1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include <assert.h>
12 #include <limits.h>
13 #include <stdio.h>
14
15 #include "./vp9_rtcd.h"
16 #include "./vpx_dsp_rtcd.h"
17 #include "./vpx_scale_rtcd.h"
18
19 #include "vpx_mem/vpx_mem.h"
20 #include "vpx_ports/system_state.h"
21 #include "vpx_ports/vpx_once.h"
22 #include "vpx_ports/vpx_timer.h"
23 #include "vpx_scale/vpx_scale.h"
24 #include "vpx_util/vpx_thread.h"
25
26 #include "vp9/common/vp9_alloccommon.h"
27 #include "vp9/common/vp9_loopfilter.h"
28 #include "vp9/common/vp9_onyxc_int.h"
29 #if CONFIG_VP9_POSTPROC
30 #include "vp9/common/vp9_postproc.h"
31 #endif
32 #include "vp9/common/vp9_quant_common.h"
33 #include "vp9/common/vp9_reconintra.h"
34
35 #include "vp9/decoder/vp9_decodeframe.h"
36 #include "vp9/decoder/vp9_decoder.h"
37 #include "vp9/decoder/vp9_detokenize.h"
38
initialize_dec(void)39 static void initialize_dec(void) {
40 static volatile int init_done = 0;
41
42 if (!init_done) {
43 vp9_rtcd();
44 vpx_dsp_rtcd();
45 vpx_scale_rtcd();
46 vp9_init_intra_predictors();
47 init_done = 1;
48 }
49 }
50
vp9_dec_setup_mi(VP9_COMMON * cm)51 static void vp9_dec_setup_mi(VP9_COMMON *cm) {
52 cm->mi = cm->mip + cm->mi_stride + 1;
53 cm->mi_grid_visible = cm->mi_grid_base + cm->mi_stride + 1;
54 memset(cm->mi_grid_base, 0,
55 cm->mi_stride * (cm->mi_rows + 1) * sizeof(*cm->mi_grid_base));
56 }
57
vp9_dec_alloc_row_mt_mem(RowMTWorkerData * row_mt_worker_data,VP9_COMMON * cm,int num_sbs,int max_threads,int num_jobs)58 void vp9_dec_alloc_row_mt_mem(RowMTWorkerData *row_mt_worker_data,
59 VP9_COMMON *cm, int num_sbs, int max_threads,
60 int num_jobs) {
61 int plane;
62 const size_t dqcoeff_size = (num_sbs << DQCOEFFS_PER_SB_LOG2) *
63 sizeof(*row_mt_worker_data->dqcoeff[0]);
64 row_mt_worker_data->num_jobs = num_jobs;
65 #if CONFIG_MULTITHREAD
66 {
67 int i;
68 CHECK_MEM_ERROR(
69 cm, row_mt_worker_data->recon_sync_mutex,
70 vpx_malloc(sizeof(*row_mt_worker_data->recon_sync_mutex) * num_jobs));
71 if (row_mt_worker_data->recon_sync_mutex) {
72 for (i = 0; i < num_jobs; ++i) {
73 pthread_mutex_init(&row_mt_worker_data->recon_sync_mutex[i], NULL);
74 }
75 }
76
77 CHECK_MEM_ERROR(
78 cm, row_mt_worker_data->recon_sync_cond,
79 vpx_malloc(sizeof(*row_mt_worker_data->recon_sync_cond) * num_jobs));
80 if (row_mt_worker_data->recon_sync_cond) {
81 for (i = 0; i < num_jobs; ++i) {
82 pthread_cond_init(&row_mt_worker_data->recon_sync_cond[i], NULL);
83 }
84 }
85 }
86 #endif
87 row_mt_worker_data->num_sbs = num_sbs;
88 for (plane = 0; plane < 3; ++plane) {
89 CHECK_MEM_ERROR(cm, row_mt_worker_data->dqcoeff[plane],
90 vpx_memalign(16, dqcoeff_size));
91 memset(row_mt_worker_data->dqcoeff[plane], 0, dqcoeff_size);
92 CHECK_MEM_ERROR(cm, row_mt_worker_data->eob[plane],
93 vpx_calloc(num_sbs << EOBS_PER_SB_LOG2,
94 sizeof(*row_mt_worker_data->eob[plane])));
95 }
96 CHECK_MEM_ERROR(cm, row_mt_worker_data->partition,
97 vpx_calloc(num_sbs * PARTITIONS_PER_SB,
98 sizeof(*row_mt_worker_data->partition)));
99 CHECK_MEM_ERROR(cm, row_mt_worker_data->recon_map,
