1 /*
2 * H.264/HEVC common parsing code
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include <string.h>
22
23 #include "config.h"
24
25 #include "libavutil/intmath.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/mem.h"
28
29 #include "bytestream.h"
30 #include "hevc.h"
31 #include "h264.h"
32 #include "h2645_parse.h"
33
ff_h2645_extract_rbsp(const uint8_t * src,int length,H2645RBSP * rbsp,H2645NAL * nal,int small_padding)34 int ff_h2645_extract_rbsp(const uint8_t *src, int length,
35 H2645RBSP *rbsp, H2645NAL *nal, int small_padding)
36 {
37 int i, si, di;
38 uint8_t *dst;
39
40 nal->skipped_bytes = 0;
41 #define STARTCODE_TEST \
42 if (i + 2 < length && src[i + 1] == 0 && src[i + 2] <= 3) { \
43 if (src[i + 2] != 3 && src[i + 2] != 0) { \
44 /* startcode, so we must be past the end */ \
45 length = i; \
46 } \
47 break; \
48 }
49 #if HAVE_FAST_UNALIGNED
50 #define FIND_FIRST_ZERO \
51 if (i > 0 && !src[i]) \
52 i--; \
53 while (src[i]) \
54 i++
55 #if HAVE_FAST_64BIT
56 for (i = 0; i + 1 < length; i += 9) {
57 if (!((~AV_RN64(src + i) &
58 (AV_RN64(src + i) - 0x0100010001000101ULL)) &
59 0x8000800080008080ULL))
60 continue;
61 FIND_FIRST_ZERO;
62 STARTCODE_TEST;
63 i -= 7;
64 }
65 #else
66 for (i = 0; i + 1 < length; i += 5) {
67 if (!((~AV_RN32(src + i) &
68 (AV_RN32(src + i) - 0x01000101U)) &
69 0x80008080U))
70 continue;
71 FIND_FIRST_ZERO;
72 STARTCODE_TEST;
73 i -= 3;
74 }
75 #endif /* HAVE_FAST_64BIT */
76 #else
77 for (i = 0; i + 1 < length; i += 2) {
78 if (src[i])
79 continue;
80 if (i > 0 && src[i - 1] == 0)
81 i--;
82 STARTCODE_TEST;
83 }
84 #endif /* HAVE_FAST_UNALIGNED */
85
86 if (i >= length - 1 && small_padding) { // no escaped 0
87 nal->data =
88 nal->raw_data = src;
89 nal->size =
90 nal->raw_size = length;
91 return length;
92 } else if (i > length)
93 i = length;
94
95 dst = &rbsp->rbsp_buffer[rbsp->rbsp_buffer_size];
96
97 memcpy(dst, src, i);
98 si = di = i;
99 while (si + 2 < length) {
100 // remove escapes (very rare 1:2^22)
101 if (src[si + 2] > 3) {
102 dst[di++] = src[si++];
103 dst[di++] = src[si++];
104 } else if (src[si] == 0 && src[si + 1] == 0 && src[si + 2] != 0) {
105 if (src[si + 2] == 3) { // escape
106 dst[di++] = 0;
107 dst[di++] = 0;
108 si += 3;
109
110 if (nal->skipped_bytes_pos) {
111 nal->skipped_bytes++;
112 if (nal->skipped_bytes_pos_size < nal->skipped_bytes) {
113 nal->skipped_bytes_pos_size *= 2;
114 av_assert0(nal->skipped_bytes_pos_size >= nal->skipped_bytes);
115 av_reallocp_array(&nal->skipped_bytes_pos,
116 nal->skipped_bytes_pos_size,
