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 
57 
58 static int dss_probe(const AVProbeData *p)
59 {
60  if ( AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')
61  && AV_RL32(p->buf) != MKTAG(0x3, 'd', 's', 's'))
62  return 0;
63 
64  return AVPROBE_SCORE_MAX;
65 }
66 
67 static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
68  const char *key)
69 {
70  AVIOContext *pb = s->pb;
71  char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 };
72  int y, month, d, h, minute, sec;
73  int ret;
74 
75  avio_seek(pb, offset, SEEK_SET);
76 
77  ret = avio_read(s->pb, string, DSS_TIME_SIZE);
78  if (ret < DSS_TIME_SIZE)
79  return ret < 0 ? ret : AVERROR_EOF;
80 
81  if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6)
82  return AVERROR_INVALIDDATA;
83  /* We deal with a two-digit year here, so set the default date to 2000
84  * and hope it will never be used in the next century. */
85  snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
86  y + 2000, month, d, h, minute, sec);
87  return av_dict_set(&s->metadata, key, datetime, 0);
88 }
89 
91  unsigned int size, const char *key)
92 {
93  AVIOContext *pb = s->pb;
94  char *value;
95  int ret;
96 
97  avio_seek(pb, offset, SEEK_SET);
98 
99  value = av_mallocz(size + 1);
100  if (!value)
101  return AVERROR(ENOMEM);
102 
103  ret = avio_read(s->pb, value, size);
104  if (ret < size) {
105  av_free(value);
106  return ret < 0 ? ret : AVERROR_EOF;
107  }
108 
109  return av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
110 }
111 
113 {
114  DSSDemuxContext *ctx = s->priv_data;
115  AVIOContext *pb = s->pb;
116  AVStream *st;
117  int ret, version;
118 
119  st = avformat_new_stream(s, NULL);
120  if (!st)
121  return AVERROR(ENOMEM);
122 
123  version = avio_r8(pb);
124  ctx->dss_header_size = version * DSS_BLOCK_SIZE;
125 
127  DSS_AUTHOR_SIZE, "author");
128  if (ret)
129  return ret;
130 
132  if (ret)
133  return ret;
134 
136  DSS_COMMENT_SIZE, "comment");
137  if (ret)
138  return ret;
139 
140  avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
141  ctx->audio_codec = avio_r8(pb);
142 
145  st->codecpar->sample_rate = 11025;
146  s->bit_rate = 8 * (DSS_FRAME_SIZE - 1) * st->codecpar->sample_rate
147  * 512 / (506 * 264);
148  } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
150  st->codecpar->sample_rate = 8000;
151  } else {
152  avpriv_request_sample(s, "Support for codec %x in DSS",
153  ctx->audio_codec);
154  return AVERROR_PATCHWELCOME;
155  }
156 
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 
183 static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *data)
184 {
185  int i;
186 
187  if (ctx->swap) {
188  for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
189  data[i] = data[i + 4];
190 
191  /* Zero the padding. */
192  data[DSS_FRAME_SIZE] = 0;
193  data[1] = ctx->dss_sp_swap_byte;
194  } else {
195  ctx->dss_sp_swap_byte = data[DSS_FRAME_SIZE - 2];
196  }
197 
198  /* make sure byte 40 is always 0 */
199  data[DSS_FRAME_SIZE - 2] = 0;
200  ctx->swap ^= 1;
201 }
202 
204 {
205  DSSDemuxContext *ctx = s->priv_data;
206  int read_size, ret, offset = 0, buff_offset = 0;
207  int64_t pos = avio_tell(s->pb);
208 
209  if (ctx->counter == 0)
211 
212  if (ctx->swap) {
213  read_size = DSS_FRAME_SIZE - 2;
214  buff_offset = 3;
215  } else
216  read_size = DSS_FRAME_SIZE;
217 
219  if (ret < 0)
220  return ret;
221 
222  pkt->duration = 264;
223  pkt->pos = pos;
224  pkt->stream_index = 0;
225 
226  if (ctx->counter < read_size) {
227  ret = avio_read(s->pb, pkt->data + buff_offset,
228  ctx->counter);
229  if (ret < ctx->counter)
230  goto error_eof;
231 
232  offset = ctx->counter;
234  }
235  ctx->counter -= read_size;
236 
237  /* This will write one byte into pkt's padding if buff_offset == 3 */
238  ret = avio_read(s->pb, pkt->data + offset + buff_offset,
239  read_size - offset);
240  if (ret < read_size - offset)
241  goto error_eof;
242 
244 
245  if (ctx->dss_sp_swap_byte < 0) {
246  return AVERROR(EAGAIN);
247  }
248 
249  return 0;
250 
251 error_eof:
252  return ret < 0 ? ret : AVERROR_EOF;
253 }
254 
256 {
257  DSSDemuxContext *ctx = s->priv_data;
258  AVStream *st = s->streams[0];
259  int size, byte, ret, offset;
260  int64_t pos = avio_tell(s->pb);
261 
262  if (ctx->counter == 0)
264 
265  /* We make one byte-step here. Don't forget to add offset. */
266  byte = avio_r8(s->pb);
267  if (byte == 0xff)
268  return AVERROR_INVALIDDATA;
269 
270  size = frame_size[byte & 3];
271 
272  ctx->packet_size = size;
273  ctx->counter--;
274 
276  if (ret < 0)
277  return ret;
278  pkt->pos = pos;
279 
280  pkt->data[0] = byte;
281  offset = 1;
282  pkt->duration = 240;
283  s->bit_rate = 8LL * size-- * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
284 
285  pkt->stream_index = 0;
286 
287  if (ctx->counter < size) {
288  ret = avio_read(s->pb, pkt->data + offset,
289  ctx->counter);
290  if (ret < ctx->counter)
291  return ret < 0 ? ret : AVERROR_EOF;
292 
293  offset += ctx->counter;
294  size -= ctx->counter;
295  ctx->counter = 0;
297  }
298  ctx->counter -= size;
299 
300  ret = avio_read(s->pb, pkt->data + offset, size);
301  if (ret < size)
302  return ret < 0 ? ret : AVERROR_EOF;
303 
304  return 0;
305 }
306 
308 {
309  DSSDemuxContext *ctx = s->priv_data;
310 
312  return dss_sp_read_packet(s, pkt);
313  else
314  return dss_723_1_read_packet(s, pkt);
315 }
316 
317 static int dss_read_seek(AVFormatContext *s, int stream_index,
318  int64_t timestamp, int flags)
319 {
320  DSSDemuxContext *ctx = s->priv_data;
321  int64_t ret, seekto;
