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 "demux.h"
27 #include "internal.h"
28 
29 #define DSS_HEAD_OFFSET_AUTHOR 0xc
30 #define DSS_AUTHOR_SIZE 16
31 
32 #define DSS_HEAD_OFFSET_START_TIME 0x26
33 #define DSS_HEAD_OFFSET_END_TIME 0x32
34 #define DSS_TIME_SIZE 12
35 
36 #define DSS_HEAD_OFFSET_ACODEC 0x2a4
37 #define DSS_ACODEC_DSS_SP 0x0 /* SP mode */
38 #define DSS_ACODEC_G723_1 0x2 /* LP mode */
39 
40 #define DSS_HEAD_OFFSET_COMMENT 0x31e
41 #define DSS_COMMENT_SIZE 64
42 
43 #define DSS_BLOCK_SIZE 512
44 #define DSS_AUDIO_BLOCK_HEADER_SIZE 6
45 #define DSS_FRAME_SIZE 42
46 
47 static const uint8_t frame_size[4] = { 24, 20, 4, 1 };
48 
49 typedef struct DSSDemuxContext {
50  unsigned int audio_codec;
51  int counter;
52  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  s->bit_rate = 8 * (DSS_FRAME_SIZE - 1) * st->codecpar->sample_rate
148  * 512 / (506 * 264);
149  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
151  st->codecpar->sample_rate = 8000;
152  } else {
153  avpriv_request_sample(s, "Support for codec %x in DSS",
154  ctx->audio_codec);
155  return AVERROR_PATCHWELCOME;
156  }
157 
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  .p.name = "dss",
359  .p.long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
360  .p.extensions = "dss",
361  .priv_data_size = sizeof(DSSDemuxContext),
366 };
DSSDemuxContext::audio_codec
unsigned int audio_codec
Definition: dss.c:50
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
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:51
DSS_HEAD_OFFSET_COMMENT
#define DSS_HEAD_OFFSET_COMMENT
Definition: dss.c:40
avformat_new_stream
AVStream * avformat_new_stream(AVFormatContext *s, const struct AVCodec *c)
Add a new stream to a media file.
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVPacket::data
uint8_t * data
Definition: packet.h:522
data
const char data[16]
Definition: mxf.c:148
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:540
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:36
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:463
avpriv_set_pts_info
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits, unsigned int pts_num, unsigned int pts_den)
Set the time base and wrapping info for a given stream.
Definition: avformat.c:853
read_seek
static int read_seek(AVFormatContext *ctx, int stream_index, int64_t timestamp, int flags)
Definition: libcdio.c:151
avio_tell
static av_always_inline int64_t avio_tell(AVIOContext *s)
ftell() equivalent for AVIOContext.
Definition: avio.h:494
DSS_ACODEC_DSS_SP
#define DSS_ACODEC_DSS_SP
Definition: dss.c:37
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:79
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
DSS_FRAME_SIZE
#define DSS_FRAME_SIZE
Definition: dss.c:45
read_packet
static int read_packet(void *opaque, uint8_t *buf, int buf_size)
Definition: avio_read_callback.c:41
DSS_AUTHOR_SIZE
#define DSS_AUTHOR_SIZE
Definition: dss.c:30
intreadwrite.h
s
#define s(width, name)
Definition: cbs_vp9.c:198
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:98
DSS_HEAD_OFFSET_AUTHOR
#define DSS_HEAD_OFFSET_AUTHOR
Definition: dss.c:29
AVInputFormat::name
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:553
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:453
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:43
DSS_COMMENT_SIZE
#define DSS_COMMENT_SIZE
Definition: dss.c:41
key
const char * key
Definition: hwcontext_opencl.c:189
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:1255
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:766
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:550
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
frame_size
static const uint8_t frame_size[4]
Definition: dss.c:47
AV_CODEC_ID_G723_1
@ AV_CODEC_ID_G723_1
Definition: codec_id.h:492
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:451
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:180
DSSDemuxContext::counter
int counter
Definition: dss.c:51
DSSDemuxContext
Definition: dss.c:49
AVCodecParameters::sample_rate
int sample_rate
Audio only.
Definition: codec_par.h:184
AVFormatContext::audio_codec
const struct AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1786
DSS_ACODEC_G723_1
#define DSS_ACODEC_G723_1
Definition: dss.c:38
AVIOContext
Bytestream IO Context.
Definition: avio.h:160
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:106
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
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:303
DSSDemuxContext::packet_size
int packet_size
Definition: dss.c:55
size
int size
Definition: twinvq_data.h:10344
DSSDemuxContext::dss_sp_swap_byte
int dss_sp_swap_byte
Definition: dss.c:53
FFInputFormat::p
AVInputFormat p
The public AVInputFormat.
Definition: demux.h:41
header
static const uint8_t header[24]
Definition: sdr2.c:68
avio_r8
int avio_r8(AVIOContext *s)
Definition: aviobuf.c:602
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:33
version
version
Definition: libkvazaar.c:321
DSS_TIME_SIZE
#define DSS_TIME_SIZE
Definition: dss.c:34
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
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
AV_CODEC_ID_DSS_SP
@ AV_CODEC_ID_DSS_SP
Definition: codec_id.h:506
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:254
demux.h
ret
ret
Definition: filter_design.txt:187
AVStream
Stream structure.
Definition: avformat.h:743
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:230
dss_read_packet
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:308
pos
unsigned int pos
Definition: spdifenc.c:413
avformat.h
DSS_AUDIO_BLOCK_HEADER_SIZE
#define DSS_AUDIO_BLOCK_HEADER_SIZE
Definition: dss.c:44
AV_RL32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:92
channel_layout.h
ff_dss_demuxer
const FFInputFormat ff_dss_demuxer
Definition: dss.c:357
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:611
AVPacket::stream_index
int stream_index
Definition: packet.h:524
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:317
AVFormatContext::packet_size
unsigned int packet_size
Definition: avformat.h:1399
read_probe
static int read_probe(const AVProbeData *p)
Definition: cdg.c:30
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:378
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
AVCodecParameters::codec_id
enum AVCodecID codec_id
Specific type of the encoded data (the codec used).
Definition: codec_par.h:55
AVPacket
This structure stores compressed data.
Definition: packet.h:499
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:88
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:542
FFInputFormat
Definition: demux.h:37
dss_read_header
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:113
d
d
Definition: ffmpeg_filter.c:410
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
DSSDemuxContext::swap
int swap
Definition: dss.c:52
dss_probe
static int dss_probe(const AVProbeData *p)
Definition: dss.c:59
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:792
DSSDemuxContext::dss_header_size
int dss_header_size
Definition: dss.c:56
snprintf
#define snprintf
Definition: snprintf.h:34