117 sizeof(*nal->skipped_bytes_pos));
118 if (!nal->skipped_bytes_pos) {
119 nal->skipped_bytes_pos_size = 0;
120 return AVERROR(ENOMEM);
121 }
122 }
123 if (nal->skipped_bytes_pos)
124 nal->skipped_bytes_pos[nal->skipped_bytes-1] = di - 1;
125 }
126 continue;
127 } else // next start code
128 goto nsc;
129 }
130
131 dst[di++] = src[si++];
132 }
133 while (si < length)
134 dst[di++] = src[si++];
135
136 nsc:
137 memset(dst + di, 0, AV_INPUT_BUFFER_PADDING_SIZE);
138
139 nal->data = dst;
140 nal->size = di;
141 nal->raw_data = src;
142 nal->raw_size = si;
143 rbsp->rbsp_buffer_size += si;
144
145 return si;
146 }
147
148 static const char *const hevc_nal_type_name[64] = {
149 "TRAIL_N", // HEVC_NAL_TRAIL_N
150 "TRAIL_R", // HEVC_NAL_TRAIL_R
151 "TSA_N", // HEVC_NAL_TSA_N
152 "TSA_R", // HEVC_NAL_TSA_R
153 "STSA_N", // HEVC_NAL_STSA_N
154 "STSA_R", // HEVC_NAL_STSA_R
155 "RADL_N", // HEVC_NAL_RADL_N
156 "RADL_R", // HEVC_NAL_RADL_R
157 "RASL_N", // HEVC_NAL_RASL_N
158 "RASL_R", // HEVC_NAL_RASL_R
159 "RSV_VCL_N10", // HEVC_NAL_VCL_N10
160 "RSV_VCL_R11", // HEVC_NAL_VCL_R11
161 "RSV_VCL_N12", // HEVC_NAL_VCL_N12
162 "RSV_VLC_R13", // HEVC_NAL_VCL_R13
163 "RSV_VCL_N14", // HEVC_NAL_VCL_N14
164 "RSV_VCL_R15", // HEVC_NAL_VCL_R15
165 "BLA_W_LP", // HEVC_NAL_BLA_W_LP
166 "BLA_W_RADL", // HEVC_NAL_BLA_W_RADL
167 "BLA_N_LP", // HEVC_NAL_BLA_N_LP
168 "IDR_W_RADL", // HEVC_NAL_IDR_W_RADL
169 "IDR_N_LP", // HEVC_NAL_IDR_N_LP
170 "CRA_NUT", // HEVC_NAL_CRA_NUT
171 "RSV_IRAP_VCL22", // HEVC_NAL_RSV_IRAP_VCL22
172 "RSV_IRAP_VCL23", // HEVC_NAL_RSV_IRAP_VCL23
173 "RSV_VCL24", // HEVC_NAL_RSV_VCL24
174 "RSV_VCL25", // HEVC_NAL_RSV_VCL25
175 "RSV_VCL26", // HEVC_NAL_RSV_VCL26
176 "RSV_VCL27", // HEVC_NAL_RSV_VCL27
177 "RSV_VCL28", // HEVC_NAL_RSV_VCL28
178 "RSV_VCL29", // HEVC_NAL_RSV_VCL29
179 "RSV_VCL30", // HEVC_NAL_RSV_VCL30
180 "RSV_VCL31", // HEVC_NAL_RSV_VCL31
181 "VPS", // HEVC_NAL_VPS
182 "SPS", // HEVC_NAL_SPS
183 "PPS", // HEVC_NAL_PPS
184 "AUD", // HEVC_NAL_AUD
185 "EOS_NUT", // HEVC_NAL_EOS_NUT
186 "EOB_NUT", // HEVC_NAL_EOB_NUT
187 "FD_NUT", // HEVC_NAL_FD_NUT
188 "SEI_PREFIX", // HEVC_NAL_SEI_PREFIX
189 "SEI_SUFFIX", // HEVC_NAL_SEI_SUFFIX
190 "RSV_NVCL41", // HEVC_NAL_RSV_NVCL41
191 "RSV_NVCL42", // HEVC_NAL_RSV_NVCL42
192 "RSV_NVCL43", // HEVC_NAL_RSV_NVCL43
193 "RSV_NVCL44", // HEVC_NAL_RSV_NVCL44
194 "RSV_NVCL45", // HEVC_NAL_RSV_NVCL45
195 "RSV_NVCL46", // HEVC_NAL_RSV_NVCL46
196 "RSV_NVCL47", // HEVC_NAL_RSV_NVCL47
197 "UNSPEC48", // HEVC_NAL_UNSPEC48
198 "UNSPEC49", // HEVC_NAL_UNSPEC49
199 "UNSPEC50", // HEVC_NAL_UNSPEC50
