2 * H.264/HEVC common parsing code
4 * This file is part of FFmpeg.
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.
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.
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
25 #include "libavutil/intmath.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/mem.h"
29 #include "bytestream.h"
32 #include "h2645_parse.h"
34 int ff_h2645_extract_rbsp(const uint8_t *src, int length,
35 H2645RBSP *rbsp, H2645NAL *nal, int small_padding)
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 */ \
49 #if HAVE_FAST_UNALIGNED
50 #define FIND_FIRST_ZERO \
51 if (i > 0 && !src[i]) \
56 for (i = 0; i + 1 < length; i += 9) {
57 if (!((~AV_RN64(src + i) &
58 (AV_RN64(src + i) - 0x0100010001000101ULL)) &
59 0x8000800080008080ULL))
66 for (i = 0; i + 1 < length; i += 5) {
67 if (!((~AV_RN32(src + i) &
68 (AV_RN32(src + i) - 0x01000101U)) &
75 #endif /* HAVE_FAST_64BIT */
77 for (i = 0; i + 1 < length; i += 2) {
80 if (i > 0 && src[i - 1] == 0)
84 #endif /* HAVE_FAST_UNALIGNED */
86 if (i >= length - 1 && small_padding) { // no escaped 0
90 nal->raw_size = length;
92 } else if (i > length)
95 nal->rbsp_buffer = &rbsp->rbsp_buffer[rbsp->rbsp_buffer_size];
96 dst = nal->rbsp_buffer;
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
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);
124 if (nal->skipped_bytes_pos)
125 nal->skipped_bytes_pos[nal->skipped_bytes-1] = di - 1;
128 } else // next start code
132 dst[di++] = src[si++];
135 dst[di++] = src[si++];
138 memset(dst + di, 0, AV_INPUT_BUFFER_PADDING_SIZE);
144 rbsp->rbsp_buffer_size += si;
149 static const char *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 "IRAP_IRAP_VCL22", // HEVC_NAL_IRAP_VCL22
173 "IRAP_IRAP_VCL23", // HEVC_NAL_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
216 static const char *hevc_nal_unit_name(int nal_type)
218 av_assert0(nal_type >= 0 && nal_type < 64);
219 return hevc_nal_type_name[nal_type];
222 static const char *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
257 static const char *h264_nal_unit_name(int nal_type)
259 av_assert0(nal_type >= 0 && nal_type < 32);
260 return h264_nal_type_name[nal_type];
263 static int get_bit_length(H2645NAL *nal, int skip_trailing_zeros)
265 int size = nal->size;
268 while (skip_trailing_zeros && size > 0 && nal->data[size - 1] == 0)
274 v = nal->data[size - 1];
276 if (size > INT_MAX / 8)
277 return AVERROR(ERANGE);
280 /* remove the stop bit and following trailing zeros,
281 * or nothing for damaged bitstreams */
283 size -= ff_ctz(v) + 1;
289 * @return AVERROR_INVALIDDATA if the packet is not a valid NAL unit,
290 * 0 if the unit should be skipped, 1 otherwise
292 static int hevc_parse_nal_header(H2645NAL *nal, void *logctx)
294 GetBitContext *gb = &nal->gb;
297 if (get_bits1(gb) != 0)
298 return AVERROR_INVALIDDATA;
300 nal->type = get_bits(gb, 6);
302 nuh_layer_id = get_bits(gb, 6);
303 nal->temporal_id = get_bits(gb, 3) - 1;
304 if (nal->temporal_id < 0)
305 return AVERROR_INVALIDDATA;
307 av_log(logctx, AV_LOG_DEBUG,
308 "nal_unit_type: %d(%s), nuh_layer_id: %d, temporal_id: %d\n",
309 nal->type, hevc_nal_unit_name(nal->type), nuh_layer_id, nal->temporal_id);
311 return nuh_layer_id == 0;
314 static int h264_parse_nal_header(H2645NAL *nal, void *logctx)
316 GetBitContext *gb = &nal->gb;
318 if (get_bits1(gb) != 0)
319 return AVERROR_INVALIDDATA;
321 nal->ref_idc = get_bits(gb, 2);
322 nal->type = get_bits(gb, 5);
324 av_log(logctx, AV_LOG_DEBUG,
325 "nal_unit_type: %d(%s), nal_ref_idc: %d\n",
326 nal->type, h264_nal_unit_name(nal->type), nal->ref_idc);
331 static int find_next_start_code(const uint8_t *buf, const uint8_t *next_avc)
