FFmpeg
adxdec.c
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1 /*
2  * Copyright (c) 2011 Justin Ruggles
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * CRI ADX demuxer
24  */
25 
26 #include "libavutil/intreadwrite.h"
27 #include "avformat.h"
28 #include "internal.h"
29 
30 #define BLOCK_SIZE 18
31 #define BLOCK_SAMPLES 32
32 
33 typedef struct ADXDemuxerContext {
36 
37 static int adx_probe(const AVProbeData *p)
38 {
39  int offset;
40  if (AV_RB16(p->buf) != 0x8000)
41  return 0;
42  offset = AV_RB16(&p->buf[2]);
43  if ( offset < 8
44  || offset > p->buf_size - 4
45  || memcmp(p->buf + offset - 2, "(c)CRI", 6))
46  return 0;
47  return AVPROBE_SCORE_MAX * 3 / 4;
48 }
49 
51 {
53  AVCodecParameters *par = s->streams[0]->codecpar;
54  int ret, size;
55 
56  if (par->channels <= 0) {
57  av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", par->channels);
58  return AVERROR_INVALIDDATA;
59  }
60 
61  size = BLOCK_SIZE * par->channels;
62 
63  pkt->pos = avio_tell(s->pb);
64  pkt->stream_index = 0;
65 
66  ret = av_get_packet(s->pb, pkt, size);
67  if (ret != size) {
68  av_packet_unref(pkt);
69  return ret < 0 ? ret : AVERROR(EIO);
70  }
71  if (AV_RB16(pkt->data) & 0x8000) {
72  av_packet_unref(pkt);
73  return AVERROR_EOF;
74  }
75  pkt->size = size;
76  pkt->duration = 1;
77  pkt->pts = (pkt->pos - c->header_size) / size;
78 
79  return 0;
80 }
81 
83 {
85  AVCodecParameters *par;
86 
88  if (!st)
89  return AVERROR(ENOMEM);
90  par = s->streams[0]->codecpar;
91 
92  if (avio_rb16(s->pb) != 0x8000)
93  return AVERROR_INVALIDDATA;
94  c->header_size = avio_rb16(s->pb) + 4;
95  avio_seek(s->pb, -4, SEEK_CUR);
96 
97  if (ff_get_extradata(s, par, s->pb, c->header_size) < 0)
98  return AVERROR(ENOMEM);
99 
100  if (par->extradata_size < 12) {
101  av_log(s, AV_LOG_ERROR, "Invalid extradata size.\n");
102  return AVERROR_INVALIDDATA;
103  }
104  par->channels = AV_RB8 (par->extradata + 7);
105  par->sample_rate = AV_RB32(par->extradata + 8);
106 
107  if (par->channels <= 0) {
108  av_log(s, AV_LOG_ERROR, "invalid number of channels %d\n", par->channels);
109  return AVERROR_INVALIDDATA;
110  }
111 
112  if (par->sample_rate <= 0) {
113  av_log(s, AV_LOG_ERROR, "Invalid sample rate %d\n", par->sample_rate);
114  return AVERROR_INVALIDDATA;
115  }
116 
118  par->codec_id = s->iformat->raw_codec_id;
119  par->bit_rate = (int64_t)par->sample_rate * par->channels * BLOCK_SIZE * 8LL / BLOCK_SAMPLES;
120 
122 
123  return 0;
124 }
125 
127  .name = "adx",
128  .long_name = NULL_IF_CONFIG_SMALL("CRI ADX"),
129  .read_probe = adx_probe,
130  .priv_data_size = sizeof(ADXDemuxerContext),
133  .extensions = "adx",
134  .raw_codec_id = AV_CODEC_ID_ADPCM_ADX,
136 };
#define NULL
Definition: coverity.c:32
#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:1500
static int adx_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: adxdec.c:50
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:4926
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3968
int size
Definition: avcodec.h:1481
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:246
static AVPacket pkt
unsigned int avio_rb16(AVIOContext *s)
Definition: aviobuf.c:788
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:87
#define BLOCK_SAMPLES
Definition: adxdec.c:31
This struct describes the properties of an encoded stream.
Definition: avcodec.h:3960
Format I/O context.
Definition: avformat.h:1358
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1498
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4499
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_RB32
Definition: bytestream.h:87
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
uint8_t * data
Definition: avcodec.h:1480
#define AVERROR_EOF
End of file.
Definition: error.h:55
static int adx_read_header(AVFormatContext *s)
Definition: adxdec.c:82
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
ptrdiff_t size
Definition: opengl_enc.c:100
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
#define av_log(a,...)
int64_t bit_rate
The average bitrate of the encoded data (in bits per second).
Definition: avcodec.h:3997
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define BLOCK_SIZE
Definition: adxdec.c:30
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
ff_const59 struct AVInputFormat * iformat
The input container format.
Definition: avformat.h:1370
enum AVMediaType codec_type
General type of the encoded data.
Definition: avcodec.h:3964
int extradata_size
Size of the extradata content in bytes.
Definition: avcodec.h:3986
int buf_size
Size of buf except extra allocated bytes.
Definition: avformat.h:449
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
static int adx_probe(const AVProbeData *p)
Definition: adxdec.c:37
#define s(width, name)
Definition: cbs_vp9.c:257
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_reading.c:42
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_WB16 unsigned int_TMPL AV_RB8
Definition: bytestream.h:87
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
#define AVFMT_GENERIC_INDEX
Use generic index building code.
Definition: avformat.h:468
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int raw_codec_id
Raw demuxers store their codec ID here.
Definition: avformat.h:700
#define flags(name, subs,...)
Definition: cbs_av1.c:561
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size)
Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end which is always set to 0 and f...
Definition: utils.c:3339
void * priv_data
Format private data.
Definition: avformat.h:1386
uint8_t * extradata
Extra binary data needed for initializing the decoder, codec-dependent.
Definition: avcodec.h:3982
int channels
Audio only.
Definition: avcodec.h:4074
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1482
AVInputFormat ff_adx_demuxer
Definition: adxdec.c:126
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
This structure stores compressed data.
Definition: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473