100 vpx_calloc(num_sbs, sizeof(*row_mt_worker_data->recon_map)));
101
102 // allocate memory for thread_data
103 if (row_mt_worker_data->thread_data == NULL) {
104 const size_t thread_size =
105 max_threads * sizeof(*row_mt_worker_data->thread_data);
106 CHECK_MEM_ERROR(cm, row_mt_worker_data->thread_data,
107 vpx_memalign(32, thread_size));
108 }
109 }
110
vp9_dec_free_row_mt_mem(RowMTWorkerData * row_mt_worker_data)111 void vp9_dec_free_row_mt_mem(RowMTWorkerData *row_mt_worker_data) {
112 if (row_mt_worker_data != NULL) {
113 int plane;
114 #if CONFIG_MULTITHREAD
115 int i;
116 if (row_mt_worker_data->recon_sync_mutex != NULL) {
117 for (i = 0; i < row_mt_worker_data->num_jobs; ++i) {
118 pthread_mutex_destroy(&row_mt_worker_data->recon_sync_mutex[i]);
119 }
120 vpx_free(row_mt_worker_data->recon_sync_mutex);
121 row_mt_worker_data->recon_sync_mutex = NULL;
122 }
123 if (row_mt_worker_data->recon_sync_cond != NULL) {
124 for (i = 0; i < row_mt_worker_data->num_jobs; ++i) {
125 pthread_cond_destroy(&row_mt_worker_data->recon_sync_cond[i]);
126 }
127 vpx_free(row_mt_worker_data->recon_sync_cond);
128 row_mt_worker_data->recon_sync_cond = NULL;
129 }
130 #endif
131 for (plane = 0; plane < 3; ++plane) {
132 vpx_free(row_mt_worker_data->eob[plane]);
133 row_mt_worker_data->eob[plane] = NULL;
134 vpx_free(row_mt_worker_data->dqcoeff[plane]);
135 row_mt_worker_data->dqcoeff[plane] = NULL;
136 }
137 vpx_free(row_mt_worker_data->partition);
138 row_mt_worker_data->partition = NULL;
139 vpx_free(row_mt_worker_data->recon_map);
140 row_mt_worker_data->recon_map = NULL;
141 vpx_free(row_mt_worker_data->thread_data);
142 row_mt_worker_data->thread_data = NULL;
143 }
144 }
145
vp9_dec_alloc_mi(VP9_COMMON * cm,int mi_size)146 static int vp9_dec_alloc_mi(VP9_COMMON *cm, int mi_size) {
147 cm->mip = vpx_calloc(mi_size, sizeof(*cm->mip));
148 if (!cm->mip) return 1;
149 cm->mi_alloc_size = mi_size;
150 cm->mi_grid_base = (MODE_INFO **)vpx_calloc(mi_size, sizeof(MODE_INFO *));
151 if (!cm->mi_grid_base) return 1;
152 return 0;
153 }
154
vp9_dec_free_mi(VP9_COMMON * cm)155 static void vp9_dec_free_mi(VP9_COMMON *cm) {
156 vpx_free(cm->mip);
157 cm->mip = NULL;
158 vpx_free(cm->mi_grid_base);
159 cm->mi_grid_base = NULL;
160 cm->mi_alloc_size = 0;
161 }
162
vp9_decoder_create(BufferPool * const pool)163 VP9Decoder *vp9_decoder_create(BufferPool *const pool) {
164 VP9Decoder *volatile const pbi = vpx_memalign(32, sizeof(*pbi));
165 VP9_COMMON *volatile const cm = pbi ? &pbi->common : NULL;
166
167 if (!cm) return NULL;
168
169 vp9_zero(*pbi);
170
171 if (setjmp(cm->error.jmp)) {
172 cm->error.setjmp = 0;
173 vp9_decoder_remove(pbi);
174 return NULL;
175 }
176
177 cm->error.setjmp = 1;
178
179 CHECK_MEM_ERROR(cm, cm->fc, (FRAME_CONTEXT *)vpx_calloc(1, sizeof(*cm->fc)));
180 CHECK_MEM_ERROR(
181 cm, cm->frame_contexts,
182 (FRAME_CONTEXT *)vpx_calloc(FRAME_CONTEXTS, sizeof(*cm->frame_contexts)));
183
184 pbi->need_resync = 1;
185 once(initialize_dec);
186
187 // Initialize the references to not point to any frame buffers.