200 "UNSPEC51", // HEVC_NAL_UNSPEC51
201 "UNSPEC52", // HEVC_NAL_UNSPEC52
202 "UNSPEC53", // HEVC_NAL_UNSPEC53
203 "UNSPEC54", // HEVC_NAL_UNSPEC54
204 "UNSPEC55", // HEVC_NAL_UNSPEC55
205 "UNSPEC56", // HEVC_NAL_UNSPEC56
206 "UNSPEC57", // HEVC_NAL_UNSPEC57
207 "UNSPEC58", // HEVC_NAL_UNSPEC58
208 "UNSPEC59", // HEVC_NAL_UNSPEC59
209 "UNSPEC60", // HEVC_NAL_UNSPEC60
210 "UNSPEC61", // HEVC_NAL_UNSPEC61
211 "UNSPEC62", // HEVC_NAL_UNSPEC62
212 "UNSPEC63", // HEVC_NAL_UNSPEC63
213 };
214
hevc_nal_unit_name(int nal_type)215 static const char *hevc_nal_unit_name(int nal_type)
216 {
217 av_assert0(nal_type >= 0 && nal_type < 64);
218 return hevc_nal_type_name[nal_type];
219 }
220
221 static const char *const h264_nal_type_name[32] = {
222 "Unspecified 0", //H264_NAL_UNSPECIFIED
223 "Coded slice of a non-IDR picture", // H264_NAL_SLICE
224 "Coded slice data partition A", // H264_NAL_DPA
225 "Coded slice data partition B", // H264_NAL_DPB
226 "Coded slice data partition C", // H264_NAL_DPC
227 "IDR", // H264_NAL_IDR_SLICE
228 "SEI", // H264_NAL_SEI
229 "SPS", // H264_NAL_SPS
230 "PPS", // H264_NAL_PPS
231 "AUD", // H264_NAL_AUD
232 "End of sequence", // H264_NAL_END_SEQUENCE
233 "End of stream", // H264_NAL_END_STREAM
234 "Filler data", // H264_NAL_FILLER_DATA
235 "SPS extension", // H264_NAL_SPS_EXT
236 "Prefix", // H264_NAL_PREFIX
237 "Subset SPS", // H264_NAL_SUB_SPS
238 "Depth parameter set", // H264_NAL_DPS
239 "Reserved 17", // H264_NAL_RESERVED17
240 "Reserved 18", // H264_NAL_RESERVED18
241 "Auxiliary coded picture without partitioning", // H264_NAL_AUXILIARY_SLICE
242 "Slice extension", // H264_NAL_EXTEN_SLICE
243 "Slice extension for a depth view or a 3D-AVC texture view", // H264_NAL_DEPTH_EXTEN_SLICE
244 "Reserved 22", // H264_NAL_RESERVED22
245 "Reserved 23", // H264_NAL_RESERVED23
246 "Unspecified 24", // H264_NAL_UNSPECIFIED24
247 "Unspecified 25", // H264_NAL_UNSPECIFIED25
248 "Unspecified 26", // H264_NAL_UNSPECIFIED26
249 "Unspecified 27", // H264_NAL_UNSPECIFIED27
250 "Unspecified 28", // H264_NAL_UNSPECIFIED28
251 "Unspecified 29", // H264_NAL_UNSPECIFIED29
252 "Unspecified 30", // H264_NAL_UNSPECIFIED30
253 "Unspecified 31", // H264_NAL_UNSPECIFIED31
254 };
255
h264_nal_unit_name(int nal_type)256 static const char *h264_nal_unit_name(int nal_type)
257 {
258 av_assert0(nal_type >= 0 && nal_type < 32);
259 return h264_nal_type_name[nal_type];
260 }
261
get_bit_length(H2645NAL * nal,int min_size,int skip_trailing_zeros)262 static int get_bit_length(H2645NAL *nal, int min_size, int skip_trailing_zeros)
263 {
264 int size = nal->size;
