FFmpeg
dss.c
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1 /*
2  * Digital Speech Standard (DSS) demuxer
3  * Copyright (c) 2014 Oleksij Rempel <linux@rempel-privat.de>
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 
23 #include "libavutil/intreadwrite.h"
24 
25 #include "avformat.h"
26 #include "internal.h"
27 
28 #define DSS_HEAD_OFFSET_AUTHOR 0xc
29 #define DSS_AUTHOR_SIZE 16
30 
31 #define DSS_HEAD_OFFSET_START_TIME 0x26
32 #define DSS_HEAD_OFFSET_END_TIME 0x32
33 #define DSS_TIME_SIZE 12
34 
35 #define DSS_HEAD_OFFSET_ACODEC 0x2a4
36 #define DSS_ACODEC_DSS_SP 0x0 /* SP mode */
37 #define DSS_ACODEC_G723_1 0x2 /* LP mode */
38 
39 #define DSS_HEAD_OFFSET_COMMENT 0x31e
40 #define DSS_COMMENT_SIZE 64
41 
42 #define DSS_BLOCK_SIZE 512
43 #define DSS_AUDIO_BLOCK_HEADER_SIZE 6
44 #define DSS_FRAME_SIZE 42
45 
46 static const uint8_t frame_size[4] = { 24, 20, 4, 1 };
47 
48 typedef struct DSSDemuxContext {
49  unsigned int audio_codec;
50  int counter;
51  int swap;
53 
57 
58 static int dss_probe(const AVProbeData *p)
59 {
60  if ( AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')
61  && AV_RL32(p->buf) != MKTAG(0x3, 'd', 's', 's'))
62  return 0;
63 
64  return AVPROBE_SCORE_MAX;
65 }
66 
67 static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
68  const char *key)
69 {
70  AVIOContext *pb = s->pb;
71  char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 };
72  int y, month, d, h, minute, sec;
73  int ret;
74 
75  avio_seek(pb, offset, SEEK_SET);
76 
77  ret = avio_read(s->pb, string, DSS_TIME_SIZE);
78  if (ret < DSS_TIME_SIZE)
79  return ret < 0 ? ret : AVERROR_EOF;
80 
81  if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6)
82  return AVERROR_INVALIDDATA;
83  /* We deal with a two-digit year here, so set the default date to 2000
84  * and hope it will never be used in the next century. */
85  snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
86  y + 2000, month, d, h, minute, sec);
87  return av_dict_set(&s->metadata, key, datetime, 0);
88 }
89 
91  unsigned int size, const char *key)
92 {
93  AVIOContext *pb = s->pb;
94  char *value;
95  int ret;
96 
97  avio_seek(pb, offset, SEEK_SET);
98 
99  value = av_mallocz(size + 1);
100  if (!value)
101  return AVERROR(ENOMEM);
102 
103  ret = avio_read(s->pb, value, size);
104  if (ret < size) {
105  av_free(value);
106  return ret < 0 ? ret : AVERROR_EOF;
107  }
108 
109  return av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
110 }
111 
113 {
114  DSSDemuxContext *ctx = s->priv_data;
115  AVIOContext *pb = s->pb;
116  AVStream *st;
117  int ret, version;
118 
119  st = avformat_new_stream(s, NULL);
120  if (!st)
121  return AVERROR(ENOMEM);
122 
123  version = avio_r8(pb);
124  ctx->dss_header_size = version * DSS_BLOCK_SIZE;
125 
127  DSS_AUTHOR_SIZE, "author");
128  if (ret)
129  return ret;
130 
132  if (ret)
133  return ret;
134 
136  DSS_COMMENT_SIZE, "comment");
137  if (ret)
138  return ret;
139 
140  avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
141  ctx->audio_codec = avio_r8(pb);
142 
145  st->codecpar->sample_rate = 11025;
146  s->bit_rate = 8 * (DSS_FRAME_SIZE - 1) * st->codecpar->sample_rate
147  * 512 / (506 * 264);
148  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
150  st->codecpar->sample_rate = 8000;
151  } else {
152  avpriv_request_sample(s, "Support for codec %x in DSS",
153  ctx->audio_codec);
154  return AVERROR_PATCHWELCOME;
155  }
156 
159  st->codecpar->channels = 1;
160 
161  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
162  st->start_time = 0;
163 
164  /* Jump over header */
165 
166  if (avio_seek(pb, ctx->dss_header_size, SEEK_SET) != ctx->dss_header_size)
167  return AVERROR(EIO);
168 
169  ctx->counter = 0;
170  ctx->swap = 0;
171 
172  return 0;
173 }
174 
176 {
177  DSSDemuxContext *ctx = s->priv_data;
178  AVIOContext *pb = s->pb;
179 
182 }
183 
184 static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *data)
185 {
186  int i;
187 
188  if (ctx->swap) {
189  for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
190  data[i] = data[i + 4];
191 
192  /* Zero the padding. */
193  data[DSS_FRAME_SIZE] = 0;
194  data[1] = ctx->dss_sp_swap_byte;
195  } else {
196  ctx->dss_sp_swap_byte = data[DSS_FRAME_SIZE - 2];
197  }
198 
199  /* make sure byte 40 is always 0 */
