FFmpeg  4.4.5
luodatdec.c
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1 /*
2  * CCTV DAT demuxer
3  *
4  * Copyright (c) 2020 Paul B Mahol
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "libavutil/intreadwrite.h"
24 #include "avio_internal.h"
25 #include "avformat.h"
26 #include "internal.h"
27 
28 static int dat_probe(const AVProbeData *p)
29 {
30  if (p->buf_size < 0x2080)
31  return 0;
32 
33  if (memcmp(p->buf, "luo ", 4))
34  return 0;
35 
36  if (memcmp(p->buf + 0x1ffc, " oulliu ", 8))
37  return 0;
38 
39  if (!AV_RL32(p->buf + 0x2004))
40  return 0;
41 
42  if (memcmp(p->buf + 0x207c, " uil", 4))
43  return 0;
44 
45  return AVPROBE_SCORE_MAX;
46 }
47 
49 {
50  s->ctx_flags |= AVFMTCTX_NOHEADER;
51 
52  avio_seek(s->pb, 0x2000, SEEK_SET);
53 
54  return 0;
55 }
56 
58 {
59  AVIOContext *pb = s->pb;
60  int index, ret, key, stream_id, stream_index, width, height, fps, pkt_size;
61  int64_t pts, pos = avio_tell(pb);
62 
63  if (avio_feof(pb))
64  return AVERROR_EOF;
65 
66  if (avio_rb32(pb) != MKBETAG('l', 'i', 'u', ' '))
67  return AVERROR_INVALIDDATA;
68  stream_id = avio_rl32(pb);
69  width = avio_rl32(pb);
70  height = avio_rl32(pb);
71  fps = avio_rl32(pb);
72  avio_skip(pb, 16);
73  key = avio_rl32(pb) == 1;
74  avio_skip(pb, 4);
75  index = avio_rl32(pb);
76  avio_skip(pb, 4);
77  pts = avio_rl64(pb);
78  pkt_size = avio_rl32(pb);
79  avio_skip(pb, 64);
80 
81  if (pkt_size == 0)
82  return AVERROR_EOF;
83 
84  for (stream_index = 0; stream_index < s->nb_streams; stream_index++) {
85  if (s->streams[stream_index]->id == stream_id)
86  break;
87  }
88 
89  if (stream_index == s->nb_streams) {
91 
92  if (!st)
93  return AVERROR(ENOMEM);
94 
95  st->id = stream_id;
98  st->codecpar->width = width;
99  st->codecpar->height = height;
100  avpriv_set_pts_info(st, 64, 1, fps);
101  }
102 
103  if (index >= s->nb_streams)
104  av_log(s, AV_LOG_WARNING, "Stream index out of range.\n");
105 
106  ret = av_get_packet(pb, pkt, pkt_size);
107  if (ret < 0)
108  return ret;
109  pkt->pos = pos;
110  pkt->pts = pts;
111  pkt->stream_index = stream_index;
112  if (key)
114 
115  return ret;
116 }
117 
119  .name = "luodat",
120  .long_name = NULL_IF_CONFIG_SMALL("Video CCTV DAT"),
121  .read_probe = dat_probe,
122  .read_header = dat_read_header,
123  .read_packet = dat_read_packet,
124  .extensions = "dat",
125  .flags = AVFMT_GENERIC_INDEX,
126 };
Main libavformat public API header.
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
#define AVFMTCTX_NOHEADER
signal that no header is present (streams are added dynamically)
Definition: avformat.h:1177
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:310
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:463
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
int avio_feof(AVIOContext *s)
Similar to feof() but also returns nonzero on read errors.
Definition: aviobuf.c:364
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:337
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:750
unsigned int avio_rb32(AVIOContext *s)
Definition: aviobuf.c:781
uint64_t avio_rl64(AVIOContext *s)
Definition: aviobuf.c:758
#define AV_RL32
Definition: intreadwrite.h:146
#define s(width, name)
Definition: cbs_vp9.c:257
#define MKBETAG(a, b, c, d)
Definition: common.h:479
#define NULL
Definition: coverity.c:32
long long int64_t
Definition: coverity.c:34
@ AV_CODEC_ID_H264
Definition: codec_id.h:76
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:410
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4509
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
#define AVERROR_EOF
End of file.
Definition: error.h:55
#define AVERROR(e)
Definition: error.h:43
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:200
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
int index
Definition: gxfenc.c:89
const char * key
void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: utils.c:4945
common internal API header
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
static int dat_probe(const AVProbeData *p)
Definition: luodatdec.c:28
AVInputFormat ff_luodat_demuxer
Definition: luodatdec.c:118
static int dat_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: luodatdec.c:57
static int dat_read_header(AVFormatContext *s)
Definition: luodatdec.c:48
unsigned int pos
Definition: spdifenc.c:412
int width
Video only.
Definition: codec_par.h:126
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
Format I/O context.
Definition: avformat.h:1232
Bytestream IO Context.
Definition: avio.h:161
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:645
This structure stores compressed data.
Definition: packet.h:346
int stream_index
Definition: packet.h:371
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:375
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:362
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:389
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:444
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
Stream structure.
Definition: avformat.h:873
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1038
int id
Format-specific stream ID.
Definition: avformat.h:880
#define av_log(a,...)
AVPacket * pkt
Definition: movenc.c:59
#define height
#define width
static int64_t pts