265 int trailing_padding = 0;
266
267 while (skip_trailing_zeros && size > 0 && nal->data[size - 1] == 0)
268 size--;
269
270 if (!size)
271 return 0;
272
273 if (size <= min_size) {
274 if (nal->size < min_size)
275 return AVERROR_INVALIDDATA;
276 size = min_size;
277 } else {
278 int v = nal->data[size - 1];
279 /* remove the stop bit and following trailing zeros,
280 * or nothing for damaged bitstreams */
281 if (v)
282 trailing_padding = ff_ctz(v) + 1;
283 }
284
285 if (size > INT_MAX / 8)
286 return AVERROR(ERANGE);
287 size *= 8;
288
289 return size - trailing_padding;
290 }
291
292 /**
293 * @return AVERROR_INVALIDDATA if the packet is not a valid NAL unit,
294 * 0 otherwise
295 */
hevc_parse_nal_header(H2645NAL * nal,void * logctx)296 static int hevc_parse_nal_header(H2645NAL *nal, void *logctx)
297 {
298 GetBitContext *gb = &nal->gb;
299
300 if (get_bits1(gb) != 0)
301 return AVERROR_INVALIDDATA;
302
303 nal->type = get_bits(gb, 6);
304
305 nal->nuh_layer_id = get_bits(gb, 6);
306 nal->temporal_id = get_bits(gb, 3) - 1;
307 if (nal->temporal_id < 0)
308 return AVERROR_INVALIDDATA;
309
310 av_log(logctx, AV_LOG_DEBUG,
311 "nal_unit_type: %d(%s), nuh_layer_id: %d, temporal_id: %d\n",
312 nal->type, hevc_nal_unit_name(nal->type), nal->nuh_layer_id, nal->temporal_id);
313
314 return 0;
315 }
316
h264_parse_nal_header(H2645NAL * nal,void * logctx)317 static int h264_parse_nal_header(H2645NAL *nal, void *logctx)
318 {
319 GetBitContext *gb = &nal->gb;
320
321 if (get_bits1(gb) != 0)
322 return AVERROR_INVALIDDATA;
323
324 nal->ref_idc = get_bits(gb, 2);
325 nal->type = get_bits(gb, 5);
326
327 av_log(logctx, AV_LOG_DEBUG,
328 "nal_unit_type: %d(%s), nal_ref_idc: %d\n",
329 nal->type, h264_nal_unit_name(nal->type), nal->ref_idc);
330
331 return 0;
332 }
333
find_next_start_code(const uint8_t * buf,const uint8_t * next_avc)334 static int find_next_start_code(const uint8_t *buf, const uint8_t *next_avc)
335 {
336 int i = 0;
337
338 if (buf + 3 >= next_avc)
339 return next_avc - buf;
340
341 while (buf + i + 3 < next_avc) {
342 if (buf[i] == 0 && buf[i + 1] == 0 && buf[i + 2] == 1)
343 break;
344 i++;
345 }
346 return i + 3;
347 }
348
alloc_rbsp_buffer(H2645RBSP * rbsp,unsigned int size,int use_ref)349 static void alloc_rbsp_buffer(H2645RBSP *rbsp, unsigned int size, int use_ref)
350 {
351 int min_size = size;
352
353 if (size > INT_MAX - AV_INPUT_BUFFER_PADDING_SIZE)
354 goto fail;
355 size += AV_INPUT_BUFFER_PADDING_SIZE;
356
357 if (rbsp->rbsp_buffer_alloc_size >= size &&
