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;
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 {
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 
144  if (ctx->audio_codec == DSS_ACODEC_DSS_SP) {
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 {
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 {
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)
214  dss_skip_audio_header(s, pkt);
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;
223  ctx->packet_size = DSS_FRAME_SIZE - 1;
224 
225  ret = av_new_packet(pkt, DSS_FRAME_SIZE);
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 
242  dss_skip_audio_header(s, pkt);
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 {
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)
271  dss_skip_audio_header(s, pkt);
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 
283  ret = av_new_packet(pkt, size);
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 
304  dss_skip_audio_header(s, pkt);
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 {
319 
320  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
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 {
330  int64_t ret, seekto;
332  int offset;
333 
334  if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
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;
351  if (offset < DSS_AUDIO_BLOCK_HEADER_SIZE)
352  return AVERROR_INVALIDDATA;
353  if (offset == DSS_AUDIO_BLOCK_HEADER_SIZE) {
354  ctx->counter = 0;
356  } else {
357  ctx->counter = DSS_BLOCK_SIZE - offset;
358  offset = avio_skip(s->pb, offset - DSS_AUDIO_BLOCK_HEADER_SIZE);
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 };
int8_t dss_sp_buf[DSS_FRAME_SIZE+1]
Definition: dss.c:53
#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
version
Definition: libkvazaar.c:287
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:383
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:4938
#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:365
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:60
int size
Definition: packet.h:364
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:253
int64_t bit_rate
Total stream bitrate in bit/s, 0 if not available.
Definition: avformat.h:1473
#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:341
const char * key
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
static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:174
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1351
#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:326
uint8_t
static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:263
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: packet.h:381
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:4519
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1419
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:113
uint8_t * data
Definition: packet.h:363
#define AVERROR_EOF
End of file.
Definition: error.h: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: codec_par.h:162
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:637
#define src
Definition: vp8dsp.c:254
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
AVDictionary * metadata
Metadata that applies to the whole file.
Definition: avformat.h:1591
#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:153
unsigned int pos
Definition: spdifenc.c:410
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:56
static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:206
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:316
int counter
Definition: dss.c:50
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:628
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:443
audio channel layout utility functions
#define DSS_HEAD_OFFSET_END_TIME
Definition: dss.c:32
#define AV_DICT_DONT_STRDUP_VAL
Take ownership of a value that&#39;s been allocated with av_malloc() or another memory allocation functio...
Definition: dict.h:76
#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:183
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:527
Stream structure.
Definition: avformat.h:876
#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:1393
#define DSS_HEAD_OFFSET_ACODEC
Definition: dss.c:35
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:441
int swap
Definition: dss.c:51
#define flags(name, subs,...)
Definition: cbs_av1.c:560
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: codec_par.h:170
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:453
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:915
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:1379
static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset, const char *key)
Definition: dss.c:68
int channels
Audio only.
Definition: codec_par.h:166
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:650
unsigned int audio_codec
Definition: dss.c:49
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1023
int stream_index
Definition: packet.h:365
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:406
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: packet.h:340
int i
Definition: input.c:407