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libavformat
vc1test.c
Go to the documentation of this file.
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/*
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* VC1 Test Bitstreams Format Demuxer
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* Copyright (c) 2006, 2008 Konstantin Shishkov
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*
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* This file is part of Libav.
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*
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* Libav 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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* Libav 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 Libav; 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 "
libavutil/intreadwrite.h
"
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#include "
avformat.h
"
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#include "
internal.h
"
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#define VC1_EXTRADATA_SIZE 4
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static
int
vc1t_probe
(
AVProbeData
*p)
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{
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if
(p->
buf_size
< 24)
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return
0;
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if
(p->
buf
[3] != 0xC5 ||
AV_RL32
(&p->
buf
[4]) != 4 ||
AV_RL32
(&p->
buf
[20]) != 0xC)
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return
0;
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return
AVPROBE_SCORE_MAX
/2;
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}
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static
int
vc1t_read_header
(
AVFormatContext
*s,
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AVFormatParameters
*ap)
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{
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AVIOContext
*pb = s->
pb
;
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AVStream
*st;
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int
frames;
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uint32_t fps;
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frames =
avio_rl24
(pb);
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if
(
avio_r8
(pb) != 0xC5 ||
avio_rl32
(pb) != 4)
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return
-1;
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/* init video codec */
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st =
avformat_new_stream
(s,
NULL
);
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if
(!st)
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return
-1;
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st->
codec
->
codec_type
=
AVMEDIA_TYPE_VIDEO
;
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st->
codec
->
codec_id
=
CODEC_ID_WMV3
;
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st->
codec
->
extradata
=
av_malloc
(
VC1_EXTRADATA_SIZE
);
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st->
codec
->
extradata_size
=
VC1_EXTRADATA_SIZE
;
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avio_read
(pb, st->
codec
->
extradata
,
VC1_EXTRADATA_SIZE
);
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st->
codec
->
height
=
avio_rl32
(pb);
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st->
codec
->
width
=
avio_rl32
(pb);
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if
(
avio_rl32
(pb) != 0xC)
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return
-1;
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avio_skip
(pb, 8);
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fps =
avio_rl32
(pb);
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if
(fps == 0xFFFFFFFF)
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avpriv_set_pts_info
(st, 32, 1, 1000);
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else
{
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if
(!fps) {
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av_log
(s,
AV_LOG_ERROR
,
"Zero FPS specified, defaulting to 1 FPS\n"
);
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fps = 1;
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}
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avpriv_set_pts_info
(st, 24, 1, fps);
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st->
duration
= frames;
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}
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return
0;
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}
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static
int
vc1t_read_packet
(
AVFormatContext
*s,
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AVPacket
*pkt)
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{
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AVIOContext
*pb = s->
pb
;
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int
frame_size;
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int
keyframe = 0;
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uint32_t pts;
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if
(pb->
eof_reached
)
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return
AVERROR
(EIO);
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frame_size =
avio_rl24
(pb);
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if
(
avio_r8
(pb) & 0x80)
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keyframe = 1;
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pts =
avio_rl32
(pb);
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if
(
av_get_packet
(pb, pkt, frame_size) < 0)
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return
AVERROR
(EIO);
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if
(s->
streams
[0]->
time_base
.
den
== 1000)
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pkt->
pts
= pts;
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pkt->
flags
|= keyframe ?
AV_PKT_FLAG_KEY
: 0;
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pkt->
pos
-= 8;
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return
pkt->
size
;
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}
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AVInputFormat
ff_vc1t_demuxer
= {
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.
name
=
"vc1test"
,
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.long_name =
NULL_IF_CONFIG_SMALL
(
"VC-1 test bitstream format"
),
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.read_probe =
vc1t_probe
,
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.read_header =
vc1t_read_header
,
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.read_packet =
vc1t_read_packet
,
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.flags =
AVFMT_GENERIC_INDEX
,
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};