335 if (buf + 3 >= next_avc)
336 return next_avc - buf;
338 while (buf + i + 3 < next_avc) {
339 if (buf[i] == 0 && buf[i + 1] == 0 && buf[i + 2] == 1)
346 int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length,
347 void *logctx, int is_nalff, int nal_length_size,
348 enum AVCodecID codec_id, int small_padding)
351 int consumed, ret = 0;
352 int next_avc = is_nalff ? 0 : length;
353 int64_t padding = small_padding ? 0 : MAX_MBPAIR_SIZE;
355 bytestream2_init(&bc, buf, length);
356 av_fast_padded_malloc(&pkt->rbsp.rbsp_buffer, &pkt->rbsp.rbsp_buffer_alloc_size, length + padding);
357 if (!pkt->rbsp.rbsp_buffer)
358 return AVERROR(ENOMEM);
360 pkt->rbsp.rbsp_buffer_size = 0;
362 while (bytestream2_get_bytes_left(&bc) >= 4) {
364 int extract_length = 0;
365 int skip_trailing_zeros = 1;
367 if (bytestream2_tell(&bc) == next_avc) {
369 extract_length = get_nalsize(nal_length_size,
370 bc.buffer, bytestream2_get_bytes_left(&bc), &i, logctx);
371 if (extract_length < 0)
372 return extract_length;
374 bytestream2_skip(&bc, nal_length_size);
376 next_avc = bytestream2_tell(&bc) + extract_length;
380 if (bytestream2_tell(&bc) > next_avc)
381 av_log(logctx, AV_LOG_WARNING, "Exceeded next NALFF position, re-syncing.\n");
383 /* search start code */
384 buf_index = find_next_start_code(bc.buffer, buf + next_avc);
386 bytestream2_skip(&bc, buf_index);
388 if (!bytestream2_get_bytes_left(&bc)) {
389 if (pkt->nb_nals > 0) {
390 // No more start codes: we discarded some irrelevant
391 // bytes at the end of the packet.
394 av_log(logctx, AV_LOG_ERROR, "No start code is found.\n");
395 return AVERROR_INVALIDDATA;
399 extract_length = FFMIN(bytestream2_get_bytes_left(&bc), next_avc - bytestream2_tell(&bc));
401 if (bytestream2_tell(&bc) >= next_avc) {
402 /* skip to the start of the next NAL */
403 bytestream2_skip(&bc, next_avc - bytestream2_tell(&bc));
408 if (pkt->nals_allocated < pkt->nb_nals + 1) {
409 int new_size = pkt->nals_allocated + 1;
410 void *tmp = av_realloc_array(pkt->nals, new_size, sizeof(*pkt->nals));
413 return AVERROR(ENOMEM);
416 memset(pkt->nals + pkt->nals_allocated, 0,
417 (new_size - pkt->nals_allocated) * sizeof(*pkt->nals));
419 nal = &pkt->nals[pkt->nb_nals];
420 nal->skipped_bytes_pos_size = 1024; // initial buffer size
421 nal->skipped_bytes_pos = av_malloc_array(nal->skipped_bytes_pos_size, sizeof(*nal->skipped_bytes_pos));
422 if (!nal->skipped_bytes_pos)
423 return AVERROR(ENOMEM);
425 pkt->nals_allocated = new_size;
427 nal = &pkt->nals[pkt->nb_nals];
429 consumed = ff_h2645_extract_rbsp(bc.buffer, extract_length, &pkt->rbsp, nal, small_padding);
433 if (is_nalff && (extract_length != consumed) && extract_length)
434 av_log(logctx, AV_LOG_DEBUG,
435 "NALFF: Consumed only %d bytes instead of %d\n",
436 consumed, extract_length);
440 bytestream2_skip(&bc, consumed);
442 /* see commit 3566042a0 */
443 if (bytestream2_get_bytes_left(&bc) >= 4 &&
444 bytestream2_peek_be32(&bc) == 0x000001E0)
445 skip_trailing_zeros = 0;
447 nal->size_bits = get_bit_length(nal, skip_trailing_zeros);
449 ret = init_get_bits(&nal->gb, nal->data, nal->size_bits);
453 if (codec_id == AV_CODEC_ID_HEVC)
454 ret = hevc_parse_nal_header(nal, logctx);
456 ret = h264_parse_nal_header(nal, logctx);
457 if (ret <= 0 || nal->size <= 0 || nal->size_bits <= 0) {
459 av_log(logctx, AV_LOG_ERROR, "Invalid NAL unit %d, skipping.\n",
469 void ff_h2645_packet_uninit(H2645Packet *pkt)
472 for (i = 0; i < pkt->nals_allocated; i++) {
473 av_freep(&pkt->nals[i].skipped_bytes_pos);
475 av_freep(&pkt->nals);
476 pkt->nals_allocated = 0;
477 av_freep(&pkt->rbsp.rbsp_buffer);
478 pkt->rbsp.rbsp_buffer_alloc_size = pkt->rbsp.rbsp_buffer_size = 0;