2 * HEVC Annex B format parser
4 * Copyright (C) 2012 - 2013 Guillaume Martres
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include "libavutil/common.h"
29 #define START_CODE 0x000001 ///< start_code_prefix_one_3bytes
31 #define IS_IRAP_NAL(nal) (nal->type >= 16 && nal->type <= 23)
33 #define ADVANCED_PARSER CONFIG_HEVC_DECODER
35 typedef struct HEVCParserContext {
49 static int hevc_parse_slice_header(AVCodecParserContext *s, HEVCNAL *nal,
50 AVCodecContext *avctx)
52 HEVCParserContext *ctx = s->priv_data;
53 GetBitContext *gb = &nal->gb;
59 get_bits1(gb); // first slice in pic
61 get_bits1(gb); // no output of prior pics
63 pps_id = get_ue_golomb_long(gb);
64 if (pps_id >= MAX_PPS_COUNT || !ctx->ps.pps_list[pps_id]) {
65 av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", pps_id);
66 return AVERROR_INVALIDDATA;
68 pps = (HEVCPPS*)ctx->ps.pps_list[pps_id]->data;
69 sps = (HEVCSPS*)ctx->ps.sps_list[pps->sps_id]->data;
71 /* export the stream parameters */
72 s->coded_width = sps->width;
73 s->coded_height = sps->height;
74 s->width = sps->output_width;
75 s->height = sps->output_height;
76 s->format = sps->pix_fmt;
77 avctx->profile = sps->ptl.general_ptl.profile_idc;
78 avctx->level = sps->ptl.general_ptl.level_idc;
80 /* ignore the rest for now*/
85 static int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf,
86 int buf_size, AVCodecContext *avctx)
88 HEVCParserContext *ctx = s->priv_data;
91 ret = ff_hevc_split_packet(NULL, &ctx->pkt, buf, buf_size, avctx, 0, 0);
95 for (i = 0; i < ctx->pkt.nb_nals; i++) {
96 HEVCNAL *nal = &ctx->pkt.nals[i];
98 /* ignore everything except parameter sets and VCL NALUs */
100 case NAL_VPS: ff_hevc_decode_nal_vps(&nal->gb, avctx, &ctx->ps); break;
101 case NAL_SPS: ff_hevc_decode_nal_sps(&nal->gb, avctx, &ctx->ps, 1); break;
102 case NAL_PPS: ff_hevc_decode_nal_pps(&nal->gb, avctx, &ctx->ps); break;
119 if (buf == avctx->extradata) {
120 av_log(avctx, AV_LOG_ERROR, "Invalid NAL unit: %d\n", nal->type);
121 return AVERROR_INVALIDDATA;
123 hevc_parse_slice_header(s, nal, avctx);
133 * Find the end of the current frame in the bitstream.
134 * @return the position of the first byte of the next frame, or END_NOT_FOUND
136 static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf,
140 ParseContext *pc = s->priv_data;
142 for (i = 0; i < buf_size; i++) {
145 pc->state64 = (pc->state64 << 8) | buf[i];
147 if (((pc->state64 >> 3 * 8) & 0xFFFFFF) != START_CODE)
150 nut = (pc->state64 >> 2 * 8 + 1) & 0x3F;
151 // Beginning of access unit
152 if ((nut >= NAL_VPS && nut <= NAL_AUD) || nut == NAL_SEI_PREFIX ||
153 (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) {
154 if (pc->frame_start_found) {
155 pc->frame_start_found = 0;
158 } else if (nut <= NAL_RASL_R ||
159 (nut >= NAL_BLA_W_LP && nut <= NAL_CRA_NUT)) {
160 int first_slice_segment_in_pic_flag = buf[i] >> 7;
161 if (first_slice_segment_in_pic_flag) {
162 if (!pc->frame_start_found) {
163 pc->frame_start_found = 1;
164 } else { // First slice of next frame found
165 pc->frame_start_found = 0;
172 return END_NOT_FOUND;
177 * Parse NAL units of found picture and decode some basic information.
179 * @param s parser context.
180 * @param avctx codec context.
181 * @param buf buffer with field/frame data.
182 * @param buf_size size of the buffer.
