2 * This file is part of FFmpeg.
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 #include "bytestream.h"
23 #include "h264_parse.h"
25 int ff_h264_pred_weight_table(GetBitContext *gb, const SPS *sps,
26 const int *ref_count, int slice_type_nos,
27 H264PredWeightTable *pwt, void *logctx)
30 int luma_def, chroma_def;
33 pwt->use_weight_chroma = 0;
34 pwt->luma_log2_weight_denom = get_ue_golomb(gb);
35 if (sps->chroma_format_idc)
36 pwt->chroma_log2_weight_denom = get_ue_golomb(gb);
38 if (pwt->luma_log2_weight_denom > 7U) {
39 av_log(logctx, AV_LOG_ERROR, "luma_log2_weight_denom %d is out of range\n", pwt->luma_log2_weight_denom);
40 pwt->luma_log2_weight_denom = 0;
42 if (pwt->chroma_log2_weight_denom > 7U) {
43 av_log(logctx, AV_LOG_ERROR, "chroma_log2_weight_denom %d is out of range\n", pwt->chroma_log2_weight_denom);
44 pwt->chroma_log2_weight_denom = 0;
47 luma_def = 1 << pwt->luma_log2_weight_denom;
48 chroma_def = 1 << pwt->chroma_log2_weight_denom;
50 for (list = 0; list < 2; list++) {
51 pwt->luma_weight_flag[list] = 0;
52 pwt->chroma_weight_flag[list] = 0;
53 for (i = 0; i < ref_count[list]; i++) {
54 int luma_weight_flag, chroma_weight_flag;
56 luma_weight_flag = get_bits1(gb);
57 if (luma_weight_flag) {
58 pwt->luma_weight[i][list][0] = get_se_golomb(gb);
59 pwt->luma_weight[i][list][1] = get_se_golomb(gb);
60 if (pwt->luma_weight[i][list][0] != luma_def ||
61 pwt->luma_weight[i][list][1] != 0) {
63 pwt->luma_weight_flag[list] = 1;
66 pwt->luma_weight[i][list][0] = luma_def;
67 pwt->luma_weight[i][list][1] = 0;
70 if (sps->chroma_format_idc) {
71 chroma_weight_flag = get_bits1(gb);
72 if (chroma_weight_flag) {
74 for (j = 0; j < 2; j++) {
75 pwt->chroma_weight[i][list][j][0] = get_se_golomb(gb);
76 pwt->chroma_weight[i][list][j][1] = get_se_golomb(gb);
77 if (pwt->chroma_weight[i][list][j][0] != chroma_def ||
78 pwt->chroma_weight[i][list][j][1] != 0) {
79 pwt->use_weight_chroma = 1;
80 pwt->chroma_weight_flag[list] = 1;
85 for (j = 0; j < 2; j++) {
86 pwt->chroma_weight[i][list][j][0] = chroma_def;
87 pwt->chroma_weight[i][list][j][1] = 0;
92 if (slice_type_nos != AV_PICTURE_TYPE_B)
95 pwt->use_weight = pwt->use_weight || pwt->use_weight_chroma;
100 * Check if the top & left blocks are available if needed and
101 * change the dc mode so it only uses the available blocks.
103 int ff_h264_check_intra4x4_pred_mode(int8_t *pred_mode_cache, void *logctx,
104 int top_samples_available, int left_samples_available)
106 static const int8_t top[12] = {
107 -1, 0, LEFT_DC_PRED, -1, -1, -1, -1, -1, 0
109 static const int8_t left[12] = {
110 0, -1, TOP_DC_PRED, 0, -1, -1, -1, 0, -1, DC_128_PRED
114 if (!(top_samples_available & 0x8000)) {
115 for (i = 0; i < 4; i++) {
116 int status = top[pred_mode_cache[scan8[0] + i]];
118 av_log(logctx, AV_LOG_ERROR,
119 "top block unavailable for requested intra mode %d\n",
121 return AVERROR_INVALIDDATA;
123 pred_mode_cache[scan8[0] + i] = status;
128 if ((left_samples_available & 0x8888) != 0x8888) {
129 static const int mask[4] = { 0x8000, 0x2000, 0x80, 0x20 };
130 for (i = 0; i < 4; i++)
131 if (!(left_samples_available & mask[i])) {
132 int status = left[pred_mode_cache[scan8[0] + 8 * i]];
134 av_log(logctx, AV_LOG_ERROR,
135 "left block unavailable for requested intra4x4 mode %d\n",
137 return AVERROR_INVALIDDATA;
139 pred_mode_cache[scan8[0] + 8 * i] = status;
148 * Check if the top & left blocks are available if needed and
149 * change the dc mode so it only uses the available blocks.
