FFmpeg
dss.c
Go to the documentation of this file.
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;
54 
58 
59 static int dss_probe(const AVProbeData *p)
60 {
61  if ( AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')
62  && AV_RL32(p->buf) != MKTAG(0x3, 'd', 's', 's'))
63  return 0;
64 
65  return AVPROBE_SCORE_MAX;
66 }
67 
68 static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
69  const char *key)
70 {
71  AVIOContext *pb = s->pb;
72  char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 };
73  int y, month, d, h, minute, sec;
74  int ret;
75 
76  avio_seek(pb, offset, SEEK_SET);
77 
78  ret = avio_read(s->pb, string, DSS_TIME_SIZE);
79  if (ret < DSS_TIME_SIZE)
80  return ret < 0 ? ret : AVERROR_EOF;
81 
82  if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6)
83  return AVERROR_INVALIDDATA;
84  /* We deal with a two-digit year here, so set the default date to 2000
85  * and hope it will never be used in the next century. */
86  snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
87  y + 2000, month, d, h, minute, sec);
88  return av_dict_set(&s->metadata, key, datetime, 0);
89 }
90 
92  unsigned int size, const char *key)
93 {
94  AVIOContext *pb = s->pb;
95  char *value;
96  int ret;
97 
98  avio_seek(pb, offset, SEEK_SET);
99 
100  value = av_mallocz(size + 1);
101  if (!value)
102  return AVERROR(ENOMEM);
103 
104  ret = avio_read(s->pb, value, size);
105  if (ret < size) {
106  av_free(value);
107  return ret < 0 ? ret : AVERROR_EOF;
108  }
109 
110  return av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
111 }
112 
114 {
115  DSSDemuxContext *ctx = s->priv_data;
116  AVIOContext *pb = s->pb;
117  AVStream *st;
118  int ret, version;
119 
120  st = avformat_new_stream(s, NULL);
121  if (!st)
122  return AVERROR(ENOMEM);
123 
124  version = avio_r8(pb);
125  ctx->dss_header_size = version * DSS_BLOCK_SIZE;
126 
128  DSS_AUTHOR_SIZE, "author");
129  if (ret)
130  return ret;
131 
133  if (ret)
134  return ret;
135 
137  DSS_COMMENT_SIZE, "comment");
138  if (ret)
139  return ret;
140 
141  avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
142  ctx->audio_codec = avio_r8(pb);
143 
146  st->codecpar->sample_rate = 11025;
147  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
149  st->codecpar->sample_rate = 8000;
150  } else {
151  avpriv_request_sample(s, "Support for codec %x in DSS",
152  ctx->audio_codec);
153  return AVERROR_PATCHWELCOME;
154  }
155 
158  st->codecpar->channels = 1;
159 
160  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
161  st->start_time = 0;
162 
163  /* Jump over header */
164 
165  if (avio_seek(pb, ctx->dss_header_size, SEEK_SET) != ctx->dss_header_size)
166  return AVERROR(EIO);
167 
168  ctx->counter = 0;
169  ctx->swap = 0;
170 
171  return 0;
172 }
173 
175 {
176  DSSDemuxContext *ctx = s->priv_data;
177  AVIOContext *pb = s->pb;
178 
181 }
182 
184  uint8_t *dst, const uint8_t *src)
185 {
186  int i;
187 
188  if (ctx->swap) {
189  for (i = 3; i < DSS_FRAME_SIZE; i += 2)
190  dst[i] = src[i];
191 
192  for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
193  dst[i] = src[i + 4];
194 
195  dst[1] = ctx->dss_sp_swap_byte;
196  } else {
197  memcpy(dst, src, DSS_FRAME_SIZE);
198  ctx->dss_sp_swap_byte = src[DSS_FRAME_SIZE - 2];
199  }
200 
201  /* make sure byte 40 is always 0 */
202  dst[DSS_FRAME_SIZE - 2] = 0;
203  ctx->swap ^= 1;
204 }
205 
207 {
208  DSSDemuxContext *ctx = s->priv_data;
209  AVStream *st = s->streams[0];
210  int read_size, ret, offset = 0, buff_offset = 0;
211  int64_t pos = avio_tell(s->pb);
212 
213  if (ctx->counter == 0)
215 
216  if (ctx->swap) {
217  read_size = DSS_FRAME_SIZE - 2;
218  buff_offset = 3;
219  } else
220  read_size = DSS_FRAME_SIZE;
221 
222  ctx->counter -= read_size;
224 
226  if (ret < 0)
227  return ret;
228 
229  pkt->duration = 264;
230  pkt->pos = pos;
231  pkt->stream_index = 0;
232  s->bit_rate = 8LL * ctx->packet_size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
233 
234  if (ctx->counter < 0) {
235  int size2 = ctx->counter + read_size;
236 
237  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
238  size2 - offset);
239  if (ret < size2 - offset)
240  goto error_eof;
241 
243  offset = size2;
244  }
245 
246  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
247  read_size - offset);
248  if (ret < read_size - offset)
249  goto error_eof;
250 
251  dss_sp_byte_swap(ctx, pkt->data, ctx->dss_sp_buf);
252 
253  if (ctx->dss_sp_swap_byte < 0) {
254  return AVERROR(EAGAIN);
255  }
256 
257  return pkt->size;
258 
259 error_eof:
260  return ret < 0 ? ret : AVERROR_EOF;
261 }
262 
264 {
265  DSSDemuxContext *ctx = s->priv_data;
266  AVStream *st = s->streams[0];
267  int size, byte, ret, offset;
268  int64_t pos = avio_tell(s->pb);
269 
270  if (ctx->counter == 0)
272 
273  /* We make one byte-step here. Don't forget to add offset. */
274  byte = avio_r8(s->pb);
275  if (byte == 0xff)
276  return AVERROR_INVALIDDATA;
277 
278  size = frame_size[byte & 3];
279 
280  ctx->packet_size = size;
281  ctx->counter -= size;
282 
284  if (ret < 0)
285  return ret;
286  pkt->pos = pos;
287 
288  pkt->data[0] = byte;
289  offset = 1;
290  pkt->duration = 240;
291  s->bit_rate = 8LL * size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
292 
293  pkt->stream_index = 0;
294 
295  if (ctx->counter < 0) {
296  int size2 = ctx->counter + size;
297 
298  ret = avio_read(s->pb, pkt->data + offset,
299  size2 - offset);
300  if (ret < size2 - offset) {
301  return ret < 0 ? ret : AVERROR_EOF;
