FFmpeg coverage

Directory: ../../../ffmpeg/
File: src/libavformat/dss.c
Date: 2025-11-04 10:33:36
Exec Total Coverage
Lines: 130 175 74.3%
Functions: 9 10 90.0%
Branches: 39 78 50.0%
Line Branch Exec Source
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/channel_layout.h"
23 #include "libavutil/intreadwrite.h"
24 #include "libavutil/mem.h"
25
26 #include "avformat.h"
27 #include "demux.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;
54 int dss_sp_swap_byte;
55
56 int packet_size;
57 int dss_header_size;
58 } DSSDemuxContext;
59
60 7282 static int dss_probe(const AVProbeData *p)
61 {
62
2/2
✓ Branch 0 taken 7280 times.
✓ Branch 1 taken 2 times.
 7282 if ( AV_RL32(p->buf) != MKTAG(0x2, 'd', 's', 's')
63
1/2
✓ Branch 0 taken 7280 times.
✗ Branch 1 not taken.
 7280 && AV_RL32(p->buf) != MKTAG(0x3, 'd', 's', 's'))
64 7280 return 0;
65
66 2 return AVPROBE_SCORE_MAX;
67 }
68
69 2 static int dss_read_metadata_date(AVFormatContext *s, unsigned int offset,
70 const char *key)
71 {
72 2 AVIOContext *pb = s->pb;
73 2 char datetime[64], string[DSS_TIME_SIZE + 1] = { 0 };
74 int y, month, d, h, minute, sec;
75 int ret;
76
77 2 avio_seek(pb, offset, SEEK_SET);
78
79 2 ret = avio_read(s->pb, string, DSS_TIME_SIZE);
80
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (ret < DSS_TIME_SIZE)
81 ✗ return ret < 0 ? ret : AVERROR_EOF;
82
83
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (sscanf(string, "%2d%2d%2d%2d%2d%2d", &y, &month, &d, &h, &minute, &sec) != 6)
84 ✗ return AVERROR_INVALIDDATA;
85 /* We deal with a two-digit year here, so set the default date to 2000
86 * and hope it will never be used in the next century. */
87 2 snprintf(datetime, sizeof(datetime), "%.4d-%.2d-%.2dT%.2d:%.2d:%.2d",
88 y + 2000, month, d, h, minute, sec);
89 2 return av_dict_set(&s->metadata, key, datetime, 0);
90 }
91
92 4 static int dss_read_metadata_string(AVFormatContext *s, unsigned int offset,
93 unsigned int size, const char *key)
94 {
95 4 AVIOContext *pb = s->pb;
96 char *value;
97 int ret;
98
99 4 avio_seek(pb, offset, SEEK_SET);
100
101 4 value = av_mallocz(size + 1);
102
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (!value)
103 ✗ return AVERROR(ENOMEM);
104
105 4 ret = avio_read(s->pb, value, size);
106
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 4 times.
 4 if (ret < size) {
107 ✗ av_free(value);
108 ✗ return ret < 0 ? ret : AVERROR_EOF;
109 }
110
111 4 return av_dict_set(&s->metadata, key, value, AV_DICT_DONT_STRDUP_VAL);
112 }
113
114 2 static int dss_read_header(AVFormatContext *s)
115 {
116 2 DSSDemuxContext *ctx = s->priv_data;
117 2 AVIOContext *pb = s->pb;
118 AVStream *st;
119 int ret, version;
120
121 2 st = avformat_new_stream(s, NULL);
122
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (!st)
123 ✗ return AVERROR(ENOMEM);
124
125 2 version = avio_r8(pb);
126 2 ctx->dss_header_size = version * DSS_BLOCK_SIZE;
127
128 2 ret = dss_read_metadata_string(s, DSS_HEAD_OFFSET_AUTHOR,
129 DSS_AUTHOR_SIZE, "author");
130
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (ret)
131 ✗ return ret;
132
133 2 ret = dss_read_metadata_date(s, DSS_HEAD_OFFSET_END_TIME, "date");
134
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (ret)
135 ✗ return ret;
136
137 2 ret = dss_read_metadata_string(s, DSS_HEAD_OFFSET_COMMENT,
138 DSS_COMMENT_SIZE, "comment");
139
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (ret)
140 ✗ return ret;
141
142 2 avio_seek(pb, DSS_HEAD_OFFSET_ACODEC, SEEK_SET);
143 2 ctx->audio_codec = avio_r8(pb);
144
145
2/2
✓ Branch 0 taken 1 times.
✓ Branch 1 taken 1 times.
 2 if (ctx->audio_codec == DSS_ACODEC_DSS_SP) {
146 1 st->codecpar->codec_id = AV_CODEC_ID_DSS_SP;
147 1 st->codecpar->sample_rate = 11025;
148 1 s->bit_rate = 8 * (DSS_FRAME_SIZE - 1) * st->codecpar->sample_rate
149 1 * 512 / (506 * 264);
150
1/2
✓ Branch 0 taken 1 times.
