1 /*
2 * HEVC Annex B format parser
3 *
4 * Copyright (C) 2012 - 2013 Guillaume Martres
5 *
6 * This file is part of FFmpeg.
7 *
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.
12 *
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.
17 *
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
21 */
22
23 #include "libavutil/common.h"
24
25 #include "golomb.h"
26 #include "hevc.h"
27 #include "hevc_parse.h"
28 #include "hevc_ps.h"
29 #include "hevc_sei.h"
30 #include "h2645_parse.h"
31 #include "parser.h"
32
33 #define START_CODE 0x000001 ///< start_code_prefix_one_3bytes
34
35 #define IS_IRAP_NAL(nal) (nal->type >= 16 && nal->type <= 23)
36 #define IS_IDR_NAL(nal) (nal->type == HEVC_NAL_IDR_W_RADL || nal->type == HEVC_NAL_IDR_N_LP)
37
38 typedef struct HEVCParserContext {
39 ParseContext pc;
40
41 H2645Packet pkt;
42 HEVCParamSets ps;
43 HEVCSEI sei;
44
45 int is_avc;
46 int nal_length_size;
47 int parsed_extradata;
48
49 int poc;
50 int pocTid0;
51 } HEVCParserContext;
52
hevc_parse_slice_header(AVCodecParserContext *s, H2645NAL *nal, AVCodecContext *avctx)53 static int hevc_parse_slice_header(AVCodecParserContext *s, H2645NAL *nal,
54 AVCodecContext *avctx)
55 {
56 HEVCParserContext *ctx = s->priv_data;
57 HEVCParamSets *ps = &ctx->ps;
58 HEVCSEI *sei = &ctx->sei;
59 GetBitContext *gb = &nal->gb;
60 const HEVCWindow *ow;
61 int i, num = 0, den = 0;
62
63 unsigned int pps_id, first_slice_in_pic_flag, dependent_slice_segment_flag;
64 enum HEVCSliceType slice_type;
65
66 first_slice_in_pic_flag = get_bits1(gb);
67 s->picture_structure = sei->picture_timing.picture_struct;
68 s->field_order = sei->picture_timing.picture_struct;
69
70 if (IS_IRAP_NAL(nal)) {
71 s->key_frame = 1;
72 skip_bits1(gb); // no_output_of_prior_pics_flag
73 }
74
75 pps_id = get_ue_golomb(gb);
76 if (pps_id >= HEVC_MAX_PPS_COUNT || !ps->pps_list[pps_id]) {
77 av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", pps_id);
78 return AVERROR_INVALIDDATA;
79 }
80 ps->pps = (HEVCPPS*)ps->pps_list[pps_id]->data;
81
82 if (ps->pps->sps_id >= HEVC_MAX_SPS_COUNT || !ps->sps_list[ps->pps->sps_id]) {
83 av_log(avctx, AV_LOG_ERROR, "SPS id out of range: %d\n", ps->pps->sps_id);
84 return AVERROR_INVALIDDATA;
85 }
86 if (ps->sps != (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data) {
87 ps->sps = (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data;
88 ps->vps = (HEVCVPS*)ps->vps_list[ps->sps->vps_id]->data;
89 }
90 ow = &ps->sps->output_window;
91
92 s->coded_width = ps->sps->width;
93 s->coded_height = ps->sps->height;
94 s->width = ps->sps->width - ow->left_offset - ow->right_offset;
95 s->height = ps->sps->height - ow->top_offset - ow->bottom_offset;
96 s->format = ps->sps->pix_fmt;
97 avctx->profile = ps->sps->ptl.general_ptl.profile_idc;
98 avctx->level = ps->sps->ptl.general_ptl.level_idc;
99
100 if (ps->vps->vps_timing_info_present_flag) {
101 num = ps->vps->vps_num_units_in_tick;
102 den = ps->vps->vps_time_scale;
103 } else if (ps->sps->vui.vui_timing_info_present_flag) {
104 num = ps->sps->vui.vui_num_units_in_tick;
105 den = ps->sps->vui.vui_time_scale;
106 }
107
108 if (num != 0 && den != 0)
109 av_reduce(&avctx->framerate.den, &avctx->framerate.num,
110 num, den, 1 << 30);
111
112 if (!first_slice_in_pic_flag) {
113 unsigned int slice_segment_addr;
114 int slice_address_length;
115
116 if (ps->pps->dependent_slice_segments_enabled_flag)
117 dependent_slice_segment_flag = get_bits1(gb);
118 else
119 dependent_slice_segment_flag = 0;
120
121 slice_address_length = av_ceil_log2_c(ps->sps->ctb_width *
122 ps->sps->ctb_height);
123 slice_segment_addr = get_bitsz(gb, slice_address_length);
124 if (slice_segment_addr >= ps->sps->ctb_width * ps->sps->ctb_height) {
125 av_log(avctx, AV_LOG_ERROR, "Invalid slice segment address: %u.\n",
126 slice_segment_addr);
127 return AVERROR_INVALIDDATA;
128 }
129 } else
130 dependent_slice_segment_flag = 0;
