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 
22 #include "libavutil/attributes.h"
23 #include "libavutil/bswap.h"
25 #include "libavutil/intreadwrite.h"
26 
27 #include "avformat.h"
28 #include "internal.h"
29 
30 #define DSS_HEAD_OFFSET_AUTHOR 0xc
31 #define DSS_AUTHOR_SIZE 16
32 
33 #define DSS_HEAD_OFFSET_START_TIME 0x26
34 #define DSS_HEAD_OFFSET_END_TIME 0x32
35 #define DSS_TIME_SIZE 12
36 
37 #define DSS_HEAD_OFFSET_ACODEC 0x2a4
38 #define DSS_ACODEC_DSS_SP 0x0 /* SP mode */
39 #define DSS_ACODEC_G723_1 0x2 /* LP mode */
40 
41 #define DSS_HEAD_OFFSET_COMMENT 0x31e
42 #define DSS_COMMENT_SIZE 64
43 
44 #define DSS_BLOCK_SIZE 512
45 #define DSS_AUDIO_BLOCK_HEADER_SIZE 6
46 #define DSS_FRAME_SIZE 42
47 
48 static const uint8_t frame_size[4] = { 24, 20, 4, 1 };
49 
50 typedef struct DSSDemuxContext {
51  unsigned int audio_codec;
52  int counter;
53  int swap;
55  int8_t *dss_sp_buf;
56 
60 
61 static int dss_probe(const AVProbeData *p)
62 {
63  if ( AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')
64  && AV_RL32(p->buf) != MKTAG(0x3, 'd', 's', 's'))
65  return 0;
66 
67  return AVPROBE_SCORE_MAX;
68 }
69 
70 static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
71  const char *key)
72 {
73  AVIOContext *pb = s->pb;
74  char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 };
75  int y, month, d, h, minute, sec;
76  int ret;
77 
78  avio_seek(pb, offset, SEEK_SET);
79 
80  ret = avio_read(s->pb, string, DSS_TIME_SIZE);
81  if (ret < DSS_TIME_SIZE)
82  return ret < 0 ? ret : AVERROR_EOF;
83 
84  if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6)
85  return AVERROR_INVALIDDATA;
86  /* We deal with a two-digit year here, so set the default date to 2000
87  * and hope it will never be used in the next century. */
88  snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
89  y + 2000, month, d, h, minute, sec);
90  return av_dict_set(&s->metadata, key, datetime, 0);
91 }
92 
94  unsigned int size, const char *key)
95 {
96  AVIOContext *pb = s->pb;
97  char *value;
98  int ret;
99 
100  avio_seek(pb, offset, SEEK_SET);
101 
102  value = av_mallocz(size + 1);
103  if (!value)
104  return AVERROR(ENOMEM);
105 
106  ret = avio_read(s->pb, value, size);
107  if (ret < size) {
108  ret = ret < 0 ? ret : AVERROR_EOF;
109  goto exit;
110  }
111 
112  ret = av_dict_set(&s->metadata, key, value, 0);
113 
114 exit:
115  av_free(value);
116  return ret;
117 }
118 
120 {
122  AVIOContext *pb = s->pb;
123  AVStream *st;
124  int ret, version;
125 
126  st = avformat_new_stream(s, NULL);
127  if (!st)
128  return AVERROR(ENOMEM);
129 
130  version = avio_r8(pb);
131  ctx->dss_header_size = version * DSS_BLOCK_SIZE;
132 
134  DSS_AUTHOR_SIZE, "author");
135  if (ret)
136  return ret;
137 
139  if (ret)
140  return ret;
141 
143  DSS_COMMENT_SIZE, "comment");
144  if (ret)
145  return ret;
146 
147  avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
148  ctx->audio_codec = avio_r8(pb);
149 
150  if (ctx->audio_codec == DSS_ACODEC_DSS_SP) {
152  st->codecpar->sample_rate = 11025;
153  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
155  st->codecpar->sample_rate = 8000;
156  } else {
157  avpriv_request_sample(s, "Support for codec %x in DSS",
158  ctx->audio_codec);
159  return AVERROR_PATCHWELCOME;
160  }
161 
164  st->codecpar->channels = 1;
165 
166  avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
167  st->start_time = 0;
168 
169  /* Jump over header */
170 
171  if (avio_seek(pb, ctx->dss_header_size, SEEK_SET) != ctx->dss_header_size)
172  return AVERROR(EIO);
173 
174  ctx->counter = 0;
175  ctx->swap = 0;
176 
177  ctx->dss_sp_buf = av_malloc(DSS_FRAME_SIZE + 1);
178  if (!ctx->dss_sp_buf)
179  return AVERROR(ENOMEM);
180 
181  return 0;
182 }
183 
185 {
187  AVIOContext *pb = s->pb;
188 
191 }
192 
194  uint8_t *dst, const uint8_t *src)
195 {
196  int i;
197 