302  }
303 
305  offset = size2;
306  }
307 
308  ret = avio_read(s->pb, pkt->data + offset, size - offset);
309  if (ret < size - offset) {
310  return ret < 0 ? ret : AVERROR_EOF;
311  }
312 
313  return pkt->size;
314 }
315 
317 {
318  DSSDemuxContext *ctx = s->priv_data;
319 
321  return dss_sp_read_packet(s, pkt);
322  else
323  return dss_723_1_read_packet(s, pkt);
324 }
325 
326 static int dss_read_seek(AVFormatContext *s, int stream_index,
327  int64_t timestamp, int flags)
328 {
329  DSSDemuxContext *ctx = s->priv_data;
330  int64_t ret, seekto;
332  int offset;
333 
335  seekto = timestamp / 264 * 41 / 506 * 512;
336  else
337  seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
338 
339  if (seekto < 0)
340  seekto = 0;
341 
342  seekto += ctx->dss_header_size;
343 
344  ret = avio_seek(s->pb, seekto, SEEK_SET);
345  if (ret < 0)
346  return ret;
347 
349  ctx->swap = !!(header[0] & 0x80);
350  offset = 2*header[1] + 2*ctx->swap;
352  return AVERROR_INVALIDDATA;
354  ctx->counter = 0;
356  } else {
357  ctx->counter = DSS_BLOCK_SIZE - offset;
359  }
360  ctx->dss_sp_swap_byte = -1;
361  return 0;
362 }
363 
364 
366  .name = "dss",
367  .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
368  .priv_data_size = sizeof(DSSDemuxContext),
373  .extensions = "dss"
374 };
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:4526
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:55
MKTAG
#define MKTAG(a, b, c, d)
Definition: common.h:406
AV_CH_LAYOUT_MONO
#define AV_CH_LAYOUT_MONO
Definition: channel_layout.h:85
AVPacket::data
uint8_t * data
Definition: packet.h:355
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:373
dss_skip_audio_header
static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:174
dss_723_1_read_packet
static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:263
DSS_HEAD_OFFSET_ACODEC
#define DSS_HEAD_OFFSET_ACODEC
Definition: dss.c:35
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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:153
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:557
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:74
AVFormatContext::audio_codec
AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1812
dss_read_seek
static int dss_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dss.c:326
AVInputFormat
Definition: avformat.h:636
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:88
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:641
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
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:68
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:206
AVFormatContext
Format I/O context.
Definition: avformat.h:1335
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1012
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:62
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:462
src
#define src
Definition: vp8dsp.c:254
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:441
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
ff_dss_demuxer
AVInputFormat ff_dss_demuxer
Definition: dss.c:365
AVIOContext
Bytestream IO Context.
Definition: avio.h:161
AVPacket::size
int size
Definition: packet.h:356
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:188
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:95
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:4948
DSSDemuxContext::packet_size
int packet_size
Definition: dss.c:55
size
int size
Definition: twinvq_data.h:11134
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:616
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:292
DSS_TIME_SIZE
#define DSS_TIME_SIZE
Definition: dss.c:33
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
dss_read_metadata_string
static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset, unsigned int size, const char *key)
Definition: dss.c:91
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
uint8_t
uint8_t
Definition: audio_convert.c:194
AV_CODEC_ID_DSS_SP
@ AV_CODEC_ID_DSS_SP
Definition: codec_id.h:476
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:237
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:865
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:241
dss_read_packet
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:316
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:88
channel_layout.h
pkt
static AVPacket pkt
Definition: demuxing_decoding.c:54
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:625
AVPacket::stream_index
int stream_index
Definition: packet.h:357
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:329
AVFormatContext::packet_size
unsigned int packet_size
Definition: avformat.h:1459
dss_sp_byte_swap
static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *dst, const uint8_t *src)
Definition: dss.c:183
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:39
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:332
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:375
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:113
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:565
DSSDemuxContext::swap
int swap
Definition: dss.c:51
dss_probe
static int dss_probe(const AVProbeData *p)
Definition: dss.c:59
DSSDemuxContext::dss_sp_buf
int8_t dss_sp_buf[DSS_FRAME_SIZE+1]
Definition: dss.c:53
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
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:904
DSSDemuxContext::dss_header_size
int dss_header_size
Definition: dss.c:56
snprintf
#define snprintf
Definition: snprintf.h:34