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  int8_t *dss_sp_buf;
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  ret = ret < 0 ? ret : AVERROR_EOF;
107  goto exit;
108  }
109 
110  ret = av_dict_set(&s->metadata, key, value, 0);
111 
112 exit:
113  av_free(value);
114  return ret;
115 }
116 
118 {
120  AVIOContext *pb = s->pb;
121  AVStream *st;
122  int ret, version;
123 
124  st = avformat_new_stream(s, NULL);
125  if (!st)
126  return AVERROR(ENOMEM);
127 
128  version = avio_r8(pb);
129  ctx->dss_header_size = version * DSS_BLOCK_SIZE;
130 
132  DSS_AUTHOR_SIZE, "author");
133  if (ret)
134  return ret;
135 
137  if (ret)
138  return ret;
139 
141  DSS_COMMENT_SIZE, "comment");
142  if (ret)
143  return ret;
144 
145  avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
146  ctx->audio_codec = avio_r8(pb);
147 
148  if (ctx->audio_codec == DSS_ACODEC_DSS_SP) {
150  st->codecpar->sample_rate = 11025;
151  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
153  st->codecpar->sample_rate = 8000;
154  } else {
155  avpriv_request_sample(s, "Support for codec %x in DSS",
156  ctx->audio_codec);
157  return AVERROR_PATCHWELCOME;
158  }
159 
162  st->codecpar->channels = 1;
163 
164  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
165  st->start_time = 0;
166 
167  /* Jump over header */
168 
169  if (avio_seek(pb, ctx->dss_header_size, SEEK_SET) != ctx->dss_header_size)
170  return AVERROR(EIO);
171 
172  ctx->counter = 0;
173  ctx->swap = 0;
174 
175  ctx->dss_sp_buf = av_malloc(DSS_FRAME_SIZE + 1);
176  if (!ctx->dss_sp_buf)
177  return AVERROR(ENOMEM);
178 
179  return 0;
180 }
181 
183 {
185  AVIOContext *pb = s->pb;
186 
189 }
190 
192  uint8_t *dst, const uint8_t *src)
193 {
194  int i;
195 
196  if (ctx->swap) {
197  for (i = 3; i < DSS_FRAME_SIZE; i += 2)
198  dst[i] = src[i];
199 
200  for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
201  dst[i] = src[i + 4];
202 
203  dst[1] = ctx->dss_sp_swap_byte;
204  } else {
205  memcpy(dst, src, DSS_FRAME_SIZE);
206  ctx->dss_sp_swap_byte = src[DSS_FRAME_SIZE - 2];
207  }
208 
209  /* make sure byte 40 is always 0 */
210  dst[DSS_FRAME_SIZE - 2] = 0;
211  ctx->swap ^= 1;
212 }
213 
215 {
217  AVStream *st = s->streams[0];
218  int read_size, ret, offset = 0, buff_offset = 0;
219  int64_t pos = avio_tell(s->pb);
220 
221  if (ctx->counter == 0)
222  dss_skip_audio_header(s, pkt);
223 
224  if (ctx->swap) {
225  read_size = DSS_FRAME_SIZE - 2;
226  buff_offset = 3;
227  } else
228  read_size = DSS_FRAME_SIZE;
229 
230  ctx->counter -= read_size;
231  ctx->packet_size = DSS_FRAME_SIZE - 1;
232 
233  ret = av_new_packet(pkt, DSS_FRAME_SIZE);
234  if (ret < 0)
235  return ret;
236 
237  pkt->duration = 264;
238  pkt->pos = pos;
239  pkt->stream_index = 0;
240  s->bit_rate = 8LL * ctx->packet_size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
241 
242  if (ctx->counter < 0) {
243  int size2 = ctx->counter + read_size;
244 
245  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
246  size2 - offset);
247  if (ret < size2 - offset)
248  goto error_eof;
249 
250  dss_skip_audio_header(s, pkt);
251  offset = size2;
252  }
253 
254  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
255  read_size - offset);
256  if (ret < read_size - offset)
257  goto error_eof;
258 
259  dss_sp_byte_swap(ctx, pkt->data, ctx->dss_sp_buf);
260 
261  if (ctx->dss_sp_swap_byte < 0) {
262  ret = AVERROR(EAGAIN);
263  goto error_eof;
264  }
265 
266  return pkt->size;
267 
268 error_eof:
269  av_packet_unref(pkt);
270  return ret < 0 ? ret : AVERROR_EOF;
271 }
272 
274 {
276  AVStream *st = s->streams[0];
277  int size, byte, ret, offset;
278  int64_t pos = avio_tell(s->pb);
279 
280  if (ctx->counter == 0)
281  dss_skip_audio_header(s, pkt);
282 
283  /* We make one byte-step here. Don't forget to add offset. */
284  byte = avio_r8(s->pb);
285  if (byte == 0xff)
286  return AVERROR_INVALIDDATA;
287 
288  size = frame_size[byte & 3];
289 
290  ctx->packet_size = size;
291  ctx->counter -= size;
292 
293  ret = av_new_packet(pkt, size);
294  if (ret < 0)
295  return ret;
296  pkt->pos = pos;
297 
298  pkt->data[0] = byte;
299  offset = 1;
300  pkt->duration = 240;
301  s->bit_rate = 8LL * size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
302 
303  pkt->stream_index = 0;
304 
305  if (ctx->counter < 0) {
306  int size2 = ctx->counter + size;
307 
308  ret = avio_read(s->pb, pkt->data + offset,
309  size2 - offset);
310  if (ret < size2 - offset) {
311  av_packet_unref(pkt);
312  return ret < 0 ? ret : AVERROR_EOF;
313  }
314 
315  dss_skip_audio_header(s, pkt);
316  offset = size2;
317  }
318 
319  ret = avio_read(s->pb, pkt->data + offset, size - offset);
320  if (ret < size - offset) {
321  av_packet_unref(pkt);
322  return ret < 0 ? ret : AVERROR_EOF;
323  }
324 
325  return pkt->size;
326 }
327 
329 {
331 
332  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
333  return dss_sp_read_packet(s, pkt);
334  else
335  return dss_723_1_read_packet(s, pkt);
336 }
337 
339 {
341 
342  av_freep(&ctx->dss_sp_buf);
343 
344  return 0;
345 }
346 
347 static int dss_read_seek(AVFormatContext *s, int stream_index,
348  int64_t timestamp, int flags)
349 {
351  int64_t ret, seekto;
353  int offset;
354 
355  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
356  seekto = timestamp / 264 * 41 / 506 * 512;
357  else
358  seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
359 
360  if (seekto < 0)
361  seekto = 0;
362 
363  seekto += ctx->dss_header_size;
364 
