FFmpeg
ingenientdec.c
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1 /*
2  * RAW Ingenient MJPEG demuxer
3  * Copyright (c) 2005 Alex Beregszaszi
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avformat.h"
23 #include "rawdec.h"
24 #include "libavutil/intreadwrite.h"
25 
26 // http://multimedia.cx/ingenient.txt
27 static int ingenient_probe(const AVProbeData *p)
28 {
29  if ( AV_RN32(p->buf) != AV_RN32("MJPG")
30  || p->buf_size < 50
31  || AV_RB16(p->buf + 48) != 0xffd8)
32  return 0;
33  return AVPROBE_SCORE_MAX * 3 / 4;
34 }
35 
37 {
38  int ret, size, w, h, unk1, unk2;
39 
40  if (avio_rl32(s->pb) != MKTAG('M', 'J', 'P', 'G'))
41  return AVERROR(EIO); // FIXME
42 
43  size = avio_rl32(s->pb);
44 
45  w = avio_rl16(s->pb);
46  h = avio_rl16(s->pb);
47 
48  avio_skip(s->pb, 8); // zero + size (padded?)
49  avio_skip(s->pb, 2);
50  unk1 = avio_rl16(s->pb);
51  unk2 = avio_rl16(s->pb);
52  avio_skip(s->pb, 22); // ASCII timestamp
53 
54  av_log(s, AV_LOG_DEBUG, "Ingenient packet: size=%d, width=%d, height=%d, unk1=%d unk2=%d\n",
55  size, w, h, unk1, unk2);
56 
57  ret = av_get_packet(s->pb, pkt, size);
58  if (ret < 0)
59  return ret;
60  pkt->stream_index = 0;
61  return ret;
62 }
63 
65 
67  .name = "ingenient",
68  .long_name = NULL_IF_CONFIG_SMALL("raw Ingenient MJPEG"),
69  .priv_data_size = sizeof(FFRawVideoDemuxerContext),
74  .extensions = "cgi", // FIXME
75  .raw_codec_id = AV_CODEC_ID_MJPEG,
76  .priv_class = &ingenient_demuxer_class,
77 };
ff_raw_video_read_header
int ff_raw_video_read_header(AVFormatContext *s)
Definition: rawdec.c:71
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:406
w
uint8_t w
Definition: llviddspenc.c:38
AVProbeData::buf_size
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
avio_rl16
unsigned int avio_rl16(AVIOContext *s)
Definition: aviobuf.c:731
ingenient_read_packet
static int ingenient_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: ingenientdec.c:36
ff_ingenient_demuxer
AVInputFormat ff_ingenient_demuxer
Definition: ingenientdec.c:66
AVInputFormat
Definition: avformat.h:636
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:641
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
AV_LOG_DEBUG
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
AVFormatContext
Format I/O context.
Definition: avformat.h:1335
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
rawdec.h
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
AV_RN32
#define AV_RN32(p)
Definition: intreadwrite.h:364
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:747
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:188
size
int size
Definition: twinvq_data.h:11134
FFRawVideoDemuxerContext
Definition: rawdec.h:29
AV_CODEC_ID_MJPEG
@ AV_CODEC_ID_MJPEG
Definition: codec_id.h:56
ingenient_probe
static int ingenient_probe(const AVProbeData *p)
Definition: ingenientdec.c:27
av_get_packet
int av_get_packet(AVIOContext *s, AVPacket *pkt, int size)
Allocate and read the payload of a packet and initialize its fields with default values.
Definition: utils.c:307
ret
ret
Definition: filter_design.txt:187
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
avformat.h
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
FF_RAWVIDEO_DEMUXER_CLASS
#define FF_RAWVIDEO_DEMUXER_CLASS(name)
Definition: rawdec.h:63
AVPacket::stream_index
int stream_index
Definition: packet.h:357
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:329
AVPacket
This structure stores compressed data.
Definition: packet.h:332
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:565
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
h
h
Definition: vp9dsp_template.c:2038
AV_RB16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_WB32 unsigned int_TMPL AV_WB24 unsigned int_TMPL AV_RB16
Definition: bytestream.h:94