131
132 if (dependent_slice_segment_flag)
133 return 0; /* break; */
134
135 for (i = 0; i < ps->pps->num_extra_slice_header_bits; i++)
136 skip_bits(gb, 1); // slice_reserved_undetermined_flag[]
137
138 slice_type = get_ue_golomb_31(gb);
139 if (!(slice_type == HEVC_SLICE_I || slice_type == HEVC_SLICE_P ||
140 slice_type == HEVC_SLICE_B)) {
141 av_log(avctx, AV_LOG_ERROR, "Unknown slice type: %d.\n",
142 slice_type);
143 return AVERROR_INVALIDDATA;
144 }
145 s->pict_type = slice_type == HEVC_SLICE_B ? AV_PICTURE_TYPE_B :
146 slice_type == HEVC_SLICE_P ? AV_PICTURE_TYPE_P :
147 AV_PICTURE_TYPE_I;
148
149 if (ps->pps->output_flag_present_flag)
150 skip_bits1(gb); // pic_output_flag
151
152 if (ps->sps->separate_colour_plane_flag)
153 skip_bits(gb, 2); // colour_plane_id
154
155 if (!IS_IDR_NAL(nal)) {
156 int pic_order_cnt_lsb = get_bits(gb, ps->sps->log2_max_poc_lsb);
157 s->output_picture_number = ctx->poc =
158 ff_hevc_compute_poc(ps->sps, ctx->pocTid0, pic_order_cnt_lsb, nal->type);
159 } else
160 s->output_picture_number = ctx->poc = 0;
161
162 if (nal->temporal_id == 0 &&
163 nal->type != HEVC_NAL_TRAIL_N &&
164 nal->type != HEVC_NAL_TSA_N &&
165 nal->type != HEVC_NAL_STSA_N &&
166 nal->type != HEVC_NAL_RADL_N &&
167 nal->type != HEVC_NAL_RASL_N &&
168 nal->type != HEVC_NAL_RADL_R &&
169 nal->type != HEVC_NAL_RASL_R)
170 ctx->pocTid0 = ctx->poc;
171
172 return 1; /* no need to evaluate the rest */
173 }
174
175 /**
176 * Parse NAL units of found picture and decode some basic information.
177 *
178 * @param s parser context.
179 * @param avctx codec context.
180 * @param buf buffer with field/frame data.
181 * @param buf_size size of the buffer.
182 */
parse_nal_units(AVCodecParserContext *s, const uint8_t *buf, int buf_size, AVCodecContext *avctx)183 static int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf,
184 int buf_size, AVCodecContext *avctx)
185 {
186 HEVCParserContext *ctx = s->priv_data;
187 HEVCParamSets *ps = &ctx->ps;
188 HEVCSEI *sei = &ctx->sei;
189 int ret, i;
190
191 /* set some sane default values */
192 s->pict_type = AV_PICTURE_TYPE_I;
193 s->key_frame = 0;
194 s->picture_structure = AV_PICTURE_STRUCTURE_UNKNOWN;
195
196 ff_hevc_reset_sei(sei);
197
198 ret = ff_h2645_packet_split(&ctx->pkt, buf, buf_size, avctx, ctx->is_avc,
199 ctx->nal_length_size, AV_CODEC_ID_HEVC, 1, 0);
200 if (ret < 0)
201 return ret;
202
203 for (i = 0; i < ctx->pkt.nb_nals; i++) {
204 H2645NAL *nal = &ctx->pkt.nals[i];
205 GetBitContext *gb = &nal->gb;
206
207 if (nal->nuh_layer_id > 0)
208 continue;
209
210 switch (nal->type) {
211 case HEVC_NAL_VPS:
212 ff_hevc_decode_nal_vps(gb, avctx, ps);
213 break;
214 case HEVC_NAL_SPS:
215 ff_hevc_decode_nal_sps(gb, avctx, ps, 1);
216 break;
217 case HEVC_NAL_PPS:
218 ff_hevc_decode_nal_pps(gb, avctx, ps);
219 break;
220 case HEVC_NAL_SEI_PREFIX:
221 case HEVC_NAL_SEI_SUFFIX:
222 ff_hevc_decode_nal_sei(gb, avctx, sei, ps, nal->type);
223 break;
224 case HEVC_NAL_TRAIL_N:
225 case HEVC_NAL_TRAIL_R:
226 case HEVC_NAL_TSA_N:
227 case HEVC_NAL_TSA_R:
228 case HEVC_NAL_STSA_N:
229 case HEVC_NAL_STSA_R:
230 case HEVC_NAL_BLA_W_LP:
231 case HEVC_NAL_BLA_W_RADL:
232 case HEVC_NAL_BLA_N_LP:
233 case HEVC_NAL_IDR_W_RADL:
234 case HEVC_NAL_IDR_N_LP:
235 case HEVC_NAL_CRA_NUT:
236 case HEVC_NAL_RADL_N:
237 case HEVC_NAL_RADL_R:
238 case HEVC_NAL_RASL_N:
239 case HEVC_NAL_RASL_R:
240 if (ctx->sei.picture_timing.picture_struct == HEVC_SEI_PIC_STRUCT_FRAME_DOUBLING) {
241 s->repeat_pict = 1;
242 } else if (ctx->sei.picture_timing.picture_struct == HEVC_SEI_PIC_STRUCT_FRAME_TRIPLING) {
243 s->repeat_pict = 2;
244 }
245 ret = hevc_parse_slice_header(s, nal, avctx);
246 if (ret)
247 return ret;
248 break;
249 }
250 }
251 /* didn't find a picture! */
252 av_log(avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size);
253 return -1;
254 }
255
256 /**
257 * Find the end of the current frame in the bitstream.