151 int ff_h264_check_intra_pred_mode(void *logctx, int top_samples_available,
152 int left_samples_available,
153 int mode, int is_chroma)
155 static const int8_t top[4] = { LEFT_DC_PRED8x8, 1, -1, -1 };
156 static const int8_t left[5] = { TOP_DC_PRED8x8, -1, 2, -1, DC_128_PRED8x8 };
159 av_log(logctx, AV_LOG_ERROR,
160 "out of range intra chroma pred mode\n");
161 return AVERROR_INVALIDDATA;
164 if (!(top_samples_available & 0x8000)) {
167 av_log(logctx, AV_LOG_ERROR,
168 "top block unavailable for requested intra mode\n");
169 return AVERROR_INVALIDDATA;
173 if ((left_samples_available & 0x8080) != 0x8080) {
176 av_log(logctx, AV_LOG_ERROR,
177 "left block unavailable for requested intra mode\n");
178 return AVERROR_INVALIDDATA;
180 if (is_chroma && (left_samples_available & 0x8080)) {
181 // mad cow disease mode, aka MBAFF + constrained_intra_pred
182 mode = ALZHEIMER_DC_L0T_PRED8x8 +
183 (!(left_samples_available & 0x8000)) +
184 2 * (mode == DC_128_PRED8x8);
191 int ff_h264_parse_ref_count(int *plist_count, int ref_count[2],
192 GetBitContext *gb, const PPS *pps,
193 int slice_type_nos, int picture_structure, void *logctx)
196 int num_ref_idx_active_override_flag;
198 // set defaults, might be overridden a few lines later
199 ref_count[0] = pps->ref_count[0];
200 ref_count[1] = pps->ref_count[1];
202 if (slice_type_nos != AV_PICTURE_TYPE_I) {
204 max[0] = max[1] = picture_structure == PICT_FRAME ? 15 : 31;
206 num_ref_idx_active_override_flag = get_bits1(gb);
208 if (num_ref_idx_active_override_flag) {
209 ref_count[0] = get_ue_golomb(gb) + 1;
210 if (slice_type_nos == AV_PICTURE_TYPE_B) {
211 ref_count[1] = get_ue_golomb(gb) + 1;
213 // full range is spec-ok in this case, even for frames
217 if (ref_count[0] - 1 > max[0] || ref_count[1] - 1 > max[1]) {
218 av_log(logctx, AV_LOG_ERROR, "reference overflow %u > %u or %u > %u\n",
219 ref_count[0] - 1, max[0], ref_count[1] - 1, max[1]);
220 ref_count[0] = ref_count[1] = 0;
225 if (slice_type_nos == AV_PICTURE_TYPE_B)
231 ref_count[0] = ref_count[1] = 0;
234 *plist_count = list_count;
241 return AVERROR_INVALIDDATA;
244 int ff_h264_init_poc(int pic_field_poc[2], int *pic_poc,
245 const SPS *sps, H264POCContext *pc,
246 int picture_structure, int nal_ref_idc)
248 const int max_frame_num = 1 << sps->log2_max_frame_num;
251 pc->frame_num_offset = pc->prev_frame_num_offset;
252 if (pc->frame_num < pc->prev_frame_num)
253 pc->frame_num_offset += max_frame_num;
255 if (sps->poc_type == 0) {
256 const int max_poc_lsb = 1 << sps->log2_max_poc_lsb;
