1 /*
2 * DHAV demuxer
3 *
4 * Copyright (c) 2018 Paul B Mahol
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include "libavutil/parseutils.h"
24 #include "avio_internal.h"
25 #include "avformat.h"
26 #include "internal.h"
27
28 typedef struct DHAVContext {
29 unsigned type;
30 unsigned subtype;
31 unsigned channel;
32 unsigned frame_subnumber;
33 unsigned frame_number;
34 unsigned date;
35 unsigned timestamp;
36 int width, height;
37 int video_codec;
38 int frame_rate;
39 int audio_channels;
40 int audio_codec;
41 int sample_rate;
42 int64_t last_good_pos;
43 int64_t duration;
44
45 int video_stream_index;
46 int audio_stream_index;
47 } DHAVContext;
48
49 typedef struct DHAVStream {
50 int64_t last_timestamp;
51 int64_t last_time;
52 int64_t pts;
53 } DHAVStream;
54
dhav_probe(const AVProbeData * p)55 static int dhav_probe(const AVProbeData *p)
56 {
57 if (!memcmp(p->buf, "DAHUA", 5))
58 return AVPROBE_SCORE_MAX;
59
60 if (memcmp(p->buf, "DHAV", 4))
61 return 0;
62
63 if (p->buf[4] == 0xf0 ||
64 p->buf[4] == 0xf1 ||
65 p->buf[4] == 0xfc ||
66 p->buf[4] == 0xfd)
67 return AVPROBE_SCORE_MAX;
68 return 0;
69 }
70
71 static const uint32_t sample_rates[] = {
72 8000, 4000, 8000, 11025, 16000,
73 20000, 22050, 32000, 44100, 48000,
74 96000, 192000, 64000,
75 };
76
parse_ext(AVFormatContext * s,int length)77 static int parse_ext(AVFormatContext *s, int length)
78 {
79 DHAVContext *dhav = s->priv_data;
80 int index, ret = 0;
81
82 while (length > 0) {
83 int type = avio_r8(s->pb);
84
85 switch (type) {
86 case 0x80:
87 ret = avio_skip(s->pb, 1);
88 dhav->width = 8 * avio_r8(s->pb);
89 dhav->height = 8 * avio_r8(s->pb);
90 length -= 4;
91 break;
92 case 0x81:
93 ret = avio_skip(s->pb, 1);
94 dhav->video_codec = avio_r8(s->pb);
95 dhav->frame_rate = avio_r8(s->pb);
96 length -= 4;
97 break;
98 case 0x82:
99 ret = avio_skip(s->pb, 3);
100 dhav->width = avio_rl16(s->pb);
101 dhav->height = avio_rl16(s->pb);
102 length -= 8;
103 break;
104 case 0x83:
105 dhav->audio_channels = avio_r8(s->pb);
106 dhav->audio_codec = avio_r8(s->pb);
107 index = avio_r8(s->pb);
108 if (index < FF_ARRAY_ELEMS(sample_rates)) {
109 dhav->sample_rate = sample_rates[index];
110 } else {
111 dhav->sample_rate = 8000;
112 }
113 length -= 4;
114 break;
115 case 0x88:
116 ret = avio_skip(s->pb, 7);
117 length -= 8;
118 break;
119 case 0x8c:
120 ret = avio_skip(s->pb, 1);
121 dhav->audio_channels = avio_r8(s->pb);
122 dhav->audio_codec = avio_r8(s->pb);
123 index = avio_r8(s->pb);
124 if (index < FF_ARRAY_ELEMS(sample_rates)) {
125 dhav->sample_rate = sample_rates[index];
126 } else {
127 dhav->sample_rate = 8000;
128 }
129 ret = avio_skip(s->pb, 3);
130 length -= 8;
131 break;
132 case 0x91:
133 case 0x92:
134 case 0x93:
135 case 0x95:
136 case 0x9a:
137 case 0x9b: // sample aspect ratio
138 case 0xb3:
139 ret = avio_skip(s->pb, 7);
140 length -= 8;
141 break;
142 case 0x84:
143 case 0x85:
144 case 0x8b:
145 case 0x94:
146 case 0x96:
147 case 0xa0:
148 case 0xb2:
149 case 0xb4:
150 ret = avio_skip(s->pb, 3);
151 length -= 4;
152 break;
153 default:
