FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/vividas.c
Date: 2024-05-03 15:42:48
Exec Total Coverage
Lines: 3 444 0.7%
Functions: 1 16 6.2%
Branches: 1 210 0.5%

Line Branch Exec Source
1 /*
2 * Vividas VIV format Demuxer
3 * Copyright (c) 2012 Krzysztof Klinikowski
4 * Copyright (c) 2010 Andrzej Szombierski
5 * based on vivparse Copyright (c) 2007 Måns Rullgård
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 /**
25 * @file
26 * @brief Vividas VIV (.viv) file demuxer
27 * @author Andrzej Szombierski [qq at kuku eu org] (2010-07)
28 * @sa http://wiki.multimedia.cx/index.php?title=Vividas_VIV
29 */
30
31 #include "libavutil/avassert.h"
32 #include "libavutil/intreadwrite.h"
33 #include "libavutil/mem.h"
34 #include "avio_internal.h"
35 #include "avformat.h"
36 #include "demux.h"
37 #include "internal.h"
38
39 #define MAX_AUDIO_SUBPACKETS 100
40
41 typedef struct VIV_SB_block {
42 int size, n_packets;
43 int64_t byte_offset;
44 int64_t packet_offset;
45 } VIV_SB_block;
46
47 typedef struct VIV_SB_entry {
48 int size, flag;
49 } VIV_SB_entry;
50
51 typedef struct VIV_AudioSubpacket {
52 int start, pcm_bytes;
53 } VIV_AudioSubpacket;
54
55 typedef struct VividasDemuxContext {
56 int n_sb_blocks;
57 VIV_SB_block *sb_blocks;
58 int num_audio;
59
60 uint32_t sb_key;
61 int64_t sb_offset;
62
63 int current_sb, current_sb_entry;
64 uint8_t *sb_buf;
65 AVIOContext *sb_pb;
66 int n_sb_entries;
67 VIV_SB_entry *sb_entries;
68
69 int n_audio_subpackets;
70 int current_audio_subpacket;
71
72 int64_t audio_sample;
73
74 VIV_AudioSubpacket audio_subpackets[MAX_AUDIO_SUBPACKETS];
75 } VividasDemuxContext;
76
77 7128 static int viv_probe(const AVProbeData *p)
78 {
79
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7128 if (memcmp(p->buf, "vividas03", 9))
80 7128 return 0;
81
82 return AVPROBE_SCORE_MAX;
83 }
84
85 static const uint8_t keybits[32] = {
86 20, 52, 111, 10, 27, 71, 142, 53,
87 82, 138, 1, 78, 86, 121, 183, 85,
88 105, 152, 39, 140, 172, 11, 64, 144,
89 155, 6, 71, 163, 186, 49, 126, 43,
90 };
91
92 static uint32_t decode_key(uint8_t *buf)
93 {
94 uint32_t key = 0;
95
96 for (int i = 0; i < 32; i++) {
97 unsigned p = keybits[i];
98 key |= ((buf[p] >> ((i*5+3)&7)) & 1u) << i;
99 }
100
101 return key;
102 }
103
104 static void put_v(uint8_t *p, unsigned v)
105 {
106 if (v>>28)
107 *p++ = ((v>>28)&0x7f)|0x80;
108 if (v>>21)
109 *p++ = ((v>>21)&0x7f)|0x80;
110 if (v>>14)
111 *p++ = ((v>>14)&0x7f)|0x80;
112 if (v>>7)
113 *p++ = ((v>>7)&0x7f)|0x80;
114 }
115
116 static unsigned recover_key(unsigned char sample[4], unsigned expected_size)
117 {
118 unsigned char plaintext[8] = { 'S', 'B' };
119
120 put_v(plaintext+2, expected_size);
121
122 return AV_RL32(sample) ^ AV_RL32(plaintext);
123 }
124
125 static void xor_block(void *p1, void *p2, unsigned size, int key, unsigned *key_ptr)
