FFmpeg
hevc_parser.c
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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 "internal.h"
32 #include "parser.h"
33 
34 #define START_CODE 0x000001 ///< start_code_prefix_one_3bytes
35 
36 #define IS_IRAP_NAL(nal) (nal->type >= 16 && nal->type <= 23)
37 #define IS_IDR_NAL(nal) (nal->type == HEVC_NAL_IDR_W_RADL || nal->type == HEVC_NAL_IDR_N_LP)
38 
39 typedef struct HEVCParserContext {
41 
45 
46  int is_avc;
49 
50  int poc;
51  int pocTid0;
53 
55  AVCodecContext *avctx)
56 {
58  HEVCParamSets *ps = &ctx->ps;
59  HEVCSEI *sei = &ctx->sei;
60  GetBitContext *gb = &nal->gb;
61  const HEVCWindow *ow;
62  int i, num = 0, den = 0;
63 
64  unsigned int pps_id, first_slice_in_pic_flag, dependent_slice_segment_flag;
65  enum HEVCSliceType slice_type;
66 
67  first_slice_in_pic_flag = get_bits1(gb);
70 
71  if (IS_IRAP_NAL(nal)) {
72  s->key_frame = 1;
73  skip_bits1(gb); // no_output_of_prior_pics_flag
74  }
75 
76  pps_id = get_ue_golomb(gb);
77  if (pps_id >= HEVC_MAX_PPS_COUNT || !ps->pps_list[pps_id]) {
78  av_log(avctx, AV_LOG_ERROR, "PPS id out of range: %d\n", pps_id);
79  return AVERROR_INVALIDDATA;
80  }
81  ps->pps = (HEVCPPS*)ps->pps_list[pps_id]->data;
82 
83  if (ps->pps->sps_id >= HEVC_MAX_SPS_COUNT || !ps->sps_list[ps->pps->sps_id]) {
84  av_log(avctx, AV_LOG_ERROR, "SPS id out of range: %d\n", ps->pps->sps_id);
85  return AVERROR_INVALIDDATA;
86  }
87  if (ps->sps != (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data) {
88  ps->sps = (HEVCSPS*)ps->sps_list[ps->pps->sps_id]->data;
89  ps->vps = (HEVCVPS*)ps->vps_list[ps->sps->vps_id]->data;
90  }
91  ow = &ps->sps->output_window;
92 
93  s->coded_width = ps->sps->width;
94  s->coded_height = ps->sps->height;
95  s->width = ps->sps->width - ow->left_offset - ow->right_offset;
96  s->height = ps->sps->height - ow->top_offset - ow->bottom_offset;
97  s->format = ps->sps->pix_fmt;
98  avctx->profile = ps->sps->ptl.general_ptl.profile_idc;
99  avctx->level = ps->sps->ptl.general_ptl.level_idc;
100 
102  num = ps->vps->vps_num_units_in_tick;
103  den = ps->vps->vps_time_scale;
104  } else if (ps->sps->vui.vui_timing_info_present_flag) {
105  num = ps->sps->vui.vui_num_units_in_tick;
106  den = ps->sps->vui.vui_time_scale;
107  }
108 
109  if (num != 0 && den != 0)
110  av_reduce(&avctx->framerate.den, &avctx->framerate.num,
111  num, den, 1 << 30);
112 
113  if (!first_slice_in_pic_flag) {
114  unsigned int slice_segment_addr;
115  int slice_address_length;
116 
118  dependent_slice_segment_flag = get_bits1(gb);
119  else
120  dependent_slice_segment_flag = 0;
121 
122  slice_address_length = av_ceil_log2_c(ps->sps->ctb_width *
123  ps->sps->ctb_height);
124  slice_segment_addr = get_bitsz(gb, slice_address_length);
125  if (slice_segment_addr >= ps->sps->ctb_width * ps->sps->ctb_height) {
126  av_log(avctx, AV_LOG_ERROR, "Invalid slice segment address: %u.\n",
127  slice_segment_addr);
128  return AVERROR_INVALIDDATA;
129  }
130  } else
131  dependent_slice_segment_flag = 0;
132 
133  if (dependent_slice_segment_flag)
134  return 0; /* break; */
135 
136  for (i = 0; i < ps->pps->num_extra_slice_header_bits; i++)
