer == VISUAL_OBJECT_START_CODE) VISO++;
else if (temp_buffer < 0x120) VO++;
else if (temp_buffer < 0x130) VOL++;
else if ( !(0x1AF < temp_buffer && temp_buffer < 0x1B7)
&& !(0x1B9 < temp_buffer && temp_buffer < 0x1C4)) res++;
}
if (VOP >= VISO && VOP >= VOL && VO >= VOL && VOL > 0 && res==0)
return VOP+VO > 3 ? AVPROBE_SCORE_MAX/2 : AVPROBE_SCORE_MAX/4;
return 0;
}
AVInputFormat ff_m4v_demuxer = {
"m4v",
NULL_IF_CONFIG_SMALL("raw MPEG-4 video format"),
0,
mpeg4video_probe, /** probing for MPEG-4 data */
ff_raw_video_read_header,
ff_raw_read_partial_packet,
.flags= AVFMT_GENERIC_INDEX,
.extensions = "m4v",
.value = CODEC_ID_MPEG4,
};
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