126 {
127 unsigned *d1 = p1;
128 unsigned *d2 = p2;
129 unsigned k = *key_ptr;
130
131 size >>= 2;
132
133 while (size > 0) {
134 *d2 = *d1 ^ (HAVE_BIGENDIAN ? av_bswap32(k) : k);
135 k += key;
136 d1++;
137 d2++;
138 size--;
139 }
140
141 *key_ptr = k;
142 }
143
144 static void decode_block(uint8_t *src, uint8_t *dest, unsigned size,
145 uint32_t key, uint32_t *key_ptr,
146 int align)
147 {
148 unsigned s = size;
149 char tmp[4];
150 int a2;
151
152 if (!size)
153 return;
154
155 align &= 3;
156 a2 = (4 - align) & 3;
157
158 if (align) {
159 uint32_t tmpkey = *key_ptr - key;
160 if (a2 > s) {
161 a2 = s;
162 avpriv_request_sample(NULL, "tiny aligned block");
163 }
164 memcpy(tmp + align, src, a2);
165 xor_block(tmp, tmp, 4, key, &tmpkey);
166 memcpy(dest, tmp + align, a2);
167 s -= a2;
168 }
169
170 if (s >= 4) {
171 xor_block(src + a2, dest + a2, s & ~3,
172 key, key_ptr);
173 s &= 3;
174 }
175
176 if (s) {
177 size -= s;
178 memcpy(tmp, src + size, s);
179 xor_block(&tmp, &tmp, 4, key, key_ptr);
180 memcpy(dest + size, tmp, s);
181 }
182 }
183
184 static uint32_t get_v(uint8_t *p, int len)
185 {
186 uint32_t v = 0;
187 const uint8_t *end = p + len;
188
189 do {
190 if (p >= end || v >= UINT_MAX / 128 - *p)
191 return v;
192 v <<= 7;
193 v += *p & 0x7f;
194 } while (*p++ & 0x80);
195
196 return v;
197 }
198
199 static uint8_t *read_vblock(AVIOContext *src, uint32_t *size,
200 uint32_t key, uint32_t *k2, int align)
201 {
202 uint8_t tmp[4];
203 uint8_t *buf;
204 unsigned n;
205
206 if (avio_read(src, tmp, 4) != 4)
207 return NULL;
208
209 decode_block(tmp, tmp, 4, key, k2, align);
210
211 n = get_v(tmp, 4);
212 if (n < 4)
213 return NULL;
214
215 buf = av_malloc(n);
216 if (!buf)
217 return NULL;
218
219 *size = n;
220 n -= 4;
221
222 memcpy(buf, tmp, 4);
223
224 if (avio_read(src, buf + 4, n) == n) {
225 decode_block(buf + 4, buf + 4, n, key, k2, align);
226 } else {
227 av_free(buf);
228 buf = NULL;
229 }
230
231 return buf;
232 }
233
234 static uint8_t *read_sb_block(AVIOContext *src, unsigned *size,
235 uint32_t *key, unsigned expected_size)
236 {
237 uint8_t *buf;
238 uint8_t ibuf[8], sbuf[8];
239 uint32_t k2;
240 unsigned n;
241
242 if (avio_read(src, ibuf, 8) < 8)
243 return NULL;
244
245 k2 = *key;
246 decode_block(ibuf, sbuf, 8, *key, &k2, 0);
247
248 n = get_v(sbuf+2, 6);
249
250 if (sbuf[0] != 'S' || sbuf[1] != 'B' || (expected_size>0 && n != expected_size)) {
251 uint32_t tmpkey = recover_key(ibuf, expected_size);
252 k2 = tmpkey;
253 decode_block(ibuf, sbuf, 8, tmpkey, &k2, 0);
254 n = get_v(sbuf+2, 6);
255 if (sbuf[0] != 'S' || sbuf[1] != 'B' || expected_size != n)
256 return NULL;
257 *key = tmpkey;
258 }
259
260 if (n < 8)
261 return NULL;
262
263 buf = av_malloc(n);
264 if (!buf)
265 return NULL;
266
267 memcpy(buf, sbuf, 8);