154 av_log(s, AV_LOG_INFO, "Unknown type: %X, skipping rest of header.\n", type);
155 ret = avio_skip(s->pb, length - 1);
156 length = 0;
157 }
158
159 if (ret < 0)
160 return ret;
161 }
162
163 return 0;
164 }
165
read_chunk(AVFormatContext * s)166 static int read_chunk(AVFormatContext *s)
167 {
168 DHAVContext *dhav = s->priv_data;
169 int frame_length, ext_length;
170 int64_t start, end;
171 int ret;
172
173 if (avio_feof(s->pb))
174 return AVERROR_EOF;
175
176 while (avio_r8(s->pb) != 'D' || avio_r8(s->pb) != 'H' || avio_r8(s->pb) != 'A' || avio_r8(s->pb) != 'V') {
177 if (avio_feof(s->pb))
178 return AVERROR_EOF;
179 }
180
181 start = avio_tell(s->pb) - 4;
182 dhav->last_good_pos = start;
183 dhav->type = avio_r8(s->pb);
184 dhav->subtype = avio_r8(s->pb);
185 dhav->channel = avio_r8(s->pb);
186 dhav->frame_subnumber = avio_r8(s->pb);
187 dhav->frame_number = avio_rl32(s->pb);
188 frame_length = avio_rl32(s->pb);
189 dhav->date = avio_rl32(s->pb);
190
191 if (frame_length < 24)
192 return AVERROR_INVALIDDATA;
193 if (dhav->type == 0xf1) {
194 ret = avio_skip(s->pb, frame_length - 20);
195 return ret < 0 ? ret : 0;
196 }
197
198 dhav->timestamp = avio_rl16(s->pb);
199 ext_length = avio_r8(s->pb);
200 avio_skip(s->pb, 1); // checksum
201
202 ret = parse_ext(s, ext_length);
203 if (ret < 0)
204 return ret;
205
206 end = avio_tell(s->pb);
207
208 return frame_length - 8 - (end - start);
209 }
210
get_timeinfo(unsigned date,struct tm * timeinfo)211 static void get_timeinfo(unsigned date, struct tm *timeinfo)
212 {
213 int year, month, day, hour, min, sec;
214
215 sec = date & 0x3F;
216 min = (date >> 6) & 0x3F;
217 hour = (date >> 12) & 0x1F;
218 day = (date >> 17) & 0x1F;
219 month = (date >> 22) & 0x0F;
220 year = ((date >> 26) & 0x3F) + 2000;
221
222 timeinfo->tm_year = year - 1900;
223 timeinfo->tm_mon = month - 1;
224 timeinfo->tm_mday = day;
225 timeinfo->tm_hour = hour;
226 timeinfo->tm_min = min;
227 timeinfo->tm_sec = sec;
228 }
229
get_duration(AVFormatContext * s)230 static int64_t get_duration(AVFormatContext *s)
231 {
232 DHAVContext *dhav = s->priv_data;
233 int64_t start_pos = avio_tell(s->pb);
234 int64_t start = 0, end = 0;
235 struct tm timeinfo;
236
237 if (!s->pb->seekable)
238 return 0;
239
240 avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
241 if (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
242 int seek_back = avio_rl32(s->pb);
243
244 avio_seek(s->pb, -seek_back, SEEK_CUR);
245 read_chunk(s);
246 get_timeinfo(dhav->date, &timeinfo);
247 end = av_timegm(&timeinfo) * 1000LL;
248 } else {
249 avio_seek(s->pb, start_pos, SEEK_SET);
250 return 0;
251 }
252
253 avio_seek(s->pb, start_pos, SEEK_SET);
254
255 read_chunk(s);
256 get_timeinfo(dhav->date, &timeinfo);
257 start = av_timegm(&timeinfo) * 1000LL;
258
259 avio_seek(s->pb, start_pos, SEEK_SET);
260
261 return end - start;
262 }
263
dhav_read_header(AVFormatContext * s)264 static int dhav_read_header(AVFormatContext *s)
265 {
266 DHAVContext *dhav = s->priv_data;
267 uint8_t signature[5];
268
269 ffio_ensure_seekback(s->pb, 5);
270 avio_read(s->pb, signature, sizeof(signature));
