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