268
269 *size = n;
270 n -= 8;
271
272 if (avio_read(src, buf+8, n) != n) {
273 av_free(buf);
274 return NULL;
275 }
276
277 decode_block(buf + 8, buf + 8, n, *key, &k2, 0);
278
279 return buf;
280 }
281
282 static int track_header(VividasDemuxContext *viv, AVFormatContext *s,
283 const uint8_t *buf, int size)
284 {
285 int i, j, ret;
286 int64_t off;
287 int val_1;
288 int num_video;
289 FFIOContext pb0;
290 AVIOContext *const pb = &pb0.pub;
291
292 ffio_init_read_context(&pb0, buf, size);
293
294 ffio_read_varlen(pb); // track_header_len
295 avio_r8(pb); // '1'
296
297 val_1 = ffio_read_varlen(pb);
298
299 for (i=0;i<val_1;i++) {
300 int c = avio_r8(pb);
301 if (avio_feof(pb))
302 return AVERROR_EOF;
303 for (j=0;j<c;j++) {
304 if (avio_feof(pb))
305 return AVERROR_EOF;
306 avio_r8(pb); // val_3
307 avio_r8(pb); // val_4
308 }
309 }
310
311 avio_r8(pb); // num_streams
312
313 off = avio_tell(pb);
314 off += ffio_read_varlen(pb); // val_5
315
316 avio_r8(pb); // '2'
317 num_video = avio_r8(pb);
318
319 avio_seek(pb, off, SEEK_SET);
320 if (num_video != 1) {
321 av_log(s, AV_LOG_ERROR, "number of video tracks %d is not 1\n", num_video);
322 return AVERROR_PATCHWELCOME;
323 }
324
325 for (i = 0; i < num_video; i++) {
326 AVStream *st = avformat_new_stream(s, NULL);
327 int num, den;
328
329 if (!st)
330 return AVERROR(ENOMEM);
331
332 st->id = i;
333
334 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
335 st->codecpar->codec_id = AV_CODEC_ID_VP6;
336
337 off = avio_tell(pb);
338 off += ffio_read_varlen(pb);
339 avio_r8(pb); // '3'
340 avio_r8(pb); // val_7
341 num = avio_rl32(pb); // frame_time
342 den = avio_rl32(pb); // time_base
343 avpriv_set_pts_info(st, 64, num, den);
344 st->nb_frames = avio_rl32(pb); // n frames
345 st->codecpar->width = avio_rl16(pb); // width
346 st->codecpar->height = avio_rl16(pb); // height
347 avio_r8(pb); // val_8
348 avio_rl32(pb); // val_9
349
350 avio_seek(pb, off, SEEK_SET);
351 }
352
353 off = avio_tell(pb);
354 off += ffio_read_varlen(pb); // val_10
355 avio_r8(pb); // '4'
356 viv->num_audio = avio_r8(pb);
357 avio_seek(pb, off, SEEK_SET);
358
359 if (viv->num_audio != 1)
360 av_log(s, AV_LOG_WARNING, "number of audio tracks %d is not 1\n", viv->num_audio);
361
362 for(i=0;i<viv->num_audio;i++) {
363 int q;
364 AVStream *st = avformat_new_stream(s, NULL);
365 if (!st)
366 return AVERROR(ENOMEM);
367
368 st->id = num_video + i;
369
370 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
371 st->codecpar->codec_id = AV_CODEC_ID_VORBIS;
372
373 off = avio_tell(pb);
374 off += ffio_read_varlen(pb); // length
375 avio_r8(pb); // '5'
376 avio_r8(pb); //codec_id
377 avio_rl16(pb); //codec_subid
378 st->codecpar->ch_layout.nb_channels = avio_rl16(pb); // channels
379 st->codecpar->sample_rate = avio_rl32(pb); // sample_rate