137  skip_bits(gb, 1); // slice_reserved_undetermined_flag[]
138 
139  slice_type = get_ue_golomb_31(gb);
140  if (!(slice_type == HEVC_SLICE_I || slice_type == HEVC_SLICE_P ||
141  slice_type == HEVC_SLICE_B)) {
142  av_log(avctx, AV_LOG_ERROR, "Unknown slice type: %d.\n",
143  slice_type);
144  return AVERROR_INVALIDDATA;
145  }
146  s->pict_type = slice_type == HEVC_SLICE_B ? AV_PICTURE_TYPE_B :
147  slice_type == HEVC_SLICE_P ? AV_PICTURE_TYPE_P :
149 
150  if (ps->pps->output_flag_present_flag)
151  skip_bits1(gb); // pic_output_flag
152 
154  skip_bits(gb, 2); // colour_plane_id
155 
156  if (!IS_IDR_NAL(nal)) {
157  int pic_order_cnt_lsb = get_bits(gb, ps->sps->log2_max_poc_lsb);
158  s->output_picture_number = ctx->poc =
159  ff_hevc_compute_poc(ps->sps, ctx->pocTid0, pic_order_cnt_lsb, nal->type);
160  } else
161  s->output_picture_number = ctx->poc = 0;
162 
163  if (nal->temporal_id == 0 &&
164  nal->type != HEVC_NAL_TRAIL_N &&
165  nal->type != HEVC_NAL_TSA_N &&
166  nal->type != HEVC_NAL_STSA_N &&
167  nal->type != HEVC_NAL_RADL_N &&
168  nal->type != HEVC_NAL_RASL_N &&
169  nal->type != HEVC_NAL_RADL_R &&
170  nal->type != HEVC_NAL_RASL_R)
171  ctx->pocTid0 = ctx->poc;
172 
173  return 1; /* no need to evaluate the rest */
174 }
175 
176 /**
177  * Parse NAL units of found picture and decode some basic information.
178  *
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.
183  */
185  int buf_size, AVCodecContext *avctx)
186 {
188  HEVCParamSets *ps = &ctx->ps;
189  HEVCSEI *sei = &ctx->sei;
190  int ret, i;
191 
192  /* set some sane default values */
194  s->key_frame = 0;
196 
197  ff_hevc_reset_sei(sei);
198 
199  ret = ff_h2645_packet_split(&ctx->pkt, buf, buf_size, avctx, ctx->is_avc,
200  ctx->nal_length_size, AV_CODEC_ID_HEVC, 1, 0);
201  if (ret < 0)
202  return ret;
203 
204  for (i = 0; i < ctx->pkt.nb_nals; i++) {
205  H2645NAL *nal = &ctx->pkt.nals[i];
206  GetBitContext *gb = &nal->gb;
207 
208  if (nal->nuh_layer_id > 0)
209  continue;
210 
211  switch (nal->type) {
212  case HEVC_NAL_VPS:
213  ff_hevc_decode_nal_vps(gb, avctx, ps);
214  break;
215  case HEVC_NAL_SPS:
216  ff_hevc_decode_nal_sps(gb, avctx, ps, 1);
217  break;
218  case HEVC_NAL_PPS:
219  ff_hevc_decode_nal_pps(gb, avctx, ps);
220  break;
221  case HEVC_NAL_SEI_PREFIX:
222  case HEVC_NAL_SEI_SUFFIX:
223  ff_hevc_decode_nal_sei(gb, avctx, sei, ps, nal->type);
224  break;
225  case HEVC_NAL_TRAIL_N:
226  case HEVC_NAL_TRAIL_R:
227  case HEVC_NAL_TSA_N:
228  case HEVC_NAL_TSA_R:
229  case HEVC_NAL_STSA_N:
230  case HEVC_NAL_STSA_R:
231  case HEVC_NAL_BLA_W_LP:
232  case HEVC_NAL_BLA_W_RADL:
233  case HEVC_NAL_BLA_N_LP:
234  case HEVC_NAL_IDR_W_RADL:
235  case HEVC_NAL_IDR_N_LP:
236  case HEVC_NAL_CRA_NUT:
237  case HEVC_NAL_RADL_N:
238  case HEVC_NAL_RADL_R:
239  case HEVC_NAL_RASL_N:
240  case HEVC_NAL_RASL_R:
242  s->repeat_pict = 1;
244  s->repeat_pict = 2;
245  }
246  ret = hevc_parse_slice_header(s, nal, avctx);
247  if (ret)
248  return ret;
249  break;
250  }
251  }
252  /* didn't find a picture! */
253  av_log(avctx, AV_LOG_ERROR, "missing picture in access unit with size %d\n", buf_size);
254  return -1;
255 }
256 
257 /**
258  * Find the end of the current frame in the bitstream.
