FFmpeg
sdr2.c
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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(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->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 (av_new_packet(pkt, next - 52 + 24) < 0)
94  return AVERROR(ENOMEM);
95  memcpy(pkt->data, header, 24);
96  ret = avio_read(s->pb, pkt->data + 24, next - 52);
97  if (ret < 0) {
98  av_packet_unref(pkt);
99  return ret;
100  }
101  av_shrink_packet(pkt, ret + 24);
102  } else {
103  ret = av_get_packet(s->pb, pkt, next - 52);
104  }
105  pkt->stream_index = !!is_video;
106  pkt->pos = pos;
107  if (flags & (1 << 12))
108  pkt->flags |= AV_PKT_FLAG_KEY;
109 
110  return ret;
111 }
112 
114  .name = "sdr2",
115  .long_name = NULL_IF_CONFIG_SMALL("SDR2"),
116  .read_probe = sdr2_probe,
117  .read_header = sdr2_read_header,
118  .read_packet = sdr2_read_packet,
119  .extensions = "sdr2",
120  .flags = AVFMT_GENERIC_INDEX,
121 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1488
void av_shrink_packet(AVPacket *pkt, int size)
Reduce packet size, correctly zeroing padding.
Definition: avpacket.c:101
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:4882
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3944
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:331
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1351
uint8_t
int width
Video only.
Definition: avcodec.h:4010
enum AVStreamParseType need_parsing
Definition: avformat.h:1092
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4455
uint8_t * data
Definition: avcodec.h:1468
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
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
static const uint8_t header[24]
Definition: sdr2.c:67
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:648
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1500
int av_new_packet(AVPacket *pkt, int size)
Allocate the payload of a packet and initialize its fields with default values.
Definition: avpacket.c:86
unsigned int avio_rl32(AVIOContext *s)
Definition: aviobuf.c:770
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3940
AVInputFormat ff_sdr2_demuxer
Definition: sdr2.c:113
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1474
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:450
#define s(width, name)
Definition: cbs_vp9.c:257
Stream structure.
Definition: avformat.h:874
AVIOContext * pb
I/O context.
Definition: avformat.h:1393
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:598
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:470
#define AVPROBE_SCORE_EXTENSION
score for file extension
Definition: avformat.h:458
This structure contains the data a format has to probe a file.
Definition: avformat.h:448
#define flags(name, subs,...)
Definition: cbs_av1.c:606
int sample_rate
Audio only.
Definition: avcodec.h:4054
full parsing and repack
Definition: avformat.h:793
Main libavformat public API header.
static int sdr2_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: sdr2.c:73
static int sdr2_probe(AVProbeData *p)
Definition: sdr2.c:26
int channels
Audio only.
Definition: avcodec.h:4050
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:647
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1021
static int sdr2_read_header(AVFormatContext *s)
Definition: sdr2.c:36
int stream_index
Definition: avcodec.h:1470
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
#define MKTAG(a, b, c, d)
Definition: common.h:366
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1445
#define FIRST
Definition: sdr2.c:34