380 if (st->codecpar->sample_rate <= 0 || st->codecpar->ch_layout.nb_channels <= 0)
381 return AVERROR_INVALIDDATA;
382 avio_seek(pb, 10, SEEK_CUR); // data_1
383 q = avio_r8(pb);
384 avio_seek(pb, q, SEEK_CUR); // data_2
385 avio_r8(pb); // zeropad
386
387 if (avio_tell(pb) < off) {
388 int num_data;
389 int xd_size = 1;
390 int data_len[256];
391 int offset = 1;
392 uint8_t *p;
393 ffio_read_varlen(pb); // val_13
394 avio_r8(pb); // '19'
395 ffio_read_varlen(pb); // len_3
396 num_data = avio_r8(pb);
397 for (j = 0; j < num_data; j++) {
398 int64_t len = ffio_read_varlen(pb);
399 if (len < 0 || len > INT_MAX/2 - xd_size) {
400 return AVERROR_INVALIDDATA;
401 }
402 data_len[j] = len;
403 xd_size += len + 1 + len/255;
404 }
405
406 ret = ff_alloc_extradata(st->codecpar, xd_size);
407 if (ret < 0)
408 return ret;
409
410 p = st->codecpar->extradata;
411 p[0] = 2;
412
413 for (j = 0; j < num_data - 1; j++) {
414 unsigned delta = av_xiphlacing(&p[offset], data_len[j]);
415 av_assert0(delta <= xd_size - offset);
416 offset += delta;
417 }
418
419 for (j = 0; j < num_data; j++) {
420 int ret = avio_read(pb, &p[offset], data_len[j]);
421 if (ret < data_len[j]) {
422 st->codecpar->extradata_size = 0;
423 av_freep(&st->codecpar->extradata);
424 break;
425 }
426 av_assert0(data_len[j] <= xd_size - offset);
427 offset += data_len[j];
428 }
429
430 if (offset < st->codecpar->extradata_size)
431 st->codecpar->extradata_size = offset;
432 }
433 }
434
435 return 0;
436 }
437
438 static int track_index(VividasDemuxContext *viv, AVFormatContext *s,
439 const uint8_t *buf, unsigned size)
440 {
441 int64_t off;
442 int64_t poff;
443 int maxnp=0;
444 FFIOContext pb0;
445 AVIOContext *const pb = &pb0.pub;
446 int i;
447 int64_t filesize = avio_size(s->pb);
448 uint64_t n_sb_blocks_tmp;
449
450 ffio_init_read_context(&pb0, buf, size);
451
452 ffio_read_varlen(pb); // track_index_len
453 avio_r8(pb); // 'c'
454 n_sb_blocks_tmp = ffio_read_varlen(pb);
455 if (n_sb_blocks_tmp > size / 2)
456 return AVERROR_INVALIDDATA;
457 viv->sb_blocks = av_calloc(n_sb_blocks_tmp, sizeof(*viv->sb_blocks));
458 if (!viv->sb_blocks) {
459 return AVERROR(ENOMEM);
460 }
461 viv->n_sb_blocks = n_sb_blocks_tmp;
462
463 off = 0;
464 poff = 0;
465
466 for (i = 0; i < viv->n_sb_blocks; i++) {
467 uint64_t size_tmp = ffio_read_varlen(pb);
468 uint64_t n_packets_tmp = ffio_read_varlen(pb);
469
470 if (size_tmp > INT_MAX || n_packets_tmp > INT_MAX)
471 return AVERROR_INVALIDDATA;
472
473 viv->sb_blocks[i].byte_offset = off;
474 viv->sb_blocks[i].packet_offset = poff;
475
476 viv->sb_blocks[i].size = size_tmp;
477 viv->sb_blocks[i].n_packets = n_packets_tmp;
478
479 off += viv->sb_blocks[i].size;
480 poff += viv->sb_blocks[i].n_packets;
481
482 if (maxnp < viv->sb_blocks[i].n_packets)
483 maxnp = viv->sb_blocks[i].n_packets;