188 memset(&cm->ref_frame_map, -1, sizeof(cm->ref_frame_map));
189 memset(&cm->next_ref_frame_map, -1, sizeof(cm->next_ref_frame_map));
190
191 cm->current_video_frame = 0;
192 pbi->ready_for_new_data = 1;
193 pbi->common.buffer_pool = pool;
194
195 cm->bit_depth = VPX_BITS_8;
196 cm->dequant_bit_depth = VPX_BITS_8;
197
198 cm->alloc_mi = vp9_dec_alloc_mi;
199 cm->free_mi = vp9_dec_free_mi;
200 cm->setup_mi = vp9_dec_setup_mi;
201
202 vp9_loop_filter_init(cm);
203
204 cm->error.setjmp = 0;
205
206 vpx_get_worker_interface()->init(&pbi->lf_worker);
207
208 return pbi;
209 }
210
vp9_decoder_remove(VP9Decoder * pbi)211 void vp9_decoder_remove(VP9Decoder *pbi) {
212 int i;
213
214 if (!pbi) return;
215
216 vpx_get_worker_interface()->end(&pbi->lf_worker);
217 vpx_free(pbi->lf_worker.data1);
218
219 for (i = 0; i < pbi->num_tile_workers; ++i) {
220 VPxWorker *const worker = &pbi->tile_workers[i];
221 vpx_get_worker_interface()->end(worker);
222 }
223
224 vpx_free(pbi->tile_worker_data);
225 vpx_free(pbi->tile_workers);
226
227 if (pbi->num_tile_workers > 0) {
228 vp9_loop_filter_dealloc(&pbi->lf_row_sync);
229 }
230
231 if (pbi->row_mt == 1) {
232 vp9_dec_free_row_mt_mem(pbi->row_mt_worker_data);
233 if (pbi->row_mt_worker_data != NULL) {
234 vp9_jobq_deinit(&pbi->row_mt_worker_data->jobq);
235 vpx_free(pbi->row_mt_worker_data->jobq_buf);
236 #if CONFIG_MULTITHREAD
237 pthread_mutex_destroy(&pbi->row_mt_worker_data->recon_done_mutex);
238 #endif
239 }
240 vpx_free(pbi->row_mt_worker_data);
241 }
242
243 vp9_remove_common(&pbi->common);
244 vpx_free(pbi);
245 }
246
equal_dimensions(const YV12_BUFFER_CONFIG * a,const YV12_BUFFER_CONFIG * b)247 static int equal_dimensions(const YV12_BUFFER_CONFIG *a,
248 const YV12_BUFFER_CONFIG *b) {
249 return a->y_height == b->y_height && a->y_width == b->y_width &&
250 a->uv_height == b->uv_height && a->uv_width == b->uv_width;
251 }
252
vp9_copy_reference_dec(VP9Decoder * pbi,VP9_REFFRAME ref_frame_flag,YV12_BUFFER_CONFIG * sd)253 vpx_codec_err_t vp9_copy_reference_dec(VP9Decoder *pbi,
254 VP9_REFFRAME ref_frame_flag,
255 YV12_BUFFER_CONFIG *sd) {
256 VP9_COMMON *cm = &pbi->common;
257
258 /* TODO(jkoleszar): The decoder doesn't have any real knowledge of what the
259 * encoder is using the frame buffers for. This is just a stub to keep the
260 * vpxenc --test-decode functionality working, and will be replaced in a
261 * later commit that adds VP9-specific controls for this functionality.
