FFmpeg/libavformat/vc1test.c
Andreas Rheinhardt c1e439d7e9 avformat: Forward errors where possible
It is not uncommon to find code where the caller thinks to know better
what the return value should be than the callee. E.g. something like
"if (av_new_packet(pkt, size) < 0) return AVERROR(ENOMEM);". This commit
changes several instances of this to instead forward the actual error.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2019-12-12 19:25:33 +01:00

128 lines
3.4 KiB
C

/*
* VC1 Test Bitstreams Format Demuxer
* Copyright (c) 2006, 2008 Konstantin Shishkov
*
* 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
*/
/**
* @file
* VC1 test bitstream file demuxer
* by Konstantin Shishkov
* Format specified in SMPTE standard 421 Annex L
*/
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define VC1_EXTRADATA_SIZE 4
static int vc1t_probe(const AVProbeData *p)
{
uint32_t size;
if (p->buf_size < 24)
return 0;
size = AV_RL32(&p->buf[4]);
if (p->buf[3] != 0xC5 || size < 4 || size > p->buf_size - 20 ||
AV_RL32(&p->buf[size+16]) != 0xC)
return 0;
return AVPROBE_SCORE_EXTENSION;
}
static int vc1t_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
AVStream *st;
int frames, ret;
uint32_t fps;
uint32_t size;
frames = avio_rl24(pb);
if (avio_r8(pb) != 0xC5 || ((size = avio_rl32(pb)) < 4))
return AVERROR_INVALIDDATA;
/* init video codec */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_WMV3;
if ((ret = ff_get_extradata(s, st->codecpar, pb, VC1_EXTRADATA_SIZE)) < 0)
return ret;
avio_skip(pb, size - 4);
st->codecpar->height = avio_rl32(pb);
st->codecpar->width = avio_rl32(pb);
if(avio_rl32(pb) != 0xC)
return AVERROR_INVALIDDATA;
avio_skip(pb, 8);
fps = avio_rl32(pb);
if(fps == 0xFFFFFFFF)
avpriv_set_pts_info(st, 32, 1, 1000);
else{
if (!fps) {
av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
fps = 1;
}
avpriv_set_pts_info(st, 24, 1, fps);
st->duration = frames;
}
return 0;
}
static int vc1t_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
AVIOContext *pb = s->pb;
int frame_size;
int keyframe = 0;
uint32_t pts;
if(avio_feof(pb))
return AVERROR(EIO);
frame_size = avio_rl24(pb);
if(avio_r8(pb) & 0x80)
keyframe = 1;
pts = avio_rl32(pb);
if(av_get_packet(pb, pkt, frame_size) < 0)
return AVERROR(EIO);
if(s->streams[0]->time_base.den == 1000)
pkt->pts = pts;
pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;
pkt->pos -= 8;
return pkt->size;
}
AVInputFormat ff_vc1t_demuxer = {
.name = "vc1test",
.long_name = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),
.read_probe = vc1t_probe,
.read_header = vc1t_read_header,
.read_packet = vc1t_read_packet,
.extensions = "rcv",
.flags = AVFMT_GENERIC_INDEX,
};