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;
118 case NAL_RASL_R: hevc_parse_slice_header(s, nal, avctx); break;
127 * Find the end of the current frame in the bitstream.
128 * @return the position of the first byte of the next frame, or END_NOT_FOUND
130 static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf,
134 ParseContext *pc = s->priv_data;
136 for (i = 0; i < buf_size; i++) {
139 pc->state64 = (pc->state64 << 8) | buf[i];
141 if (((pc->state64 >> 3 * 8) & 0xFFFFFF) != START_CODE)
144 nut = (pc->state64 >> 2 * 8 + 1) & 0x3F;
145 // Beginning of access unit
146 if ((nut >= NAL_VPS && nut <= NAL_AUD) || nut == NAL_SEI_PREFIX ||
147 (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) {
148 if (pc->frame_start_found) {
149 pc->frame_start_found = 0;
152 } else if (nut <= NAL_RASL_R ||
153 (nut >= NAL_BLA_W_LP && nut <= NAL_CRA_NUT)) {
154 int first_slice_segment_in_pic_flag = buf[i] >> 7;
155 if (first_slice_segment_in_pic_flag) {
156 if (!pc->frame_start_found) {
157 pc->frame_start_found = 1;
158 } else { // First slice of next frame found
159 pc->frame_start_found = 0;
166 return END_NOT_FOUND;
171 * Parse NAL units of found picture and decode some basic information.
173 * @param s parser context.
174 * @param avctx codec context.
175 * @param buf buffer with field/frame data.
176 * @param buf_size size of the buffer.
178 static inline int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf,
179 int buf_size, AVCodecContext *avctx)
181 HEVCParserContext *ctx = s->priv_data;
182 HEVCContext *h = &ctx->h;
184 SliceHeader *sh = &h->sh;
185 HEVCParamSets *ps = &h->ps;
186 HEVCPacket *pkt = &ctx->pkt;
187 const uint8_t *buf_end = buf + buf_size;
192 h->HEVClc = av_mallocz(sizeof(HEVCLocalContext));
194 return AVERROR(ENOMEM);
198 /* set some sane default values */
199 s->pict_type = AV_PICTURE_TYPE_I;
201 s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
208 if (pkt->nals_allocated < 1) {
209 HEVCNAL *tmp = av_realloc_array(pkt->nals, 1, sizeof(*tmp));
211 return AVERROR(ENOMEM);
213 memset(pkt->nals, 0, sizeof(*tmp));
214 pkt->nals_allocated = 1;
220 int src_length, consumed;
221 buf = avpriv_find_start_code(buf, buf_end, &state);
222 if (--buf + 2 >= buf_end)
224 src_length = buf_end - buf;
226 h->nal_unit_type = (*buf >> 1) & 0x3f;
227 h->temporal_id = (*(buf + 1) & 0x07) - 1;
228 if (h->nal_unit_type <= NAL_CRA_NUT) {
229 // Do not walk the whole buffer just to decode slice segment header
234 consumed = ff_hevc_extract_rbsp(NULL, buf, src_length, nal);
238 init_get_bits8(gb, nal->data + 2, nal->size);
239 switch (h->nal_unit_type) {
241 ff_hevc_decode_nal_vps(gb, avctx, ps);
244 ff_hevc_decode_nal_sps(gb, avctx, ps, 1);
247 ff_hevc_decode_nal_pps(gb, avctx, ps);
251 ff_hevc_decode_nal_sei(h);
269 sh->first_slice_in_pic_flag = get_bits1(gb);
270 s->picture_structure = h->picture_struct;
271 s->field_order = h->picture_struct;
275 sh->no_output_of_prior_pics_flag = get_bits1(gb);
278 sh->pps_id = get_ue_golomb(gb);
279 if (sh->pps_id >= MAX_PPS_COUNT || !ps->pps_list[sh->pps_id]) {
280 av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", sh->pps_id);
281 return AVERROR_INVALIDDATA;
283 ps->pps = (HEVCPPS*)ps->pps_list[sh->pps_id]->data;
285 if (ps->pps->sps_id >= MAX_SPS_COUNT || !ps->sps_list[ps->pps->sps_id]) {
286 av_log(avctx, AV_LOG_ERROR, "SPS id out of range: %d\n", ps->pps->sps_id);
287 return AVERROR_INVALIDDATA;
289 if (ps->sps != (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data) {
290 ps->sps = (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data;
291 ps->vps = (HEVCVPS*)ps->vps_list[ps->sps->vps_id]->data;
294 if (!sh->first_slice_in_pic_flag) {
295 int slice_address_length;
297 if (ps->pps->dependent_slice_segments_enabled_flag)
298 sh->dependent_slice_segment_flag = get_bits1(gb);
300 sh->dependent_slice_segment_flag = 0;
302 slice_address_length = av_ceil_log2_c(ps->sps->ctb_width *
303 ps->sps->ctb_height);
304 sh->slice_segment_addr = slice_address_length ? get_bits(gb, slice_address_length) : 0;