323  int offset;
324 
326  seekto = timestamp / 264 * 41 / 506 * 512;
327  else
328  seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
329 
330  if (seekto < 0)
331  seekto = 0;
332 
333  seekto += ctx->dss_header_size;
334 
335  ret = avio_seek(s->pb, seekto, SEEK_SET);
336  if (ret < 0)
337  return ret;
338 
340  ctx->swap = !!(header[0] & 0x80);
341  offset = 2*header[1] + 2*ctx->swap;
343  return AVERROR_INVALIDDATA;
345  ctx->counter = 0;
347  } else {
348  ctx->counter = DSS_BLOCK_SIZE - offset;
350  }
351  ctx->dss_sp_swap_byte = -1;
352  return 0;
353 }
354 
355 
357  .name = "dss",
358  .long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
359  .priv_data_size = sizeof(DSSDemuxContext),
364  .extensions = "dss"
365 };
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: options.c:237
AVCodecParameters::codec_type
enum AVMediaType codec_type
General type of the encoded data.
Definition: codec_par.h:57
DSS_HEAD_OFFSET_COMMENT
#define DSS_HEAD_OFFSET_COMMENT
Definition: dss.c:39
AVERROR_EOF
#define AVERROR_EOF
End of file.
Definition: error.h:57
AVPacket::data
uint8_t * data
Definition: packet.h:374
data
const char data[16]
Definition: mxf.c:146
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:356
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:392
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:255
DSS_HEAD_OFFSET_ACODEC
#define DSS_HEAD_OFFSET_ACODEC
Definition: dss.c:35
dss_sp_byte_swap
static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *data)
Definition: dss.c:183
AVPROBE_SCORE_MAX
#define AVPROBE_SCORE_MAX
maximum score
Definition: avformat.h:465
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:763
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:505
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:72
dss_read_seek
static int dss_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
Definition: dss.c:317
pkt
AVPacket * pkt
Definition: movenc.c:59
AVInputFormat
Definition: avformat.h:656
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:256
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:97
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:661
AVProbeData::buf
unsigned char * buf
Buffer must have AVPROBE_PADDING_SIZE of extra allocated bytes filled with zero.
Definition: avformat.h:455
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:67
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:174
dss_sp_read_packet
static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:203
AVFormatContext
Format I/O context.
Definition: avformat.h:1216
internal.h
AVStream::codecpar
AVCodecParameters * codecpar
Codec parameters associated with this stream.
Definition: avformat.h:1108
read_header
static int read_header(FFV1Context *f)
Definition: ffv1dec.c:530
NULL
#define NULL
Definition: coverity.c:32
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
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:485
AVProbeData
This structure contains the data a format has to probe a file.
Definition: avformat.h:453
AVFormatContext::audio_codec
const AVCodec * audio_codec
Forced audio codec.
Definition: avformat.h:1693
AVCodecParameters::ch_layout
AVChannelLayout ch_layout
Audio only.
Definition: codec_par.h:212
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:177
DSS_ACODEC_G723_1
#define DSS_ACODEC_G723_1
Definition: dss.c:37
AVIOContext
Bytestream IO Context.
Definition: avio.h:162
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:115
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:293
DSSDemuxContext::packet_size
int packet_size
Definition: dss.c:54
size
int size
Definition: twinvq_data.h:10344
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:632
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:313
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:90
ff_dss_demuxer
const AVInputFormat ff_dss_demuxer
Definition: dss.c:356
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:499
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:264
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:948
avio_seek
int64_t avio_seek(AVIOContext *s, int64_t offset, int whence)
fseek() equivalent for AVIOContext.
Definition: aviobuf.c:260
dss_read_packet
static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
Definition: dss.c:307
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:92
channel_layout.h
avio_read
int avio_read(AVIOContext *s, unsigned char *buf, int size)
Read size bytes from AVIOContext into buf.
Definition: aviobuf.c:641
AVPacket::stream_index
int stream_index
Definition: packet.h:376
avio_skip
int64_t avio_skip(AVIOContext *s, int64_t offset)
Skip given number of bytes forward.
Definition: aviobuf.c:347
AVFormatContext::packet_size
unsigned int packet_size
Definition: avformat.h:1327
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
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:61
AVPacket
This structure stores compressed data.
Definition: packet.h:351
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:71
AVPacket::pos
int64_t pos
byte position in stream, -1 if unknown
Definition: packet.h:394
dss_read_header
static int dss_read_header(AVFormatContext *s)
Definition: dss.c:112
d
d
Definition: ffmpeg_filter.c:156
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:561
DSSDemuxContext::swap
int swap
Definition: dss.c:51
dss_probe
static int dss_probe(const AVProbeData *p)
Definition: dss.c:58
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:988
DSSDemuxContext::dss_header_size
int dss_header_size
Definition: dss.c:55
snprintf
#define snprintf
Definition: snprintf.h:34