✗ Branch 1 not taken.
 1 } else if (ctx->audio_codec == DSS_ACODEC_G723_1) {
151 1 st->codecpar->codec_id = AV_CODEC_ID_G723_1;
152 1 st->codecpar->sample_rate = 8000;
153 } else {
154 ✗ avpriv_request_sample(s, "Support for codec %x in DSS",
155 ctx->audio_codec);
156 ✗ return AVERROR_PATCHWELCOME;
157 }
158
159 2 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
160 2 st->codecpar->ch_layout = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
161
162 2 avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
163 2 st->start_time = 0;
164
165 /* Jump over header */
166
167
1/2
✗ Branch 1 not taken.
✓ Branch 2 taken 2 times.
 2 if (avio_seek(pb, ctx->dss_header_size, SEEK_SET) != ctx->dss_header_size)
168 ✗ return AVERROR(EIO);
169
170 2 ctx->counter = 0;
171 2 ctx->swap = 0;
172
173 2 return 0;
174 }
175
176 8 static void dss_skip_audio_header(AVFormatContext *s, AVPacket *pkt)
177 {
178 8 DSSDemuxContext *ctx = s->priv_data;
179 8 AVIOContext *pb = s->pb;
180
181 8 avio_skip(pb, DSS_AUDIO_BLOCK_HEADER_SIZE);
182 8 ctx->counter += DSS_BLOCK_SIZE - DSS_AUDIO_BLOCK_HEADER_SIZE;
183 8 }
184
185 50 static void dss_sp_byte_swap(DSSDemuxContext *ctx, uint8_t *data)
186 {
187 int i;
188
189
2/2
✓ Branch 0 taken 25 times.
✓ Branch 1 taken 25 times.
 50 if (ctx->swap) {
190
2/2
✓ Branch 0 taken 500 times.
✓ Branch 1 taken 25 times.
 525 for (i = 0; i < DSS_FRAME_SIZE - 2; i += 2)
191 500 data[i] = data[i + 4];
192
193 /* Zero the padding. */
194 25 data[DSS_FRAME_SIZE] = 0;
195 25 data[1] = ctx->dss_sp_swap_byte;
196 } else {
197 25 ctx->dss_sp_swap_byte = data[DSS_FRAME_SIZE - 2];
198 }
199
200 /* make sure byte 40 is always 0 */
201 50 data[DSS_FRAME_SIZE - 2] = 0;
202 50 ctx->swap ^= 1;
203 50 }
204
205 50 static int dss_sp_read_packet(AVFormatContext *s, AVPacket *pkt)
206 {
207 50 DSSDemuxContext *ctx = s->priv_data;
208 50 int read_size, ret, offset = 0, buff_offset = 0;
209 50 int64_t pos = avio_tell(s->pb);
210
211
2/2
✓ Branch 0 taken 2 times.
✓ Branch 1 taken 48 times.
 50 if (ctx->counter == 0)
212 2 dss_skip_audio_header(s, pkt);
213
214
2/2
✓ Branch 0 taken 25 times.
✓ Branch 1 taken 25 times.
 50 if (ctx->swap) {
215 25 read_size = DSS_FRAME_SIZE - 2;
216 25 buff_offset = 3;
217 } else
218 25 read_size = DSS_FRAME_SIZE;
219
220 50 ret = av_new_packet(pkt, DSS_FRAME_SIZE);
221
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (ret < 0)
222 ✗ return ret;
223
224 50 pkt->duration = 264;
225 50 pkt->pos = pos;
226 50 pkt->stream_index = 0;
227
228
2/2
✓ Branch 0 taken 3 times.
✓ Branch 1 taken 47 times.
 50 if (ctx->counter < read_size) {
229 3 ret = avio_read(s->pb, pkt->data + buff_offset,
230 ctx->counter);
231
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 3 times.
 3 if (ret < ctx->counter)
232 ✗ goto error_eof;
233
234 3 offset = ctx->counter;
235 3 dss_skip_audio_header(s, pkt);
236 }
237 50 ctx->counter -= read_size;
238
239 /* This will write one byte into pkt's padding if buff_offset == 3 */
240 50 ret = avio_read(s->pb, pkt->data + offset + buff_offset,
241 read_size - offset);
242
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (ret < read_size - offset)
243 ✗ goto error_eof;
244
245 50 dss_sp_byte_swap(ctx, pkt->data);
246
247
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (ctx->dss_sp_swap_byte < 0) {
248 ✗ return AVERROR(EAGAIN);
249 }
250
251 50 return 0;
252
253 ✗ error_eof:
254 ✗ return ret < 0 ? ret : AVERROR_EOF;
255 }
256
257 50 static int dss_723_1_read_packet(AVFormatContext *s, AVPacket *pkt)
258 {
259 50 DSSDemuxContext *ctx = s->priv_data;
260 50 AVStream *st = s->streams[0];
261 int size, byte, ret, offset;
262 50 int64_t pos = avio_tell(s->pb);
263
264
2/2
✓ Branch 0 taken 1 times.