259  * @return the position of the first byte of the next frame, or END_NOT_FOUND
260  */
262  int buf_size)
263 {
265  ParseContext *pc = &ctx->pc;
266  int i;
267 
268  for (i = 0; i < buf_size; i++) {
269  int nut;
270 
271  pc->state64 = (pc->state64 << 8) | buf[i];
272 
273  if (((pc->state64 >> 3 * 8) & 0xFFFFFF) != START_CODE)
274  continue;
275 
276  nut = (pc->state64 >> 2 * 8 + 1) & 0x3F;
277  // Beginning of access unit
278  if ((nut >= HEVC_NAL_VPS && nut <= HEVC_NAL_EOB_NUT) || nut == HEVC_NAL_SEI_PREFIX ||
279  (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) {
280  if (pc->frame_start_found) {
281  pc->frame_start_found = 0;
282  return i - 5;
283  }
284  } else if (nut <= HEVC_NAL_RASL_R ||
285  (nut >= HEVC_NAL_BLA_W_LP && nut <= HEVC_NAL_CRA_NUT)) {
286  int first_slice_segment_in_pic_flag = buf[i] >> 7;
287  if (first_slice_segment_in_pic_flag) {
288  if (!pc->frame_start_found) {
289  pc->frame_start_found = 1;
290  } else { // First slice of next frame found
291  pc->frame_start_found = 0;
292  return i - 5;
293  }
294  }
295  }
296  }
297 
298  return END_NOT_FOUND;
299 }
300 
302  const uint8_t **poutbuf, int *poutbuf_size,
303  const uint8_t *buf, int buf_size)
304 {
305  int next;
307  ParseContext *pc = &ctx->pc;
308  int is_dummy_buf = !buf_size;
309  const uint8_t *dummy_buf = buf;
310 
311  if (avctx->extradata && !ctx->parsed_extradata) {
312  ff_hevc_decode_extradata(avctx->extradata, avctx->extradata_size, &ctx->ps, &ctx->sei,
313  &ctx->is_avc, &ctx->nal_length_size, avctx->err_recognition,
314  1, avctx);
315  ctx->parsed_extradata = 1;
316  }
317 
319  next = buf_size;
320  } else {
321  next = hevc_find_frame_end(s, buf, buf_size);
322  if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
323  *poutbuf = NULL;
324  *poutbuf_size = 0;
325  return buf_size;
326  }
327  }
328 
329  is_dummy_buf &= (dummy_buf == buf);
330 
331  if (!is_dummy_buf)
332  parse_nal_units(s, buf, buf_size, avctx);
333 
334  *poutbuf = buf;
335  *poutbuf_size = buf_size;
336  return next;
337 }
338 
339 // Split after the parameter sets at the beginning of the stream if they exist.
340 static int hevc_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
341 {
342  const uint8_t *ptr = buf, *end = buf + buf_size;
343  uint32_t state = -1;
344  int has_vps = 0;
345  int has_sps = 0;
346  int has_pps = 0;
347  int nut;
348 
349  while (ptr < end) {
350  ptr = avpriv_find_start_code(ptr, end, &state);
351  if ((state >> 8) != START_CODE)
352  break;
353  nut = (state >> 1) & 0x3F;
354  if (nut == HEVC_NAL_VPS)
355  has_vps = 1;
356  else if (nut == HEVC_NAL_SPS)
357  has_sps = 1;
358  else if (nut == HEVC_NAL_PPS)
359  has_pps = 1;
360  else if ((nut != HEVC_NAL_SEI_PREFIX || has_pps) &&
361  nut != HEVC_NAL_AUD) {
362  if (has_vps && has_sps) {
363  while (ptr - 4 > buf && ptr[-5] == 0)
364  ptr--;
365  return ptr - 4 - buf;
366  }
367  }
368  }
369  return 0;
370 }
371 
373 {
375 
376  ff_hevc_ps_uninit(&ctx->ps);
378  ff_hevc_reset_sei(&ctx->sei);
379 
380  av_freep(&ctx->pc.buffer);
381 }
382 
385  .priv_data_size = sizeof(HEVCParserContext),
386  .parser_parse = hevc_parse,
387  .parser_close = hevc_parser_close,
388  .split = hevc_split,
389 };
const HEVCPPS * pps
Definition: hevc_ps.h:335
#define NULL
Definition: coverity.c:32
AVRational framerate
Definition: avcodec.h:2081
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
static int hevc_parse_slice_header(AVCodecParserContext *s, H2645NAL *nal, AVCodecContext *avctx)
Definition: hevc_parser.c:54
int ctb_height
Definition: hevc_ps.h:230
AVBufferRef * vps_list[HEVC_MAX_VPS_COUNT]
Definition: hevc_ps.h:328
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
static int hevc_split(AVCodecContext *avctx, const uint8_t *buf, int buf_size)
Definition: hevc_parser.c:340
int width
Dimensions of the decoded video intended for presentation.