184 static inline int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf,
185 int buf_size, AVCodecContext *avctx)
187 HEVCParserContext *ctx = s->priv_data;
188 HEVCContext *h = &ctx->h;
190 SliceHeader *sh = &h->sh;
191 HEVCParamSets *ps = &h->ps;
192 HEVCPacket *pkt = &ctx->pkt;
193 const uint8_t *buf_end = buf + buf_size;
196 int is_global = buf == avctx->extradata;
199 h->HEVClc = av_mallocz(sizeof(HEVCLocalContext));
201 return AVERROR(ENOMEM);
205 /* set some sane default values */
206 s->pict_type = AV_PICTURE_TYPE_I;
208 s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
215 if (pkt->nals_allocated < 1) {
216 HEVCNAL *tmp = av_realloc_array(pkt->nals, 1, sizeof(*tmp));
218 return AVERROR(ENOMEM);
220 memset(pkt->nals, 0, sizeof(*tmp));
221 pkt->nals_allocated = 1;
227 int src_length, consumed;
228 buf = avpriv_find_start_code(buf, buf_end, &state);
229 if (--buf + 2 >= buf_end)
231 src_length = buf_end - buf;
233 h->nal_unit_type = (*buf >> 1) & 0x3f;
234 h->temporal_id = (*(buf + 1) & 0x07) - 1;
235 if (h->nal_unit_type <= NAL_CRA_NUT) {
236 // Do not walk the whole buffer just to decode slice segment header
241 consumed = ff_hevc_extract_rbsp(NULL, buf, src_length, nal);
245 init_get_bits8(gb, nal->data + 2, nal->size);
246 switch (h->nal_unit_type) {
248 ff_hevc_decode_nal_vps(gb, avctx, ps);
251 ff_hevc_decode_nal_sps(gb, avctx, ps, 1);
254 ff_hevc_decode_nal_pps(gb, avctx, ps);
258 ff_hevc_decode_nal_sei(h);
278 av_log(avctx, AV_LOG_ERROR, "Invalid NAL unit: %d\n", h->nal_unit_type);
279 return AVERROR_INVALIDDATA;
282 sh->first_slice_in_pic_flag = get_bits1(gb);
283 s->picture_structure = h->picture_struct;
284 s->field_order = h->picture_struct;
288 sh->no_output_of_prior_pics_flag = get_bits1(gb);
291 sh->pps_id = get_ue_golomb(gb);
292 if (sh->pps_id >= MAX_PPS_COUNT || !ps->pps_list[sh->pps_id]) {
293 av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", sh->pps_id);
294 return AVERROR_INVALIDDATA;
296 ps->pps = (HEVCPPS*)ps->pps_list[sh->pps_id]->data;
298 if (ps->pps->sps_id >= MAX_SPS_COUNT || !ps->sps_list[ps->pps->sps_id]) {
299 av_log(avctx, AV_LOG_ERROR, "SPS id out of range: %d\n", ps->pps->sps_id);
300 return AVERROR_INVALIDDATA;
302 if (ps->sps != (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data) {
303 ps->sps = (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data;
304 ps->vps = (HEVCVPS*)ps->vps_list[ps->sps->vps_id]->data;
307 if (!sh->first_slice_in_pic_flag) {
308 int slice_address_length;
310 if (ps->pps->dependent_slice_segments_enabled_flag)
311 sh->dependent_slice_segment_flag = get_bits1(gb);
313 sh->dependent_slice_segment_flag = 0;
315 slice_address_length = av_ceil_log2_c(ps->sps->ctb_width *
316 ps->sps->ctb_height);
317 sh->slice_segment_addr = slice_address_length ? get_bits(gb, slice_address_length) : 0;
318 if (sh->slice_segment_addr >= ps->sps->ctb_width * ps->sps->ctb_height) {
319 av_log(avctx, AV_LOG_ERROR, "Invalid slice segment address: %u.\n",
320 sh->slice_segment_addr);
321 return AVERROR_INVALIDDATA;
324 sh->dependent_slice_segment_flag = 0;
326 if (sh->dependent_slice_segment_flag)
329 for (i = 0; i < ps->pps->num_extra_slice_header_bits; i++)
330 skip_bits(gb, 1); // slice_reserved_undetermined_flag[]
332 sh->slice_type = get_ue_golomb(gb);
333 if (!(sh->slice_type == I_SLICE || sh->slice_type == P_SLICE ||
334 sh->slice_type == B_SLICE)) {