262 */
263 if (ref_frame_flag == VP9_LAST_FLAG) {
264 const YV12_BUFFER_CONFIG *const cfg = get_ref_frame(cm, 0);
265 if (cfg == NULL) {
266 vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
267 "No 'last' reference frame");
268 return VPX_CODEC_ERROR;
269 }
270 if (!equal_dimensions(cfg, sd))
271 vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
272 "Incorrect buffer dimensions");
273 else
274 vpx_yv12_copy_frame(cfg, sd);
275 } else {
276 vpx_internal_error(&cm->error, VPX_CODEC_ERROR, "Invalid reference frame");
277 }
278
279 return cm->error.error_code;
280 }
281
vp9_set_reference_dec(VP9_COMMON * cm,VP9_REFFRAME ref_frame_flag,YV12_BUFFER_CONFIG * sd)282 vpx_codec_err_t vp9_set_reference_dec(VP9_COMMON *cm,
283 VP9_REFFRAME ref_frame_flag,
284 YV12_BUFFER_CONFIG *sd) {
285 int idx;
286 YV12_BUFFER_CONFIG *ref_buf = NULL;
287
288 // TODO(jkoleszar): The decoder doesn't have any real knowledge of what the
289 // encoder is using the frame buffers for. This is just a stub to keep the
290 // vpxenc --test-decode functionality working, and will be replaced in a
291 // later commit that adds VP9-specific controls for this functionality.
292 // (Yunqing) The set_reference control depends on the following setting in
293 // encoder.
294 // cpi->lst_fb_idx = 0;
295 // cpi->gld_fb_idx = 1;
296 // cpi->alt_fb_idx = 2;
297 if (ref_frame_flag == VP9_LAST_FLAG) {
298 idx = cm->ref_frame_map[0];
299 } else if (ref_frame_flag == VP9_GOLD_FLAG) {
300 idx = cm->ref_frame_map[1];
301 } else if (ref_frame_flag == VP9_ALT_FLAG) {
302 idx = cm->ref_frame_map[2];
303 } else {
304 vpx_internal_error(&cm->error, VPX_CODEC_ERROR, "Invalid reference frame");
305 return cm->error.error_code;
306 }
307
308 if (idx < 0 || idx >= FRAME_BUFFERS) {
309 vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
310 "Invalid reference frame map");
311 return cm->error.error_code;
312 }
313
314 // Get the destination reference buffer.
315 ref_buf = &cm->buffer_pool->frame_bufs[idx].buf;
316
317 if (!equal_dimensions(ref_buf, sd)) {
318 vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
319 "Incorrect buffer dimensions");
320 } else {
321 // Overwrite the reference frame buffer.
322 vpx_yv12_copy_frame(sd, ref_buf);
323 }
324
325 return cm->error.error_code;
326 }
327
328 /* If any buffer updating is signaled it should be done here. */
swap_frame_buffers(VP9Decoder * pbi)329 static void swap_frame_buffers(VP9Decoder *pbi) {
330 int ref_index = 0, mask;
331 VP9_COMMON *const cm = &pbi->common;
332 BufferPool *const pool = cm->buffer_pool;
333 RefCntBuffer *const frame_bufs = cm->buffer_pool->frame_bufs;
334
335 for (mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
336 const int old_idx = cm->ref_frame_map[ref_index];
337 // Current thread releases the holding of reference frame.
338 decrease_ref_count(old_idx, frame_bufs, pool);
339
340 // Release the reference frame in reference map.
341 if (mask & 1) {
342 decrease_ref_count(old_idx, frame_bufs, pool);
343 }
344 cm->ref_frame_map[ref_index] = cm->next_ref_frame_map[ref_index];
345 ++ref_index;
346 }
347
348 // Current thread releases the holding of reference frame.
349 for (; ref_index < REF_FRAMES && !cm->show_existing_frame; ++ref_index) {
350 const int old_idx = cm->ref_frame_map[ref_index];
351 decrease_ref_count(old_idx, frame_bufs, pool);
352 cm->ref_frame_map[ref_index] = cm->next_ref_frame_map[ref_index];
353 }
354 pbi->hold_ref_buf = 0;
355 cm->frame_to_show = get_frame_new_buffer(cm);
356
357 --frame_bufs[cm->new_fb_idx].ref_count;
358
359 // Invalidate these references until the next frame starts.
360 for (ref_index = 0; ref_index < 3; ref_index++)
361 cm->frame_refs[ref_index].idx = -1;
362 }
363
release_fb_on_decoder_exit(VP9Decoder * pbi)364 static void release_fb_on_decoder_exit(VP9Decoder *pbi) {
365 const VPxWorkerInterface *const winterface = vpx_get_worker_interface();
366 VP9_COMMON *volatile const cm = &pbi->common;
367 BufferPool *volatile const pool = cm->buffer_pool;
368 RefCntBuffer *volatile const frame_bufs = cm->buffer_pool->frame_bufs;
369 int i;
370
371 // Synchronize all threads immediately as a subsequent decode call may
372 // cause a resize invalidating some allocations.
