FFmpeg
sdr2.c
Go to the documentation of this file.
1 /*
2  * SDR2 demuxer
3  * Copyright (c) 2014 Paul B Mahol
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 "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "internal.h"
25 
26 static int sdr2_probe(const AVProbeData *p)
27 {
28  if (AV_RL32(p->buf) != MKTAG('S', 'R', 'A', 1))
29  return 0;
30 
32 }
33 
34 #define FIRST 0xA8
35 
37 {
38  AVStream *st, *ast;
39 
40  ast = avformat_new_stream(s, 0);
41  if (!ast)
42  return AVERROR(ENOMEM);
43 
44  st = avformat_new_stream(s, 0);
45  if (!st)
46  return AVERROR(ENOMEM);
47 
48  avio_skip(s->pb, 20);
49  avpriv_set_pts_info(st, 64, 1, avio_rl32(s->pb));
51  st->codecpar->width = avio_rl32(s->pb);
52  st->codecpar->height = avio_rl32(s->pb);
55 
57  ast->codecpar->ch_layout.nb_channels = 1;
58  ast->codecpar->sample_rate = 8000;
60  avpriv_set_pts_info(ast, 64, 1, 8000);
61 
62  avio_seek(s->pb, FIRST, SEEK_SET);
63 
64  return 0;
65 }
66 
67 static const uint8_t header[24] = {
68  0x00, 0x00, 0x00, 0x01, 0x67, 0x42, 0x00, 0x1e,
69  0xa6, 0x80, 0xb0, 0x7e, 0x40, 0x00, 0x00, 0x00,
70  0x01, 0x68, 0xce, 0x38, 0x80, 0x00, 0x00, 0x00
71 };
72 
74 {
75  int64_t pos;
76  unsigned next;
77  int flags, ret = 0, is_video;
78 
79  pos = avio_tell(s->pb);
80 
81  flags = avio_rl32(s->pb);
82  avio_skip(s->pb, 4);
83 
84  next = avio_rl32(s->pb);
85  if (next <= 52)
86  return AVERROR_INVALIDDATA;
87 
88  avio_skip(s->pb, 6);
89  is_video = avio_rl32(s->pb);
90  avio_skip(s->pb, 30);
91 
92  if (pos == FIRST) {
93  if ((ret = av_new_packet(pkt, next - 52 + 24)) < 0)
94  return ret;
95  memcpy(pkt->data, header, 24);
96  ret = avio_read(s->pb, pkt->data + 24, next - 52);
97  if (ret < 0) {
98  return ret;
99  }
100  av_shrink_packet(pkt, ret + 24);
101  } else {
102  ret = av_get_packet(s->pb, pkt, next - 52);
103  }
104  pkt->stream_index = !!is_video;
105  pkt->pos = pos;
106  if (flags & (1 << 12))
108 
109  return ret;
110 }
111 
113  .name = "sdr2",
114  .long_name = NULL_IF_CONFIG_SMALL("SDR2"),
115  .read_probe = sdr2_probe,
116  .read_header = sdr2_read_header,
117  .read_packet = sdr2_read_packet,
118  .extensions = "sdr2",
119  .flags = AVFMT_GENERIC_INDEX,
120 };
AV_CODEC_ID_PCM_S16LE
@ AV_CODEC_ID_PCM_S16LE
Definition: codec_id.h:326
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
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: options.c:243
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:58
AVPacket::data
uint8_t * data
Definition: packet.h:374
AVChannelLayout::nb_channels
int nb_channels
Number of channels in this layout.
Definition: channel_layout.h:311
sdr2_probe
static int sdr2_probe(const AVProbeData *p)
Definition: sdr2.c:26
AV_PKT_FLAG_KEY
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:429
FIRST
#define FIRST
Definition: sdr2.c:34
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:771
sdr2_read_packet
static int sdr2_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sdr2.c:73
ffstream
static av_always_inline FFStream * ffstream(AVStream *st)
Definition: internal.h:413
av_shrink_packet
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:112
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:500
AVFMT_GENERIC_INDEX
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:480
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:546
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:256
av_new_packet
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:97
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:551
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
AVCodecParameters::width
int width
Video only.
Definition: codec_par.h:128
AV_CODEC_ID_H264
@ AV_CODEC_ID_H264
Definition: codec_id.h:79
FFStream::need_parsing
enum AVStreamParseType need_parsing
Definition: internal.h:386
AVFormatContext
Format I/O context.
Definition: avformat.h:1104
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:861
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:213
AVPROBE_SCORE_EXTENSION
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:461
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:178
avio_rl32
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:751
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:115
header
static const uint8_t header[24]
Definition: sdr2.c:67
AVPacket::flags
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:380
sdr2_read_header
static int sdr2_read_header(AVFormatContext *s)
Definition: sdr2.c:36
AVCodecParameters::height
int height
Definition: codec_par.h:129
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:102
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:838
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:252
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:633
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:339
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:62
AVPacket
This structure stores compressed data.
Definition: packet.h:351
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
AVSTREAM_PARSE_FULL
@ AVSTREAM_PARSE_FULL
full parsing and repack
Definition: avformat.h:688
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
MKTAG
#define MKTAG(a, b, c, d)
Definition: macros.h:55
ff_sdr2_demuxer
const AVInputFormat ff_sdr2_demuxer
Definition: sdr2.c:112