200  data[DSS_FRAME_SIZE - 2] = 0;
201  ctx->swap ^= 1;
202 }
203 
205 {
206  DSSDemuxContext *ctx = s->priv_data;
207  int read_size, ret, offset = 0, buff_offset = 0;
208  int64_t pos = avio_tell(s->pb);
209 
210  if (ctx->counter == 0)
212 
213  if (ctx->swap) {
214  read_size = DSS_FRAME_SIZE - 2;
215  buff_offset = 3;
216  } else
217  read_size = DSS_FRAME_SIZE;
218 
220  if (ret < 0)
221  return ret;
222 
223  pkt->duration = 264;
224  pkt->pos = pos;
225  pkt->stream_index = 0;
226 
227  if (ctx->counter < read_size) {
228  ret = avio_read(s->pb, pkt->data + buff_offset,
229  ctx->counter);
230  if (ret < ctx->counter)
231  goto error_eof;
232 
233  offset = ctx->counter;
235  }
236  ctx->counter -= read_size;
237 
238  /* This will write one byte into pkt's padding if buff_offset == 3 */
239  ret = avio_read(s->pb, pkt->data + offset + buff_offset,
240  read_size - offset);
241  if (ret < read_size - offset)
242  goto error_eof;
243 
245 
246  if (ctx->dss_sp_swap_byte < 0) {
247  return AVERROR(EAGAIN);
248  }
249 
250  return 0;
251 
252 error_eof:
253  return ret < 0 ? ret : AVERROR_EOF;
254 }
255 
257 {
258  DSSDemuxContext *ctx = s->priv_data;
259  AVStream *st = s->streams[0];
260  int size, byte, ret, offset;
261  int64_t pos = avio_tell(s->pb);
262 
263  if (ctx->counter == 0)
265 
266  /* We make one byte-step here. Don't forget to add offset. */
267  byte = avio_r8(s->pb);
268  if (byte == 0xff)
269  return AVERROR_INVALIDDATA;
270 
271  size = frame_size[byte & 3];
272 
273  ctx->packet_size = size;
274  ctx->counter--;
275 
277  if (ret < 0)
278  return ret;
279  pkt->pos = pos;
280 
281  pkt->data[0] = byte;
282  offset = 1;
283  pkt->duration = 240;
284  s->bit_rate = 8LL * size-- * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
285 
286  pkt->stream_index = 0;
287 
288  if (ctx->counter < size) {
289  ret = avio_read(s->pb, pkt->data + offset,
290  ctx->counter);
291  if (ret < ctx->counter)
292  return ret < 0 ? ret : AVERROR_EOF;
293 
294  offset += ctx->counter;
295  size -= ctx->counter;
296  ctx->counter = 0;
298  }
299  ctx->counter -= size;
300 
301  ret = avio_read(s->pb, pkt->data + offset, size);
302  if (ret < size)
303  return ret < 0 ? ret : AVERROR_EOF;
304 
305  return 0;
306 }
307 
309 {
310  DSSDemuxContext *ctx = s->priv_data;
311 
313  return dss_sp_read_packet(s, pkt);
314  else
315  return dss_723_1_read_packet(s, pkt);
316 }
317 
318 static int dss_read_seek(AVFormatContext *s, int stream_index,
319  int64_t timestamp, int flags)
320 {
321  DSSDemuxContext *ctx = s->priv_data;
322  int64_t ret, seekto;
324  int offset;
325 
327  seekto = timestamp / 264 * 41 / 506 * 512;
328  else
329  seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
330 
331  if (seekto < 0)
332  seekto = 0;
333 
334  seekto += ctx->dss_header_size;
335 
336  ret = avio_seek(s->pb, seekto, SEEK_SET);
337  if (ret < 0)
338  return ret;
339 
341  ctx->swap = !!(header[0] & 0x80);
342  offset = 2*header[1] + 2*ctx->swap;
344  return AVERROR_INVALIDDATA;
346  ctx->counter = 0;
348  } else {
349  ctx->counter = DSS_BLOCK_SIZE - offset;
351  }
352  ctx->dss_sp_swap_byte = -1;
353  return 0;
354 }
355 
356 
358  .name = "dss",
359  .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
360  .priv_data_size = sizeof(DSSDemuxContext),
365  .extensions = "dss"
366 };
DSSDemuxContext::audio_codec
unsigned int audio_codec
Definition: dss.c:49
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: utils.c:4375
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
DSS_HEAD_OFFSET_COMMENT
#define DSS_HEAD_OFFSET_COMMENT
Definition: dss.c:39
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:90
AVPacket::data
uint8_t * data
Definition: packet.h:373
data
const char data[16]
Definition: mxf.c:143
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:391
dss_skip_audio_header
static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:175
dss_723_1_read_packet
static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:256
DSS_HEAD_OFFSET_ACODEC
#define DSS_HEAD_OFFSET_ACODEC
Definition: dss.c:35
dss_sp_byte_swap
static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *data)
Definition: dss.c:184
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
AVCodecParameters::channels
int channels
Audio only.