373 winterface->sync(&pbi->lf_worker);
374 for (i = 0; i < pbi->num_tile_workers; ++i) {
375 winterface->sync(&pbi->tile_workers[i]);
376 }
377
378 // Release all the reference buffers if worker thread is holding them.
379 if (pbi->hold_ref_buf == 1) {
380 int ref_index = 0, mask;
381 for (mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
382 const int old_idx = cm->ref_frame_map[ref_index];
383 // Current thread releases the holding of reference frame.
384 decrease_ref_count(old_idx, frame_bufs, pool);
385
386 // Release the reference frame in reference map.
387 if (mask & 1) {
388 decrease_ref_count(old_idx, frame_bufs, pool);
389 }
390 ++ref_index;
391 }
392
393 // Current thread releases the holding of reference frame.
394 for (; ref_index < REF_FRAMES && !cm->show_existing_frame; ++ref_index) {
395 const int old_idx = cm->ref_frame_map[ref_index];
396 decrease_ref_count(old_idx, frame_bufs, pool);
397 }
398 pbi->hold_ref_buf = 0;
399 }
400 }
401
vp9_receive_compressed_data(VP9Decoder * pbi,size_t size,const uint8_t ** psource)402 int vp9_receive_compressed_data(VP9Decoder *pbi, size_t size,
403 const uint8_t **psource) {
404 VP9_COMMON *volatile const cm = &pbi->common;
405 BufferPool *volatile const pool = cm->buffer_pool;
406 RefCntBuffer *volatile const frame_bufs = cm->buffer_pool->frame_bufs;
407 const uint8_t *source = *psource;
408 int retcode = 0;
409 cm->error.error_code = VPX_CODEC_OK;
410
411 if (size == 0) {
412 // This is used to signal that we are missing frames.
413 // We do not know if the missing frame(s) was supposed to update
414 // any of the reference buffers, but we act conservative and
415 // mark only the last buffer as corrupted.
416 //
417 // TODO(jkoleszar): Error concealment is undefined and non-normative
418 // at this point, but if it becomes so, [0] may not always be the correct
419 // thing to do here.
420 if (cm->frame_refs[0].idx > 0) {
421 assert(cm->frame_refs[0].buf != NULL);
422 cm->frame_refs[0].buf->corrupted = 1;
423 }
424 }
425
426 pbi->ready_for_new_data = 0;
427
428 // Check if the previous frame was a frame without any references to it.
429 if (cm->new_fb_idx >= 0 && frame_bufs[cm->new_fb_idx].ref_count == 0 &&
430 !frame_bufs[cm->new_fb_idx].released) {
431 pool->release_fb_cb(pool->cb_priv,
432 &frame_bufs[cm->new_fb_idx].raw_frame_buffer);
433 frame_bufs[cm->new_fb_idx].released = 1;
434 }
435
436 // Find a free frame buffer. Return error if can not find any.
437 cm->new_fb_idx = get_free_fb(cm);
438 if (cm->new_fb_idx == INVALID_IDX) {
439 pbi->ready_for_new_data = 1;
440 release_fb_on_decoder_exit(pbi);
441 vpx_clear_system_state();
442 vpx_internal_error(&cm->error, VPX_CODEC_MEM_ERROR,
443 "Unable to find free frame buffer");
444 return cm->error.error_code;
445 }
446
447 // Assign a MV array to the frame buffer.
448 cm->cur_frame = &pool->frame_bufs[cm->new_fb_idx];
449
450 pbi->hold_ref_buf = 0;
451 pbi->cur_buf = &frame_bufs[cm->new_fb_idx];
452
453 if (setjmp(cm->error.jmp)) {
454 cm->error.setjmp = 0;
455 pbi->ready_for_new_data = 1;
456 release_fb_on_decoder_exit(pbi);
457 // Release current frame.
458 decrease_ref_count(cm->new_fb_idx, frame_bufs, pool);
459 vpx_clear_system_state();
460 return -1;
461 }
462
463 cm->error.setjmp = 1;
464 vp9_decode_frame(pbi, source, source + size, psource);
465
466 swap_frame_buffers(pbi);
467
468 vpx_clear_system_state();
469
470 if (!cm->show_existing_frame) {
471 cm->last_show_frame = cm->show_frame;
472 cm->prev_frame = cm->cur_frame;
473 if (cm->seg.enabled) vp9_swap_current_and_last_seg_map(cm);
474 }
475
476 if (cm->show_frame) cm->cur_show_frame_fb_idx = cm->new_fb_idx;
477
478 // Update progress in frame parallel decode.