305 if (sh->slice_segment_addr >= ps->sps->ctb_width * ps->sps->ctb_height) {
306 av_log(avctx, AV_LOG_ERROR, "Invalid slice segment address: %u.\n",
307 sh->slice_segment_addr);
308 return AVERROR_INVALIDDATA;
311 sh->dependent_slice_segment_flag = 0;
313 if (sh->dependent_slice_segment_flag)
316 for (i = 0; i < ps->pps->num_extra_slice_header_bits; i++)
317 skip_bits(gb, 1); // slice_reserved_undetermined_flag[]
319 sh->slice_type = get_ue_golomb(gb);
320 if (!(sh->slice_type == I_SLICE || sh->slice_type == P_SLICE ||
321 sh->slice_type == B_SLICE)) {
322 av_log(avctx, AV_LOG_ERROR, "Unknown slice type: %d.\n",
324 return AVERROR_INVALIDDATA;
326 s->pict_type = sh->slice_type == B_SLICE ? AV_PICTURE_TYPE_B :
327 sh->slice_type == P_SLICE ? AV_PICTURE_TYPE_P :
330 if (ps->pps->output_flag_present_flag)
331 sh->pic_output_flag = get_bits1(gb);
333 if (ps->sps->separate_colour_plane_flag)
334 sh->colour_plane_id = get_bits(gb, 2);
337 sh->pic_order_cnt_lsb = get_bits(gb, ps->sps->log2_max_poc_lsb);
338 s->output_picture_number = h->poc = ff_hevc_compute_poc(h, sh->pic_order_cnt_lsb);
340 s->output_picture_number = h->poc = 0;
342 if (h->temporal_id == 0 &&
343 h->nal_unit_type != NAL_TRAIL_N &&
344 h->nal_unit_type != NAL_TSA_N &&
345 h->nal_unit_type != NAL_STSA_N &&
346 h->nal_unit_type != NAL_RADL_N &&
347 h->nal_unit_type != NAL_RASL_N &&
348 h->nal_unit_type != NAL_RADL_R &&
349 h->nal_unit_type != NAL_RASL_R)
352 return 0; /* no need to evaluate the rest */
356 /* didn't find a picture! */
357 av_log(h->avctx, AV_LOG_ERROR, "missing picture in access unit\n");
362 static int hevc_parse(AVCodecParserContext *s,
363 AVCodecContext *avctx,
364 const uint8_t **poutbuf, int *poutbuf_size,
365 const uint8_t *buf, int buf_size)
368 HEVCParserContext *ctx = s->priv_data;
369 ParseContext *pc = &ctx->pc;
371 if (avctx->extradata && !ctx->parsed_extradata) {
372 parse_nal_units(s, avctx->extradata, avctx->extradata_size, avctx);
373 ctx->parsed_extradata = 1;
376 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
379 next = hevc_find_frame_end(s, buf, buf_size);
380 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
387 parse_nal_units(s, buf, buf_size, avctx);
390 *poutbuf_size = buf_size;
394 // Split after the parameter sets at the beginning of the stream if they exist.
395 static int hevc_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
397 const uint8_t *ptr = buf, *end = buf + buf_size;
402 ptr = avpriv_find_start_code(ptr, end, &state);
403 if ((state >> 8) != START_CODE)
405 nut = (state >> 1) & 0x3F;
406 if (nut >= NAL_VPS && nut <= NAL_PPS)
409 return ptr - 4 - buf;
410 else // no parameter set at the beginning of the stream
416 static void hevc_parser_close(AVCodecParserContext *s)
418 HEVCParserContext *ctx = s->priv_data;
422 HEVCContext *h = &ctx->h;
424 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.vps_list); i++)
425 av_buffer_unref(&h->ps.vps_list[i]);
426 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.sps_list); i++)
427 av_buffer_unref(&h->ps.sps_list[i]);
428 for (i = 0; i < FF_ARRAY_ELEMS(h->ps.pps_list); i++)
429 av_buffer_unref(&h->ps.pps_list[i]);
433 av_freep(&h->HEVClc);
436 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.vps_list); i++)
437 av_buffer_unref(&ctx->ps.vps_list[i]);
438 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.sps_list); i++)
439 av_buffer_unref(&ctx->ps.sps_list[i]);
440 for (i = 0; i < FF_ARRAY_ELEMS(ctx->ps.pps_list); i++)
441 av_buffer_unref(&ctx->ps.pps_list[i]);
445 for (i = 0; i < ctx->pkt.nals_allocated; i++) {
446 av_freep(&ctx->pkt.nals[i].rbsp_buffer);
447 av_freep(&ctx->pkt.nals[i].skipped_bytes_pos);
449 av_freep(&ctx->pkt.nals);
450 ctx->pkt.nals_allocated = 0;
452 av_freep(&ctx->pc.buffer);
455 AVCodecParser ff_hevc_parser = {
456 .codec_ids = { AV_CODEC_ID_HEVC },
457 .priv_data_size = sizeof(HEVCParserContext),
458 .parser_parse = hevc_parse,
459 .parser_close = hevc_parser_close,