271 if (!memcmp(signature, "DAHUA", 5)) {
272 avio_skip(s->pb, 0x400 - 5);
273 dhav->last_good_pos = avio_tell(s->pb);
274 } else {
275 if (!memcmp(signature, "DHAV", 4)) {
276 avio_seek(s->pb, -5, SEEK_CUR);
277 dhav->last_good_pos = avio_tell(s->pb);
278 } else if (s->pb->seekable) {
279 avio_seek(s->pb, avio_size(s->pb) - 8, SEEK_SET);
280 while (avio_rl32(s->pb) == MKTAG('d','h','a','v')) {
281 int seek_back;
282
283 seek_back = avio_rl32(s->pb) + 8;
284 if (seek_back < 9)
285 break;
286 dhav->last_good_pos = avio_tell(s->pb);
287 avio_seek(s->pb, -seek_back, SEEK_CUR);
288 }
289 avio_seek(s->pb, dhav->last_good_pos, SEEK_SET);
290 }
291 }
292
293 dhav->duration = get_duration(s);
294 dhav->last_good_pos = avio_tell(s->pb);
295 s->ctx_flags |= AVFMTCTX_NOHEADER;
296 dhav->video_stream_index = -1;
297 dhav->audio_stream_index = -1;
298
299 return 0;
300 }
301
get_pts(AVFormatContext * s,int stream_index)302 static int64_t get_pts(AVFormatContext *s, int stream_index)
303 {
304 DHAVStream *dst = s->streams[stream_index]->priv_data;
305 DHAVContext *dhav = s->priv_data;
306 struct tm timeinfo;
307 time_t t;
308
309 get_timeinfo(dhav->date, &timeinfo);
310
311 t = av_timegm(&timeinfo);
312 if (dst->last_time == t) {
313 int64_t diff = dhav->timestamp - dst->last_timestamp;
314
315 if (diff < 0)
316 diff += 65535;
317 dst->pts += diff;
318 } else {
319 dst->pts = t * 1000LL;
320 }
321
322 dst->last_time = t;
323 dst->last_timestamp = dhav->timestamp;
324
325 return dst->pts;
326 }
327
dhav_read_packet(AVFormatContext * s,AVPacket * pkt)328 static int dhav_read_packet(AVFormatContext *s, AVPacket *pkt)
329 {
330 DHAVContext *dhav = s->priv_data;
331 int size, ret, stream_index;
332
333 retry:
334 while ((ret = read_chunk(s)) == 0)
335 ;
336
337 if (ret < 0)
338 return ret;
339
340 if (dhav->type == 0xfd && dhav->video_stream_index == -1) {
341 AVStream *st = avformat_new_stream(s, NULL);
342 DHAVStream *dst;
343
344 if (!st)
345 return AVERROR(ENOMEM);
346
347 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
348 switch (dhav->video_codec) {
349 case 0x1: st->codecpar->codec_id = AV_CODEC_ID_MPEG4; break;
350 case 0x3: st->codecpar->codec_id = AV_CODEC_ID_MJPEG; break;
351 case 0x2:
352 case 0x4:
353 case 0x8: st->codecpar->codec_id = AV_CODEC_ID_H264; break;
354 case 0xc: st->codecpar->codec_id = AV_CODEC_ID_HEVC; break;
355 default: avpriv_request_sample(s, "Unknown video codec %X", dhav->video_codec);
356 }
357 st->duration = dhav->duration;
358 st->codecpar->width = dhav->width;
359 st->codecpar->height = dhav->height;
360 st->avg_frame_rate.num = dhav->frame_rate;
361 st->avg_frame_rate.den = 1;
362 st->priv_data = dst = av_mallocz(sizeof(DHAVStream));
363 if (!st->priv_data)
364 return AVERROR(ENOMEM);
365 dst->last_time = AV_NOPTS_VALUE;
366 dhav->video_stream_index = st->index;
367
368 avpriv_set_pts_info(st, 64, 1, 1000);
369 } else if (dhav->type == 0xf0 && dhav->audio_stream_index == -1) {
370 AVStream *st = avformat_new_stream(s, NULL);
371 DHAVStream *dst;
372
373 if (!st)
374 return AVERROR(ENOMEM);
375
376 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