198  if (ctx->swap) {
199  for (i = 3; i < DSS_FRAME_SIZE; i += 2)
200  dst[i] = src[i];
201 
202  for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
203  dst[i] = src[i + 4];
204 
205  dst[1] = ctx->dss_sp_swap_byte;
206  } else {
207  memcpy(dst, src, DSS_FRAME_SIZE);
208  ctx->dss_sp_swap_byte = src[DSS_FRAME_SIZE - 2];
209  }
210 
211  /* make sure byte 40 is always 0 */
212  dst[DSS_FRAME_SIZE - 2] = 0;
213  ctx->swap ^= 1;
214 }
215 
217 {
219  AVStream *st = s->streams[0];
220  int read_size, ret, offset = 0, buff_offset = 0;
221  int64_t pos = avio_tell(s->pb);
222 
223  if (ctx->counter == 0)
224  dss_skip_audio_header(s, pkt);
225 
226  if (ctx->swap) {
227  read_size = DSS_FRAME_SIZE - 2;
228  buff_offset = 3;
229  } else
230  read_size = DSS_FRAME_SIZE;
231 
232  ctx->counter -= read_size;
233  ctx->packet_size = DSS_FRAME_SIZE - 1;
234 
235  ret = av_new_packet(pkt, DSS_FRAME_SIZE);
236  if (ret < 0)
237  return ret;
238 
239  pkt->duration = 264;
240  pkt->pos = pos;
241  pkt->stream_index = 0;
242  s->bit_rate = 8LL * ctx->packet_size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
243 
244  if (ctx->counter < 0) {
245  int size2 = ctx->counter + read_size;
246 
247  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
248  size2 - offset);
249  if (ret < size2 - offset)
250  goto error_eof;
251 
252  dss_skip_audio_header(s, pkt);
253  offset = size2;
254  }
255 
256  ret = avio_read(s->pb, ctx->dss_sp_buf + offset + buff_offset,
257  read_size - offset);
258  if (ret < read_size - offset)
259  goto error_eof;
260 
261  dss_sp_byte_swap(ctx, pkt->data, ctx->dss_sp_buf);
262 
263  if (ctx->dss_sp_swap_byte < 0) {
264  ret = AVERROR(EAGAIN);
265  goto error_eof;
266  }
267 
268  return pkt->size;
269 
270 error_eof:
271  av_packet_unref(pkt);
272  return ret < 0 ? ret : AVERROR_EOF;
273 }
274 
276 {
278  AVStream *st = s->streams[0];
279  int size, byte, ret, offset;
280  int64_t pos = avio_tell(s->pb);
281 
282  if (ctx->counter == 0)
283  dss_skip_audio_header(s, pkt);
284 
285  /* We make one byte-step here. Don't forget to add offset. */
286  byte = avio_r8(s->pb);
287  if (byte == 0xff)
288  return AVERROR_INVALIDDATA;
289 
290  size = frame_size[byte & 3];
291 
292  ctx->packet_size = size;
293  ctx->counter -= size;
294 
295  ret = av_new_packet(pkt, size);
296  if (ret < 0)
297  return ret;
298  pkt->pos = pos;
299 
300  pkt->data[0] = byte;
301  offset = 1;
302  pkt->duration = 240;
303  s->bit_rate = 8LL * size * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
304 
305  pkt->stream_index = 0;
306 
307  if (ctx->counter < 0) {
308  int size2 = ctx->counter + size;
309 
310  ret = avio_read(s->pb, pkt->data + offset,
311  size2 - offset);
312  if (ret < size2 - offset) {
313  av_packet_unref(pkt);
314  return ret < 0 ? ret : AVERROR_EOF;
315  }
316 
317  dss_skip_audio_header(s, pkt);
318  offset = size2;
319  }
320 
321  ret = avio_read(s->pb, pkt->data + offset, size - offset);
322  if (ret < size - offset) {
323  av_packet_unref(pkt);
324  return ret < 0 ? ret : AVERROR_EOF;
325  }
326 
327  return pkt->size;
328 }
329 
331 {
333 
334  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
335  return dss_sp_read_packet(s, pkt);
336  else
337  return dss_723_1_read_packet(s, pkt);
338 }
339 
341 {
343 
344  av_freep(&ctx->dss_sp_buf);
345 
346  return 0;
347 }
348 
349 static int dss_read_seek(AVFormatContext *s, int stream_index,
350  int64_t timestamp, int flags)
351 {
353  int64_t ret, seekto;
355  int offset;
356 
357  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
358  seekto = timestamp / 264 * 41 / 506 * 512;
359  else
360  seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
361 
362  if (seekto < 0)
363  seekto = 0;
364 
365  seekto += ctx->dss_header_size;
366 
367  ret = avio_seek(s->pb, seekto, SEEK_SET);
368  if (ret < 0)
369  return ret;
370 