358 (!rbsp->rbsp_buffer_ref || av_buffer_is_writable(rbsp->rbsp_buffer_ref))) {
359 av_assert0(rbsp->rbsp_buffer);
360 memset(rbsp->rbsp_buffer + min_size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
361 return;
362 }
363
364 size = FFMIN(size + size / 16 + 32, INT_MAX);
365
366 if (rbsp->rbsp_buffer_ref)
367 av_buffer_unref(&rbsp->rbsp_buffer_ref);
368 else
369 av_free(rbsp->rbsp_buffer);
370
371 rbsp->rbsp_buffer = av_mallocz(size);
372 if (!rbsp->rbsp_buffer)
373 goto fail;
374 rbsp->rbsp_buffer_alloc_size = size;
375
376 if (use_ref) {
377 rbsp->rbsp_buffer_ref = av_buffer_create(rbsp->rbsp_buffer, size,
378 NULL, NULL, 0);
379 if (!rbsp->rbsp_buffer_ref)
380 goto fail;
381 }
382
383 return;
384
385 fail:
386 rbsp->rbsp_buffer_alloc_size = 0;
387 if (rbsp->rbsp_buffer_ref) {
388 av_buffer_unref(&rbsp->rbsp_buffer_ref);
389 rbsp->rbsp_buffer = NULL;
390 } else
391 av_freep(&rbsp->rbsp_buffer);
392
393 return;
394 }
395
ff_h2645_packet_split(H2645Packet * pkt,const uint8_t * buf,int length,void * logctx,int is_nalff,int nal_length_size,enum AVCodecID codec_id,int small_padding,int use_ref)396 int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
397 void *logctx, int is_nalff, int nal_length_size,
398 enum AVCodecID codec_id, int small_padding, int use_ref)
399 {
400 GetByteContext bc;
401 int consumed, ret = 0;
402 int next_avc = is_nalff ? 0 : length;
403 int64_t padding = small_padding ? 0 : MAX_MBPAIR_SIZE;
404
405 bytestream2_init(&bc, buf, length);
406 alloc_rbsp_buffer(&pkt->rbsp, length + padding, use_ref);
407
408 if (!pkt->rbsp.rbsp_buffer)
409 return AVERROR(ENOMEM);
410
411 pkt->rbsp.rbsp_buffer_size = 0;
412 pkt->nb_nals = 0;
413 while (bytestream2_get_bytes_left(&bc) >= 4) {
414 H2645NAL *nal;
415 int extract_length = 0;
416 int skip_trailing_zeros = 1;
417
418 if (bytestream2_tell(&bc) == next_avc) {
419 int i = 0;
420 extract_length = get_nalsize(nal_length_size,
421 bc.buffer, bytestream2_get_bytes_left(&bc), &i, logctx);
422 if (extract_length < 0)
423 return extract_length;
424
425 bytestream2_skip(&bc, nal_length_size);
426
427 next_avc = bytestream2_tell(&bc) + extract_length;
428 } else {
429 int buf_index;
430
431 if (bytestream2_tell(&bc) > next_avc)
432 av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n");
433
434 /* search start code */
435 buf_index = find_next_start_code(bc.buffer, buf + next_avc);
436
437 bytestream2_skip(&bc, buf_index);
438
439 if (!bytestream2_get_bytes_left(&bc)) {
440 if (pkt->nb_nals > 0) {
441 // No more start codes: we discarded some irrelevant
442 // bytes at the end of the packet.