484 }
485
486 if (filesize > 0 && poff > filesize)
487 return AVERROR_INVALIDDATA;
488
489 viv->sb_entries = av_calloc(maxnp, sizeof(VIV_SB_entry));
490 if (!viv->sb_entries)
491 return AVERROR(ENOMEM);
492
493 return 0;
494 }
495
496 static void load_sb_block(AVFormatContext *s, VividasDemuxContext *viv, unsigned expected_size)
497 {
498 uint32_t size = 0;
499 int i;
500 AVIOContext *pb = 0;
501
502 if (viv->sb_pb) {
503 av_free(viv->sb_pb);
504 viv->sb_pb = NULL;
505 }
506
507 if (viv->sb_buf)
508 av_free(viv->sb_buf);
509
510 viv->sb_buf = read_sb_block(s->pb, &size, &viv->sb_key, expected_size);
511 if (!viv->sb_buf) {
512 return;
513 }
514
515 pb = avio_alloc_context(viv->sb_buf, size, 0, NULL, NULL, NULL, NULL);
516 if (!pb)
517 return;
518
519 viv->sb_pb = pb;
520
521 avio_r8(pb); // 'S'
522 avio_r8(pb); // 'B'
523 ffio_read_varlen(pb); // size
524 avio_r8(pb); // junk
525 ffio_read_varlen(pb); // first packet
526
527 viv->n_sb_entries = viv->sb_blocks[viv->current_sb].n_packets;
528
529 for (i = 0; i < viv->n_sb_entries; i++) {
530 viv->sb_entries[i].size = ffio_read_varlen(pb);
531 viv->sb_entries[i].flag = avio_r8(pb);
532 }
533
534 ffio_read_varlen(pb);
535 avio_r8(pb);
536
537 viv->current_sb_entry = 0;
538 }
539
540 static int viv_read_header(AVFormatContext *s)
541 {
542 VividasDemuxContext *viv = s->priv_data;
543 AVIOContext *pb = s->pb;
544 int64_t header_end;
545 int num_tracks;
546 uint32_t key, k2;
547 uint32_t v;
548 uint8_t keybuffer[187];
549 uint32_t b22_size = 0;
550 uint32_t b22_key = 0;
551 uint8_t *buf = 0;
552 int ret;
553
554 avio_skip(pb, 9);
555
556 header_end = avio_tell(pb);
557
558 header_end += ffio_read_varlen(pb);
559
560 num_tracks = avio_r8(pb);
561
562 if (num_tracks != 1) {
563 av_log(s, AV_LOG_ERROR, "number of tracks %d is not 1\n", num_tracks);
564 return AVERROR(EINVAL);
565 }
566
567 v = avio_r8(pb);
568 avio_seek(pb, v, SEEK_CUR);
569
570 avio_read(pb, keybuffer, 187);
571 key = decode_key(keybuffer);
572 viv->sb_key = key;
573
574 avio_rl32(pb);
575
576 for (;;) {
577 int64_t here = avio_tell(pb);
578 int block_len, block_type;
579
580 if (here >= header_end)
581 break;
582
583 block_len = ffio_read_varlen(pb);
584 if (avio_feof(pb) || block_len <= 0)
585 return AVERROR_INVALIDDATA;
586
587 block_type = avio_r8(pb);
588
589 if (block_type == 22) {
590 avio_read(pb, keybuffer, 187);
591 b22_key = decode_key(keybuffer);
592 b22_size = avio_rl32(pb);
593 }
594
595 avio_seek(pb, here + block_len, SEEK_SET);
596 }
597
598 if (b22_size) {
599 k2 = b22_key;
600 buf = read_vblock(pb, &v, b22_key, &k2, 0);
601 if (!buf)
602 return AVERROR(EIO);
603
604 av_free(buf);
605 }
606
607 k2 = key;
608 buf = read_vblock(pb, &v, key, &k2, 0);
609 if (!buf)
610 return AVERROR(EIO);
611 ret = track_header(viv, s, buf, v);
612 av_free(buf);