365  ret = avio_seek(s->pb, seekto, SEEK_SET);
366  if (ret < 0)
367  return ret;
368 
370  ctx->swap = !!(header[0] & 0x80);
371  offset = 2*header[1] + 2*ctx->swap;
372  if (offset < DSS_AUDIO_BLOCK_HEADER_SIZE)
373  return AVERROR_INVALIDDATA;
374  if (offset == DSS_AUDIO_BLOCK_HEADER_SIZE) {
375  ctx->counter = 0;
377  } else {
378  ctx->counter = DSS_BLOCK_SIZE - offset;
379  offset = avio_skip(s->pb, offset - DSS_AUDIO_BLOCK_HEADER_SIZE);
380  }
381  ctx->dss_sp_swap_byte = -1;
382  return 0;
383 }
384 
385 
387  .name = "dss",
388  .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
389  .priv_data_size = sizeof(DSSDemuxContext),
395  .extensions = "dss"
396 };
#define NULL
Definition: coverity.c:32
Bytestream IO Context.
Definition: avio.h:161
#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
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:4929
#define avpriv_request_sample(...)
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:153
AVInputFormat ff_dss_demuxer
Definition: dss.c:386
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
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1480
#define DSS_AUDIO_BLOCK_HEADER_SIZE
Definition: dss.c:43
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:334
const char * key
int version
Definition: avisynth_c.h:858
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:236
static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:182
static AVPacket pkt
#define src
Definition: vp8dsp.c:254
Format I/O context.
Definition: avformat.h:1358
#define DSS_HEAD_OFFSET_AUTHOR
Definition: dss.c:28
static int dss_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dss.c:347
uint8_t
#define av_malloc(s)
static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:273
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
#define DSS_BLOCK_SIZE
Definition: dss.c:42
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1498
static int dss_read_close(AVFormatContext *s)
Definition: dss.c:338
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
AVStream * avformat_new_stream(AVFormatContext *s, const AVCodec *c)
Add a new stream to a media file.
Definition: utils.c:4502
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:117
uint8_t * data
Definition: avcodec.h:1480
#define AVERROR_EOF
End of file.
Definition: error.h:55
static av_cold int read_close(AVFormatContext *ctx)
Definition: libcdio.c:145
int8_t * dss_sp_buf
Definition: dss.c:53
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
static const uint8_t header[24]
Definition: sdr2.c:67
uint64_t channel_layout
Audio only.
Definition: avcodec.h:4070
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:650
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
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1598
#define DSS_AUTHOR_SIZE
Definition: dss.c:29
#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:3964
static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:214
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:328
int counter
Definition: dss.c:50
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:641
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:448
audio channel layout utility functions
#define DSS_HEAD_OFFSET_END_TIME
Definition: dss.c:32
#define DSS_COMMENT_SIZE
Definition: dss.c:40
static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *dst, const uint8_t *src)
Definition: dss.c:191
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
#define DSS_HEAD_OFFSET_COMMENT
Definition: dss.c:39
static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset, unsigned int size, const char *key)
Definition: dss.c:91
#define DSS_TIME_SIZE
Definition: dss.c:33
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
Stream structure.
Definition: avformat.h:881
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:62
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 byte
Definition: bytestream.h:87
AVIOContext * pb
I/O context.
Definition: avformat.h:1400
#define DSS_HEAD_OFFSET_ACODEC
Definition: dss.c:35
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
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
static const uint8_t frame_size[4]
Definition: dss.c:46
#define snprintf
Definition: snprintf.h:34
int packet_size
Definition: dss.c:55
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int swap
Definition: dss.c:51
#define flags(name, subs,...)
Definition: cbs_av1.c:561
int dss_sp_swap_byte
Definition: dss.c:52
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int sample_rate
Audio only.
Definition: avcodec.h:4078
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
#define DSS_FRAME_SIZE
Definition: dss.c:44
#define DSS_ACODEC_G723_1
Definition: dss.c:37
int64_t start_time
Decoding: pts of the first frame of the stream in presentation order, in stream time base...
Definition: avformat.h:920
static int dss_probe(const AVProbeData *p)
Definition: dss.c:59
#define DSS_ACODEC_DSS_SP
Definition: dss.c:36
#define av_free(p)
int dss_header_size
Definition: dss.c:56
void * priv_data
Format private data.
Definition: avformat.h:1386
static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset, const char *key)
Definition: dss.c:68
int channels
Audio only.
Definition: avcodec.h:4074
#define av_freep(p)
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:654
unsigned int audio_codec
Definition: dss.c:49
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1482
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 AV_CH_LAYOUT_MONO
#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:1457