258 * @return the position of the first byte of the next frame, or END_NOT_FOUND
259 */
hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf, int buf_size)260 static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf,
261 int buf_size)
262 {
263 HEVCParserContext *ctx = s->priv_data;
264 ParseContext *pc = &ctx->pc;
265 int i;
266
267 for (i = 0; i < buf_size; i++) {
268 int nut;
269
270 pc->state64 = (pc->state64 << 8) | buf[i];
271
272 if (((pc->state64 >> 3 * 8) & 0xFFFFFF) != START_CODE)
273 continue;
274
275 nut = (pc->state64 >> 2 * 8 + 1) & 0x3F;
276 // Beginning of access unit
277 if ((nut >= HEVC_NAL_VPS && nut <= HEVC_NAL_EOB_NUT) || nut == HEVC_NAL_SEI_PREFIX ||
278 (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) {
279 if (pc->frame_start_found) {
280 pc->frame_start_found = 0;
281 return i - 5;
282 }
283 } else if (nut <= HEVC_NAL_RASL_R ||
284 (nut >= HEVC_NAL_BLA_W_LP && nut <= HEVC_NAL_CRA_NUT)) {
285 int first_slice_segment_in_pic_flag = buf[i] >> 7;
286 if (first_slice_segment_in_pic_flag) {
287 if (!pc->frame_start_found) {
288 pc->frame_start_found = 1;
289 } else { // First slice of next frame found
290 pc->frame_start_found = 0;
291 return i - 5;
292 }
293 }
294 }
295 }
296
297 return END_NOT_FOUND;
298 }
299
hevc_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)300 static int hevc_parse(AVCodecParserContext *s, AVCodecContext *avctx,
301 const uint8_t **poutbuf, int *poutbuf_size,
302 const uint8_t *buf, int buf_size)
303 {
304 int next;
305 HEVCParserContext *ctx = s->priv_data;
306 ParseContext *pc = &ctx->pc;
307 int is_dummy_buf = !buf_size;
308 const uint8_t *dummy_buf = buf;
309
310 if (avctx->extradata && !ctx->parsed_extradata) {
311 ff_hevc_decode_extradata(avctx->extradata, avctx->extradata_size, &ctx->ps, &ctx->sei,
312 &ctx->is_avc, &ctx->nal_length_size, avctx->err_recognition,
313 1, avctx);
314 ctx->parsed_extradata = 1;
315 }
316
317 if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
318 next = buf_size;
319 } else {
320 next = hevc_find_frame_end(s, buf, buf_size);
321 if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
322 *poutbuf = NULL;
323 *poutbuf_size = 0;
324 return buf_size;
325 }
326 }
327
328 is_dummy_buf &= (dummy_buf == buf);
329
330 if (!is_dummy_buf)
331 parse_nal_units(s, buf, buf_size, avctx);
332
333 *poutbuf = buf;
334 *poutbuf_size = buf_size;
335 return next;
336 }
337
hevc_parser_close(AVCodecParserContext *s)338 static void hevc_parser_close(AVCodecParserContext *s)
339 {
340 HEVCParserContext *ctx = s->priv_data;
341
342 ff_hevc_ps_uninit(&ctx->ps);
343 ff_h2645_packet_uninit(&ctx->pkt);
344 ff_hevc_reset_sei(&ctx->sei);
345
346 av_freep(&ctx->pc.buffer);
347 }
348
349 const AVCodecParser ff_hevc_parser = {
350 .codec_ids = { AV_CODEC_ID_HEVC },
351 .priv_data_size = sizeof(HEVCParserContext),
352 .parser_parse = hevc_parse,
353 .parser_close = hevc_parser_close,
354 };
355