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