613 if (ret < 0)
614 return ret;
615
616 buf = read_vblock(pb, &v, key, &k2, v);
617 if (!buf)
618 return AVERROR(EIO);
619 ret = track_index(viv, s, buf, v);
620 av_free(buf);
621 if (ret < 0)
622 return ret;
623
624 viv->sb_offset = avio_tell(pb);
625 if (viv->n_sb_blocks > 0) {
626 viv->current_sb = 0;
627 load_sb_block(s, viv, viv->sb_blocks[0].size);
628 } else {
629 viv->current_sb = -1;
630 }
631
632 return 0;
633 }
634
635 static int viv_read_packet(AVFormatContext *s,
636 AVPacket *pkt)
637 {
638 VividasDemuxContext *viv = s->priv_data;
639 AVIOContext *pb;
640 int64_t off;
641 int ret;
642
643 if (!viv->sb_pb)
644 return AVERROR(EIO);
645 if (avio_feof(viv->sb_pb))
646 return AVERROR_EOF;
647
648 if (viv->current_audio_subpacket < viv->n_audio_subpackets) {
649 AVStream *astream;
650 int size = viv->audio_subpackets[viv->current_audio_subpacket+1].start - viv->audio_subpackets[viv->current_audio_subpacket].start;
651
652 pb = viv->sb_pb;
653 ret = av_get_packet(pb, pkt, size);
654 if (ret < 0)
655 return ret;
656 pkt->pos += viv->sb_offset + viv->sb_blocks[viv->current_sb].byte_offset;
657
658 pkt->stream_index = 1;
659 astream = s->streams[pkt->stream_index];
660
661 pkt->pts = av_rescale_q(viv->audio_sample, av_make_q(1, astream->codecpar->sample_rate), astream->time_base);
662 viv->audio_sample += viv->audio_subpackets[viv->current_audio_subpacket].pcm_bytes / 2 /
663 astream->codecpar->ch_layout.nb_channels;
664 pkt->flags |= AV_PKT_FLAG_KEY;
665 viv->current_audio_subpacket++;
666 return 0;
667 }
668
669 if (viv->current_sb_entry >= viv->n_sb_entries) {
670 if (viv->current_sb+1 >= viv->n_sb_blocks)
671 return AVERROR(EIO);
672 viv->current_sb++;
673
674 load_sb_block(s, viv, 0);
675 viv->current_sb_entry = 0;
676 }
677
678 pb = viv->sb_pb;
679 if (!pb)
680 return AVERROR(EIO);
681 off = avio_tell(pb);
682
683 if (viv->current_sb_entry >= viv->n_sb_entries)
684 return AVERROR_INVALIDDATA;
685
686 off += viv->sb_entries[viv->current_sb_entry].size;
687
688 if (viv->sb_entries[viv->current_sb_entry].flag == 0) {
689 uint64_t v_size = ffio_read_varlen(pb);
690 int last = 0, last_start;
691
692 if (!viv->num_audio)
693 return AVERROR_INVALIDDATA;
694
695 ffio_read_varlen(pb);
696 if (v_size > INT_MAX || !v_size)
697 return AVERROR_INVALIDDATA;
698 ret = av_get_packet(pb, pkt, v_size);
699 if (ret < 0)
700 return ret;
701 pkt->pos += viv->sb_offset + viv->sb_blocks[viv->current_sb].byte_offset;
702
703 pkt->pts = viv->sb_blocks[viv->current_sb].packet_offset + viv->current_sb_entry;
704 pkt->flags |= (pkt->data[0]&0x80)?0:AV_PKT_FLAG_KEY;
705 pkt->stream_index = 0;
706
707 for (int i = 0; i < MAX_AUDIO_SUBPACKETS - 1; i++) {
708 int start, pcm_bytes;
709 start = ffio_read_varlen(pb);
710 pcm_bytes = ffio_read_varlen(pb);
711
712 if (i > 0 && start == 0)