✓ Branch 1 taken 49 times.
 50 if (ctx->counter == 0)
265 1 dss_skip_audio_header(s, pkt);
266
267 /* We make one byte-step here. Don't forget to add offset. */
268 50 byte = avio_r8(s->pb);
269
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (byte == 0xff)
270 ✗ return AVERROR_INVALIDDATA;
271
272 50 size = frame_size[byte & 3];
273
274 50 ctx->packet_size = size;
275 50 ctx->counter--;
276
277 50 ret = av_new_packet(pkt, size);
278
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (ret < 0)
279 ✗ return ret;
280 50 pkt->pos = pos;
281
282 50 pkt->data[0] = byte;
283 50 offset = 1;
284 50 pkt->duration = 240;
285 50 s->bit_rate = 8LL * size-- * st->codecpar->sample_rate * 512 / (506 * pkt->duration);
286
287 50 pkt->stream_index = 0;
288
289
2/2
✓ Branch 0 taken 2 times.
✓ Branch 1 taken 48 times.
 50 if (ctx->counter < size) {
290 2 ret = avio_read(s->pb, pkt->data + offset,
291 ctx->counter);
292
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 2 times.
 2 if (ret < ctx->counter)
293 ✗ return ret < 0 ? ret : AVERROR_EOF;
294
295 2 offset += ctx->counter;
296 2 size -= ctx->counter;
297 2 ctx->counter = 0;
298 2 dss_skip_audio_header(s, pkt);
299 }
300 50 ctx->counter -= size;
301
302 50 ret = avio_read(s->pb, pkt->data + offset, size);
303
1/2
✗ Branch 0 not taken.
✓ Branch 1 taken 50 times.
 50 if (ret < size)
304 ✗ return ret < 0 ? ret : AVERROR_EOF;
305
306 50 return 0;
307 }
308
309 100 static int dss_read_packet(AVFormatContext *s, AVPacket *pkt)
310 {
311 100 DSSDemuxContext *ctx = s->priv_data;
312
313
2/2
✓ Branch 0 taken 50 times.
✓ Branch 1 taken 50 times.
 100 if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
314 50 return dss_sp_read_packet(s, pkt);
315 else
316 50 return dss_723_1_read_packet(s, pkt);
317 }
318
319 ✗ static int dss_read_seek(AVFormatContext *s, int stream_index,
320 int64_t timestamp, int flags)
321 {
322 ✗ DSSDemuxContext *ctx = s->priv_data;
323 int64_t ret, seekto;
324 uint8_t header[DSS_AUDIO_BLOCK_HEADER_SIZE];
325 int offset;
326
327 ✗ if (ctx->audio_codec == DSS_ACODEC_DSS_SP)
328 ✗ seekto = timestamp / 264 * 41 / 506 * 512;
329 else
330 ✗ seekto = timestamp / 240 * ctx->packet_size / 506 * 512;
331
332 ✗ if (seekto < 0)
333 ✗ seekto = 0;
334
335 ✗ seekto += ctx->dss_header_size;
336
337 ✗ ret = avio_seek(s->pb, seekto, SEEK_SET);
338 ✗ if (ret < 0)
339 ✗ return ret;
340
341 ✗ avio_read(s->pb, header, DSS_AUDIO_BLOCK_HEADER_SIZE);
342 ✗ ctx->swap = !!(header[0] & 0x80);
343 ✗ offset = 2*header[1] + 2*ctx->swap;
344 ✗ if (offset < DSS_AUDIO_BLOCK_HEADER_SIZE)
345 ✗ return AVERROR_INVALIDDATA;
346 ✗ if (offset == DSS_AUDIO_BLOCK_HEADER_SIZE) {
347 ✗ ctx->counter = 0;
348 ✗ offset = avio_skip(s->pb, -DSS_AUDIO_BLOCK_HEADER_SIZE);
349 } else {
350 ✗ ctx->counter = DSS_BLOCK_SIZE - offset;
351 ✗ offset = avio_skip(s->pb, offset - DSS_AUDIO_BLOCK_HEADER_SIZE);
352 }
353 ✗ ctx->dss_sp_swap_byte = -1;
354 ✗ return 0;
355 }
356
357
358 const FFInputFormat ff_dss_demuxer = {
359 .p.name = "dss",
360 .p.long_name = NULL_IF_CONFIG_SMALL("Digital Speech Standard (DSS)"),
361 .p.extensions = "dss",
362 .priv_data_size = sizeof(DSSDemuxContext),
363 .read_probe = dss_probe,
364 .read_header = dss_read_header,
365 .read_packet = dss_read_packet,
366 .read_seek = dss_read_seek,
367 };
368