479 cm->last_width = cm->width;
480 cm->last_height = cm->height;
481 if (cm->show_frame) {
482 cm->current_video_frame++;
483 }
484
485 cm->error.setjmp = 0;
486 return retcode;
487 }
488
vp9_get_raw_frame(VP9Decoder * pbi,YV12_BUFFER_CONFIG * sd,vp9_ppflags_t * flags)489 int vp9_get_raw_frame(VP9Decoder *pbi, YV12_BUFFER_CONFIG *sd,
490 vp9_ppflags_t *flags) {
491 VP9_COMMON *const cm = &pbi->common;
492 int ret = -1;
493 #if !CONFIG_VP9_POSTPROC
494 (void)*flags;
495 #endif
496
497 if (pbi->ready_for_new_data == 1) return ret;
498
499 pbi->ready_for_new_data = 1;
500
501 /* no raw frame to show!!! */
502 if (!cm->show_frame) return ret;
503
504 pbi->ready_for_new_data = 1;
505
506 #if CONFIG_VP9_POSTPROC
507 if (!cm->show_existing_frame) {
508 ret = vp9_post_proc_frame(cm, sd, flags, cm->width);
509 } else {
510 *sd = *cm->frame_to_show;
511 ret = 0;
512 }
513 #else
514 *sd = *cm->frame_to_show;
515 ret = 0;
516 #endif /*!CONFIG_POSTPROC*/
517 vpx_clear_system_state();
518 return ret;
519 }
520
vp9_parse_superframe_index(const uint8_t * data,size_t data_sz,uint32_t sizes[8],int * count,vpx_decrypt_cb decrypt_cb,void * decrypt_state)521 vpx_codec_err_t vp9_parse_superframe_index(const uint8_t *data, size_t data_sz,
522 uint32_t sizes[8], int *count,
523 vpx_decrypt_cb decrypt_cb,
524 void *decrypt_state) {
525 // A chunk ending with a byte matching 0xc0 is an invalid chunk unless
526 // it is a super frame index. If the last byte of real video compression
527 // data is 0xc0 the encoder must add a 0 byte. If we have the marker but
528 // not the associated matching marker byte at the front of the index we have
529 // an invalid bitstream and need to return an error.
530
531 uint8_t marker;
532
533 assert(data_sz);
534 marker = read_marker(decrypt_cb, decrypt_state, data + data_sz - 1);
535 *count = 0;
536
537 if ((marker & 0xe0) == 0xc0) {
538 const uint32_t frames = (marker & 0x7) + 1;
539 const uint32_t mag = ((marker >> 3) & 0x3) + 1;
540 const size_t index_sz = 2 + mag * frames;
541
542 // This chunk is marked as having a superframe index but doesn't have
543 // enough data for it, thus it's an invalid superframe index.
544 if (data_sz < index_sz) return VPX_CODEC_CORRUPT_FRAME;
545
546 {
547 const uint8_t marker2 =
548 read_marker(decrypt_cb, decrypt_state, data + data_sz - index_sz);
549
550 // This chunk is marked as having a superframe index but doesn't have
551 // the matching marker byte at the front of the index therefore it's an
552 // invalid chunk.
553 if (marker != marker2) return VPX_CODEC_CORRUPT_FRAME;
554 }
555
556 {
557 // Found a valid superframe index.
558 uint32_t i, j;
559 const uint8_t *x = &data[data_sz - index_sz + 1];
560
561 // Frames has a maximum of 8 and mag has a maximum of 4.
562 uint8_t clear_buffer[32];
563 assert(sizeof(clear_buffer) >= frames * mag);
564 if (decrypt_cb) {
565 decrypt_cb(decrypt_state, x, clear_buffer, frames * mag);
566 x = clear_buffer;
567 }
568
569 for (i = 0; i < frames; ++i) {
570 uint32_t this_sz = 0;
571
572 for (j = 0; j < mag; ++j) this_sz |= ((uint32_t)(*x++)) << (j * 8);
573 sizes[i] = this_sz;
574 }
575 *count = frames;
576 }
577 }
578 return VPX_CODEC_OK;
579 }
580