377 switch (dhav->audio_codec) {
378 case 0x07: st->codecpar->codec_id = AV_CODEC_ID_PCM_S8; break;
379 case 0x0c: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE; break;
380 case 0x10: st->codecpar->codec_id = AV_CODEC_ID_PCM_S16LE; break;
381 case 0x0a: st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW; break;
382 case 0x16: st->codecpar->codec_id = AV_CODEC_ID_PCM_MULAW; break;
383 case 0x0e: st->codecpar->codec_id = AV_CODEC_ID_PCM_ALAW; break;
384 case 0x1a: st->codecpar->codec_id = AV_CODEC_ID_AAC; break;
385 case 0x1f: st->codecpar->codec_id = AV_CODEC_ID_MP2; break;
386 case 0x21: st->codecpar->codec_id = AV_CODEC_ID_MP3; break;
387 case 0x0d: st->codecpar->codec_id = AV_CODEC_ID_ADPCM_MS; break;
388 default: avpriv_request_sample(s, "Unknown audio codec %X", dhav->audio_codec);
389 }
390 st->duration = dhav->duration;
391 st->codecpar->channels = dhav->audio_channels;
392 st->codecpar->sample_rate = dhav->sample_rate;
393 st->priv_data = dst = av_mallocz(sizeof(DHAVStream));
394 if (!st->priv_data)
395 return AVERROR(ENOMEM);
396 dst->last_time = AV_NOPTS_VALUE;
397 dhav->audio_stream_index = st->index;
398
399 avpriv_set_pts_info(st, 64, 1, 1000);
400 }
401
402 stream_index = dhav->type == 0xf0 ? dhav->audio_stream_index : dhav->video_stream_index;
403 if (stream_index < 0) {
404 avio_skip(s->pb, ret);
405 if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
406 avio_skip(s->pb, 4);
407 goto retry;
408 }
409
410 size = ret;
411 ret = av_get_packet(s->pb, pkt, size);
412 if (ret < 0)
413 return ret;
414 pkt->stream_index = stream_index;
415 if (dhav->type != 0xfc)
416 pkt->flags |= AV_PKT_FLAG_KEY;
417 pkt->duration = 1;
418 if (pkt->stream_index >= 0)
419 pkt->pts = get_pts(s, pkt->stream_index);
420 pkt->pos = dhav->last_good_pos;
421 if (avio_rl32(s->pb) == MKTAG('d','h','a','v'))
422 avio_skip(s->pb, 4);
423
424 return ret;
425 }
426
dhav_read_seek(AVFormatContext * s,int stream_index,int64_t timestamp,int flags)427 static int dhav_read_seek(AVFormatContext *s, int stream_index,
428 int64_t timestamp, int flags)
429 {
430 DHAVContext *dhav = s->priv_data;
431 AVStream *st = s->streams[stream_index];
432 int index = av_index_search_timestamp(st, timestamp, flags);
433 int64_t pts;
434
435 if (index < 0)
436 return -1;
437 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)
438 return -1;
439
440 pts = st->index_entries[index].timestamp;
441
442 for (int n = 0; n < s->nb_streams; n++) {
443 AVStream *st = s->streams[n];
444 DHAVStream *dst = st->priv_data;
445
446 dst->pts = pts;
447 dst->last_time = AV_NOPTS_VALUE;
448 }
449 dhav->last_good_pos = avio_tell(s->pb);
450
451 return 0;
452 }
453
454 AVInputFormat ff_dhav_demuxer = {
455 .name = "dhav",
456 .long_name = NULL_IF_CONFIG_SMALL("Video DAV"),
457 .priv_data_size = sizeof(DHAVContext),
458 .read_probe = dhav_probe,
459 .read_header = dhav_read_header,
460 .read_packet = dhav_read_packet,
461 .read_seek = dhav_read_seek,
462 .extensions = "dav",
463 .flags = AVFMT_GENERIC_INDEX | AVFMT_NO_BYTE_SEEK | AVFMT_TS_DISCONT | AVFMT_TS_NONSTRICT,
464 };
465