713 break;
714 if (start < last)
715 return AVERROR_INVALIDDATA;
716
717 viv->n_audio_subpackets = i + 1;
718 last =
719 viv->audio_subpackets[i].start = start;
720 viv->audio_subpackets[i].pcm_bytes = pcm_bytes;
721 }
722 last_start =
723 viv->audio_subpackets[viv->n_audio_subpackets].start = (int)(off - avio_tell(pb));
724 if (last_start < last)
725 return AVERROR_INVALIDDATA;
726 viv->current_audio_subpacket = 0;
727
728 } else {
729 uint64_t v_size = ffio_read_varlen(pb);
730
731 if (v_size > INT_MAX || !v_size)
732 return AVERROR_INVALIDDATA;
733 ret = av_get_packet(pb, pkt, v_size);
734 if (ret < 0)
735 return ret;
736 pkt->pos += viv->sb_offset + viv->sb_blocks[viv->current_sb].byte_offset;
737 pkt->pts = viv->sb_blocks[viv->current_sb].packet_offset + viv->current_sb_entry;
738 pkt->flags |= (pkt->data[0] & 0x80) ? 0 : AV_PKT_FLAG_KEY;
739 pkt->stream_index = 0;
740 }
741
742 viv->current_sb_entry++;
743
744 return 0;
745 }
746
747 static int viv_read_close(AVFormatContext *s)
748 {
749 VividasDemuxContext *viv = s->priv_data;
750
751 av_freep(&viv->sb_pb);
752 av_freep(&viv->sb_buf);
753 av_freep(&viv->sb_blocks);
754 av_freep(&viv->sb_entries);
755
756 return 0;
757 }
758
759 static int viv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
760 {
761 VividasDemuxContext *viv = s->priv_data;
762 int64_t frame;
763
764 if (stream_index == 0)
765 frame = timestamp;
766 else
767 frame = av_rescale_q(timestamp, s->streams[0]->time_base, s->streams[stream_index]->time_base);
768
769 for (int i = 0; i < viv->n_sb_blocks; i++) {
770 if (frame >= viv->sb_blocks[i].packet_offset && frame < viv->sb_blocks[i].packet_offset + viv->sb_blocks[i].n_packets) {
771 viv->current_sb = i;
772 // seek to ith sb block
773 avio_seek(s->pb, viv->sb_offset + viv->sb_blocks[i].byte_offset, SEEK_SET);
774 // load the block
775 load_sb_block(s, viv, 0);
776 if (viv->num_audio) {
777 const AVCodecParameters *par = s->streams[1]->codecpar;
778 // flush audio packet queue
779 viv->current_audio_subpacket = 0;
780 viv->n_audio_subpackets = 0;
781 // most problematic part: guess audio offset
782 viv->audio_sample = av_rescale_q(viv->sb_blocks[i].packet_offset,
783 av_make_q(par->sample_rate, 1),
784 av_inv_q(s->streams[0]->time_base));
785 // hand-tuned 1.s a/v offset
786 viv->audio_sample += par->sample_rate;
787 }
788 viv->current_sb_entry = 0;
789 return 1;
790 }
791 }
792 return 0;
793 }
794
795 const FFInputFormat ff_vividas_demuxer = {
796 .p.name = "vividas",
797 .p.long_name = NULL_IF_CONFIG_SMALL("Vividas VIV"),
798 .priv_data_size = sizeof(VividasDemuxContext),
799 .flags_internal = FF_INFMT_FLAG_INIT_CLEANUP,
800 .read_probe = viv_probe,
801 .read_header = viv_read_header,
802 .read_packet = viv_read_packet,
803 .read_close = viv_read_close,
804 .read_seek = viv_read_seek,
805 };
806