258 if (pc->poc_lsb < pc->prev_poc_lsb &&
259 pc->prev_poc_lsb - pc->poc_lsb >= max_poc_lsb / 2)
260 pc->poc_msb = pc->prev_poc_msb + max_poc_lsb;
261 else if (pc->poc_lsb > pc->prev_poc_lsb &&
262 pc->prev_poc_lsb - pc->poc_lsb < -max_poc_lsb / 2)
263 pc->poc_msb = pc->prev_poc_msb - max_poc_lsb;
265 pc->poc_msb = pc->prev_poc_msb;
267 field_poc[1] = pc->poc_msb + pc->poc_lsb;
268 if (picture_structure == PICT_FRAME)
269 field_poc[1] += pc->delta_poc_bottom;
270 } else if (sps->poc_type == 1) {
271 int abs_frame_num, expected_delta_per_poc_cycle, expectedpoc;
274 if (sps->poc_cycle_length != 0)
275 abs_frame_num = pc->frame_num_offset + pc->frame_num;
279 if (nal_ref_idc == 0 && abs_frame_num > 0)
282 expected_delta_per_poc_cycle = 0;
283 for (i = 0; i < sps->poc_cycle_length; i++)
284 // FIXME integrate during sps parse
285 expected_delta_per_poc_cycle += sps->offset_for_ref_frame[i];
287 if (abs_frame_num > 0) {
288 int poc_cycle_cnt = (abs_frame_num - 1) / sps->poc_cycle_length;
289 int frame_num_in_poc_cycle = (abs_frame_num - 1) % sps->poc_cycle_length;
291 expectedpoc = poc_cycle_cnt * expected_delta_per_poc_cycle;
292 for (i = 0; i <= frame_num_in_poc_cycle; i++)
293 expectedpoc = expectedpoc + sps->offset_for_ref_frame[i];
297 if (nal_ref_idc == 0)
298 expectedpoc = expectedpoc + sps->offset_for_non_ref_pic;
300 field_poc[0] = expectedpoc + pc->delta_poc[0];
301 field_poc[1] = field_poc[0] + sps->offset_for_top_to_bottom_field;
303 if (picture_structure == PICT_FRAME)
304 field_poc[1] += pc->delta_poc[1];
306 int poc = 2 * (pc->frame_num_offset + pc->frame_num);
315 if (picture_structure != PICT_BOTTOM_FIELD)
316 pic_field_poc[0] = field_poc[0];
317 if (picture_structure != PICT_TOP_FIELD)
318 pic_field_poc[1] = field_poc[1];
319 *pic_poc = FFMIN(pic_field_poc[0], pic_field_poc[1]);
324 static int decode_extradata_ps(const uint8_t *data, int size, H264ParamSets *ps,
325 int is_avc, void *logctx)
327 H2645Packet pkt = { 0 };
330 ret = ff_h2645_packet_split(&pkt, data, size, logctx, is_avc, 2, AV_CODEC_ID_H264);
336 for (i = 0; i < pkt.nb_nals; i++) {
337 H2645NAL *nal = &pkt.nals[i];
340 ret = ff_h264_decode_seq_parameter_set(&nal->gb, logctx, ps, 0);
345 ret = ff_h264_decode_picture_parameter_set(&nal->gb, logctx, ps,
351 av_log(logctx, AV_LOG_VERBOSE, "Ignoring NAL type %d in extradata\n",
358 ff_h2645_packet_uninit(&pkt);
362 /* There are (invalid) samples in the wild with mp4-style extradata, where the
363 * parameter sets are stored unescaped (i.e. as RBSP).