Definition: codec_par.h:166
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:149
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:538
DSS_ACODEC_DSS_SP
#define DSS_ACODEC_DSS_SP
Definition: dss.c:36
AV_DICT_DONT_STRDUP_VAL
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that's been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:72
dss_read_seek
static int dss_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dss.c:318
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:626
DSS_FRAME_SIZE
#define DSS_FRAME_SIZE
Definition: dss.c:44
DSS_AUTHOR_SIZE
#define DSS_AUTHOR_SIZE
Definition: dss.c:29
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:257
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:94
DSS_HEAD_OFFSET_AUTHOR
#define DSS_HEAD_OFFSET_AUTHOR
Definition: dss.c:28
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:631
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
dss_read_metadata_date
static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset, const char *key)
Definition: dss.c:67
ctx
AVFormatContext * ctx
Definition: movenc.c:48
DSS_BLOCK_SIZE
#define DSS_BLOCK_SIZE
Definition: dss.c:42
DSS_COMMENT_SIZE
#define DSS_COMMENT_SIZE
Definition: dss.c:40
key
const char * key
Definition: hwcontext_opencl.c:168
dss_sp_read_packet
static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:204
AVFormatContext
Format I/O context.
Definition: avformat.h:1107
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:994
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:527
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
read_probe
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
frame_size
static const uint8_t frame_size[4]
Definition: dss.c:46
AV_CODEC_ID_G723_1
@ AV_CODEC_ID_G723_1
Definition: codec_id.h:474
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
AVFormatContext::audio_codec
const AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1589
DSSDemuxContext::counter
int counter
Definition: dss.c:50
DSSDemuxContext
Definition: dss.c:48
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:170
DSS_ACODEC_G723_1
#define DSS_ACODEC_G723_1
Definition: dss.c:37
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
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:116
byte
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 byte
Definition: bytestream.h:99
avpriv_set_pts_info
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:4800
DSSDemuxContext::packet_size
int packet_size
Definition: dss.c:54
size
int size
Definition: twinvq_data.h:10344
DSSDemuxContext::dss_sp_swap_byte
int dss_sp_swap_byte
Definition: dss.c:52
header
static const uint8_t header[24]
Definition: sdr2.c:67
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:607
offset
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
Definition: writing_filters.txt:86
DSS_HEAD_OFFSET_END_TIME
#define DSS_HEAD_OFFSET_END_TIME
Definition: dss.c:32
version
version
Definition: libkvazaar.c:307
DSS_TIME_SIZE
#define DSS_TIME_SIZE
Definition: dss.c:33
i
int i
Definition: input.c:406
dss_read_metadata_string
static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset, unsigned int size, const char *key)
Definition: dss.c:90
ff_dss_demuxer
const AVInputFormat ff_dss_demuxer
Definition: dss.c:357
value
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 default value
Definition: writing_filters.txt:86
AV_CODEC_ID_DSS_SP
@ AV_CODEC_ID_DSS_SP
Definition: codec_id.h:488
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:243
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
AVStream
Stream structure.
Definition: avformat.h:847
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:243
dss_read_packet
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:308
pos
unsigned int pos
Definition: spdifenc.c:412
avformat.h
DSS_AUDIO_BLOCK_HEADER_SIZE
#define DSS_AUDIO_BLOCK_HEADER_SIZE
Definition: dss.c:43
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
channel_layout.h
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:616
AVPacket::stream_index
int stream_index
Definition: packet.h:375
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:327
AVFormatContext::packet_size
unsigned int packet_size
Definition: avformat.h:1218
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
av_free
#define av_free(p)
Definition: tableprint_vlc.h:34
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
AVPacket
This structure stores compressed data.
Definition: packet.h:350
av_dict_set
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:393
AVCodecParameters::channel_layout
uint64_t channel_layout
Audio only.
Definition: codec_par.h:162
dss_read_header
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:112
d
d
Definition: ffmpeg_filter.c:156
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
DSSDemuxContext::swap
int swap
Definition: dss.c:51
dss_probe
static int dss_probe(const AVProbeData *p)
Definition: dss.c:58
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
h
h
Definition: vp9dsp_template.c:2038
AVStream::start_time
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base.
Definition: avformat.h:880
DSSDemuxContext::dss_header_size
int dss_header_size
Definition: dss.c:55
snprintf
#define snprintf
Definition: snprintf.h:34