443 return 0;
444 } else {
445 av_log(logctx, AV_LOG_ERROR, "No start code is found.\n");
446 return AVERROR_INVALIDDATA;
447 }
448 }
449
450 extract_length = FFMIN(bytestream2_get_bytes_left(&bc), next_avc - bytestream2_tell(&bc));
451
452 if (bytestream2_tell(&bc) >= next_avc) {
453 /* skip to the start of the next NAL */
454 bytestream2_skip(&bc, next_avc - bytestream2_tell(&bc));
455 continue;
456 }
457 }
458
459 if (pkt->nals_allocated < pkt->nb_nals + 1) {
460 int new_size = pkt->nals_allocated + 1;
461 void *tmp;
462
463 if (new_size >= INT_MAX / sizeof(*pkt->nals))
464 return AVERROR(ENOMEM);
465
466 tmp = av_fast_realloc(pkt->nals, &pkt->nal_buffer_size, new_size * sizeof(*pkt->nals));
467 if (!tmp)
468 return AVERROR(ENOMEM);
469
470 pkt->nals = tmp;
471 memset(pkt->nals + pkt->nals_allocated, 0, sizeof(*pkt->nals));
472
473 nal = &pkt->nals[pkt->nb_nals];
474 nal->skipped_bytes_pos_size = FFMIN(1024, extract_length/3+1); // initial buffer size
475 nal->skipped_bytes_pos = av_malloc_array(nal->skipped_bytes_pos_size, sizeof(*nal->skipped_bytes_pos));
476 if (!nal->skipped_bytes_pos)
477 return AVERROR(ENOMEM);
478
479 pkt->nals_allocated = new_size;
480 }
481 nal = &pkt->nals[pkt->nb_nals];
482
483 consumed = ff_h2645_extract_rbsp(bc.buffer, extract_length, &pkt->rbsp, nal, small_padding);
484 if (consumed < 0)
485 return consumed;
486
487 if (is_nalff && (extract_length != consumed) && extract_length)
488 av_log(logctx, AV_LOG_DEBUG,
489 "NALFF: Consumed only %d bytes instead of %d\n",
490 consumed, extract_length);
491
492 bytestream2_skip(&bc, consumed);
493
494 /* see commit 3566042a0 */
495 if (bytestream2_get_bytes_left(&bc) >= 4 &&
496 bytestream2_peek_be32(&bc) == 0x000001E0)
497 skip_trailing_zeros = 0;
498
499 nal->size_bits = get_bit_length(nal, 1 + (codec_id == AV_CODEC_ID_HEVC),
500 skip_trailing_zeros);
501
502 if (nal->size <= 0 || nal->size_bits <= 0)
503 continue;
504
505 ret = init_get_bits(&nal->gb, nal->data, nal->size_bits);
506 if (ret < 0)
507 return ret;
508
509 /* Reset type in case it contains a stale value from a previously parsed NAL */
510 nal->type = 0;
511
512 if (codec_id == AV_CODEC_ID_HEVC)
513 ret = hevc_parse_nal_header(nal, logctx);
514 else
515 ret = h264_parse_nal_header(nal, logctx);
516 if (ret < 0) {
517 av_log(logctx, AV_LOG_WARNING, "Invalid NAL unit %d, skipping.\n",
518 nal->type);
519 continue;
520 }
521
522 pkt->nb_nals++;
523 }
524
525 return 0;
526 }
527
ff_h2645_packet_uninit(H2645Packet * pkt)528 void ff_h2645_packet_uninit(H2645Packet *pkt)
529 {
530 int i;
531 for (i = 0; i < pkt->nals_allocated; i++) {
532 av_freep(&pkt->nals[i].skipped_bytes_pos);
533 }
534 av_freep(&pkt->nals);
535 pkt->nals_allocated = pkt->nal_buffer_size = 0;
536 if (pkt->rbsp.rbsp_buffer_ref) {
537 av_buffer_unref(&pkt->rbsp.rbsp_buffer_ref);
538 pkt->rbsp.rbsp_buffer = NULL;
539 } else
540 av_freep(&pkt->rbsp.rbsp_buffer);
541 pkt->rbsp.rbsp_buffer_alloc_size = pkt->rbsp.rbsp_buffer_size = 0;
542 }
543