364 * This function catches the parameter set decoding failure and tries again
365 * after escaping it */
366 static int decode_extradata_ps_mp4(const uint8_t *buf, int buf_size, H264ParamSets *ps,
367 int err_recognition, void *logctx)
371 ret = decode_extradata_ps(buf, buf_size, ps, 1, logctx);
372 if (ret < 0 && !(err_recognition & AV_EF_EXPLODE)) {
375 uint8_t *escaped_buf;
376 int escaped_buf_size;
378 av_log(logctx, AV_LOG_WARNING,
379 "SPS decoding failure, trying again after escaping the NAL\n");
381 if (buf_size / 2 >= (INT16_MAX - AV_INPUT_BUFFER_PADDING_SIZE) / 3)
382 return AVERROR(ERANGE);
383 escaped_buf_size = buf_size * 3 / 2 + AV_INPUT_BUFFER_PADDING_SIZE;
384 escaped_buf = av_mallocz(escaped_buf_size);
386 return AVERROR(ENOMEM);
388 bytestream2_init(&gbc, buf, buf_size);
389 bytestream2_init_writer(&pbc, escaped_buf, escaped_buf_size);
391 while (bytestream2_get_bytes_left(&gbc)) {
392 if (bytestream2_get_bytes_left(&gbc) >= 3 &&
393 bytestream2_peek_be24(&gbc) <= 3) {
394 bytestream2_put_be24(&pbc, 3);
395 bytestream2_skip(&gbc, 2);
397 bytestream2_put_byte(&pbc, bytestream2_get_byte(&gbc));
400 escaped_buf_size = bytestream2_tell_p(&pbc);
401 AV_WB16(escaped_buf, escaped_buf_size - 2);
403 ret = decode_extradata_ps(escaped_buf, escaped_buf_size, ps, 1, logctx);
404 av_freep(&escaped_buf);
412 int ff_h264_decode_extradata(const uint8_t *data, int size, H264ParamSets *ps,
413 int *is_avc, int *nal_length_size,
414 int err_recognition, void *logctx)
418 if (!data || size <= 0)
423 const uint8_t *p = data;
428 av_log(logctx, AV_LOG_ERROR, "avcC %d too short\n", size);
429 return AVERROR_INVALIDDATA;
432 // Decode sps from avcC
433 cnt = *(p + 5) & 0x1f; // Number of sps
435 for (i = 0; i < cnt; i++) {
436 nalsize = AV_RB16(p) + 2;
437 if (nalsize > size - (p - data))
438 return AVERROR_INVALIDDATA;
439 ret = decode_extradata_ps_mp4(p, nalsize, ps, err_recognition, logctx);
441 av_log(logctx, AV_LOG_ERROR,
442 "Decoding sps %d from avcC failed\n", i);
447 // Decode pps from avcC
448 cnt = *(p++); // Number of pps
449 for (i = 0; i < cnt; i++) {
450 nalsize = AV_RB16(p) + 2;
451 if (nalsize > size - (p - data))
452 return AVERROR_INVALIDDATA;
453 ret = decode_extradata_ps_mp4(p, nalsize, ps, err_recognition, logctx);
455 av_log(logctx, AV_LOG_ERROR,
456 "Decoding pps %d from avcC failed\n", i);
461 // Store right nal length size that will be used to parse all other nals
462 *nal_length_size = (data[4] & 0x03) + 1;
465 ret = decode_extradata_ps(data, size, ps, 0, logctx);
473 * Compute profile from profile_idc and constraint_set?_flags.
477 * @return profile as defined by FF_PROFILE_H264_*
479 int ff_h264_get_profile(const SPS *sps)
481 int profile = sps->profile_idc;
483 switch (sps->profile_idc) {
484 case FF_PROFILE_H264_BASELINE:
485 // constraint_set1_flag set to 1
486 profile |= (sps->constraint_set_flags & 1 << 1) ? FF_PROFILE_H264_CONSTRAINED : 0;
488 case FF_PROFILE_H264_HIGH_10:
489 case FF_PROFILE_H264_HIGH_422:
490 case FF_PROFILE_H264_HIGH_444_PREDICTIVE:
491 // constraint_set3_flag set to 1
492 profile |= (sps->constraint_set_flags & 1 << 3) ? FF_PROFILE_H264_INTRA : 0;