335 av_log(avctx, AV_LOG_ERROR, "Unknown slice type: %d.\n",
337 return AVERROR_INVALIDDATA;
339 s->pict_type = sh->slice_type == B_SLICE ? AV_PICTURE_TYPE_B :
340 sh->slice_type == P_SLICE ? AV_PICTURE_TYPE_P :
343 if (ps->pps->output_flag_present_flag)
344 sh->pic_output_flag = get_bits1(gb);
346 if (ps->sps->separate_colour_plane_flag)
347 sh->colour_plane_id = get_bits(gb, 2);
350 sh->pic_order_cnt_lsb = get_bits(gb, ps->sps->log2_max_poc_lsb);
351 s->output_picture_number = h->poc = ff_hevc_compute_poc(h, sh->pic_order_cnt_lsb);
353 s->output_picture_number = h->poc = 0;
355 if (h->temporal_id == 0 &&
356 h->nal_unit_type != NAL_TRAIL_N &&
357 h->nal_unit_type != NAL_TSA_N &&
358 h->nal_unit_type != NAL_STSA_N &&
359 h->nal_unit_type != NAL_RADL_N &&
360 h->nal_unit_type != NAL_RASL_N &&
361 h->nal_unit_type != NAL_RADL_R &&
362 h->nal_unit_type != NAL_RASL_R)
365 return 0; /* no need to evaluate the rest */
369 /* didn't find a picture! */
371 av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n");
376 static int hevc_parse(AVCodecParserContext *s,
377 AVCodecContext *avctx,
378 const uint8_t **poutbuf, int *poutbuf_size,
379 const uint8_t *buf, int buf_size)
382 HEVCParserContext *ctx = s->priv_data;
383 ParseContext *pc = &ctx->pc;
385 if (avctx->extradata && !ctx->parsed_extradata) {
386 parse_nal_units(s, avctx->extradata, avctx->extradata_size, avctx);
387 ctx->parsed_extradata = 1;
390 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
393 next = hevc_find_frame_end(s, buf, buf_size);
394 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
401 parse_nal_units(s, buf, buf_size, avctx);
404 *poutbuf_size = buf_size;
408 // Split after the parameter sets at the beginning of the stream if they exist.
409 static int hevc_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
411 const uint8_t *ptr = buf, *end = buf + buf_size;
416 ptr = avpriv_find_start_code(ptr, end, &state);
417 if ((state >> 8) != START_CODE)
419 nut = (state >> 1) & 0x3F;
420 if (nut >= NAL_VPS && nut <= NAL_PPS)
423 return ptr - 4 - buf;
424 else // no parameter set at the beginning of the stream
430 static void hevc_parser_close(AVCodecParserContext *s)
432 HEVCParserContext *ctx = s->priv_data;
436 HEVCContext *h = &ctx->h;
438 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.vps_list); i++)
439 av_buffer_unref(&h->ps.vps_list[i]);
440 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.sps_list); i++)
441 av_buffer_unref(&h->ps.sps_list[i]);
442 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.pps_list); i++)
443 av_buffer_unref(&h->ps.pps_list[i]);
447 av_freep(&h->HEVClc);
450 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.vps_list); i++)
451 av_buffer_unref(&ctx->ps.vps_list[i]);
452 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.sps_list); i++)
453 av_buffer_unref(&ctx->ps.sps_list[i]);
454 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.pps_list); i++)
455 av_buffer_unref(&ctx->ps.pps_list[i]);
459 for (i = 0; i < ctx->pkt.nals_allocated; i++) {
460 av_freep(&ctx->pkt.nals[i].rbsp_buffer);
461 av_freep(&ctx->pkt.nals[i].skipped_bytes_pos);
463 av_freep(&ctx->pkt.nals);
464 ctx->pkt.nals_allocated = 0;
466 av_freep(&ctx->pc.buffer);
469 AVCodecParser ff_hevc_parser = {
470 .codec_ids = { AV_CODEC_ID_HEVC },
471 .priv_data_size = sizeof(HEVCParserContext),
472 .parser_parse = hevc_parse,
473 .parser_close = hevc_parser_close,