372  ctx->swap = !!(header[0] & 0x80);
373  offset = 2*header[1] + 2*ctx->swap;
374  if (offset < DSS_AUDIO_BLOCK_HEADER_SIZE)
375  return AVERROR_INVALIDDATA;
376  if (offset == DSS_AUDIO_BLOCK_HEADER_SIZE) {
377  ctx->counter = 0;
379  } else {
380  ctx->counter = DSS_BLOCK_SIZE - offset;
381  offset = avio_skip(s->pb, offset - DSS_AUDIO_BLOCK_HEADER_SIZE);
382  }
383  ctx->dss_sp_swap_byte = -1;
384  return 0;
385 }
386 
387 
389  .name = "dss",
390  .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
391  .priv_data_size = sizeof(DSSDemuxContext),
397  .extensions = "dss"
398 };
#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:1497
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:4892
#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:388
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: avcodec.h:3957
int size
Definition: avcodec.h:1478
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:45
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:184
static AVPacket pkt
#define src
Definition: vp8dsp.c:254
Macro definitions for various function/variable attributes.
Format I/O context.
Definition: avformat.h:1358
#define DSS_HEAD_OFFSET_AUTHOR
Definition: dss.c:30
static int dss_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dss.c:349
uint8_t
#define av_malloc(s)
static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:275
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:44
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: avcodec.h:1495
static int dss_read_close(AVFormatContext *s)
Definition: dss.c:340
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:4465
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:119
uint8_t * data
Definition: avcodec.h:1477
#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:55
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:4059
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:31
#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:3953
static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:216
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:330
int counter
Definition: dss.c:52
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:34
#define DSS_COMMENT_SIZE
Definition: dss.c:42
static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *dst, const uint8_t *src)
Definition: dss.c:193
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
#define DSS_HEAD_OFFSET_COMMENT
Definition: dss.c:41
static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset, unsigned int size, const char *key)
Definition: dss.c:93
#define DSS_TIME_SIZE
Definition: dss.c:35
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:37
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
byte swapping routines
static const uint8_t frame_size[4]
Definition: dss.c:48
#define snprintf
Definition: snprintf.h:34
int packet_size
Definition: dss.c:57
This structure contains the data a format has to probe a file.
Definition: avformat.h:446
int swap
Definition: dss.c:53
#define flags(name, subs,...)
Definition: cbs_av1.c:561
int dss_sp_swap_byte
Definition: dss.c:54
static int read_probe(const AVProbeData *pd)
Definition: jvdec.c:55
int sample_rate
Audio only.
Definition: avcodec.h:4067
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:458
Main libavformat public API header.
#define DSS_FRAME_SIZE
Definition: dss.c:46
#define DSS_ACODEC_G723_1
Definition: dss.c:39
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:61
#define DSS_ACODEC_DSS_SP
Definition: dss.c:38
#define av_free(p)
int dss_header_size
Definition: dss.c:58
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:70
int channels
Audio only.
Definition: avcodec.h:4063
#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:51
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1028
int stream_index
Definition: avcodec.h:1479
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:1454