Definition: avcodec.h:3512
VUI vui
Definition: hevc_ps.h:178
enum AVFieldOrder field_order
Definition: avcodec.h:3489
int num
Numerator.
Definition: rational.h:59
uint32_t vui_time_scale
Definition: hevc_ps.h:76
int codec_ids[5]
Definition: avcodec.h:3533
int coded_width
Dimensions of the coded video.
Definition: avcodec.h:3518
unsigned int left_offset
Definition: hevc_ps.h:43
H.265 parser code.
H2645Packet pkt
Definition: hevc_parser.c:42
int ff_hevc_decode_extradata(const uint8_t *data, int size, HEVCParamSets *ps, HEVCSEI *sei, int *is_nalff, int *nal_length_size, int err_recognition, int apply_defdispwin, void *logctx)
Definition: hevc_parse.c:80
int profile
profile
Definition: avcodec.h:1871
int frame_start_found
Definition: parser.h:34
int width
Definition: hevc_ps.h:227
HEVCWindow output_window
Definition: hevc_ps.h:158
AVBufferRef * sps_list[HEVC_MAX_SPS_COUNT]
Definition: hevc_ps.h:329
enum AVPictureStructure picture_structure
Indicate whether a picture is coded as a frame, top field or bottom field.
Definition: avcodec.h:3499
uint8_t
uint8_t vps_timing_info_present_flag
Definition: hevc_ps.h:135
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:92
const HEVCVPS * vps
Definition: hevc_ps.h:333
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:632
int ff_h2645_packet_split(H2645Packet *pkt, const uint8_t *buf, int length, void *logctx, int is_nalff, int nal_length_size, enum AVCodecID codec_id, int small_padding, int use_ref)
Split an input packet into NAL units.
Definition: h2645_parse.c:392
void ff_h2645_packet_uninit(H2645Packet *pkt)
Free all the allocated memory in the packet.
Definition: h2645_parse.c:523
AVBufferRef * pps_list[HEVC_MAX_PPS_COUNT]
Definition: hevc_ps.h:330
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
#define av_log(a,...)
const uint8_t * avpriv_find_start_code(const uint8_t *p, const uint8_t *end, uint32_t *state)
HEVCParamSets ps
Definition: hevc_parser.c:43
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static int get_ue_golomb(GetBitContext *gb)
Read an unsigned Exp-Golomb code in the range 0 to 8190.
Definition: golomb.h:55
unsigned int log2_max_poc_lsb
Definition: hevc_ps.h:167
int ff_hevc_compute_poc(const HEVCSPS *sps, int pocTid0, int poc_lsb, int nal_unit_type)
Compute POC of the current frame and return it.
Definition: hevc_ps.c:1759
int ff_hevc_decode_nal_vps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps)
Definition: hevc_ps.c:458
int ff_combine_frame(ParseContext *pc, int next, const uint8_t **buf, int *buf_size)
Combine the (truncated) bitstream to a complete frame.
Definition: parser.c:234
int vui_timing_info_present_flag
Definition: hevc_ps.h:74
static int hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf, int buf_size)
Find the end of the current frame in the bitstream.
Definition: hevc_parser.c:261
static char * split(char *message, char delim)
Definition: af_channelmap.c:81
static int parse_nal_units(AVCodecParserContext *s, const uint8_t *buf, int buf_size, AVCodecContext *avctx)
Parse NAL units of found picture and decode some basic information.
Definition: hevc_parser.c:184
uint32_t vps_num_units_in_tick
Definition: hevc_ps.h:136
const HEVCSPS * sps
Definition: hevc_ps.h:334
uint8_t profile_idc
Definition: hevc_ps.h:95
int err_recognition
Error recognition; may misdetect some more or less valid parts as errors.
Definition: avcodec.h:1660
unsigned int top_offset
Definition: hevc_ps.h:45
AVFormatContext * ctx
Definition: movenc.c:48
#define s(width, name)
Definition: cbs_vp9.c:257
int level
level
Definition: avcodec.h:1994
#define IS_IDR_NAL(nal)
Definition: hevc_parser.c:37
int ctb_width
Definition: hevc_ps.h:229
int height
Definition: hevc_ps.h:228
uint8_t output_flag_present_flag
Definition: hevc_ps.h:271
PTLCommon general_ptl
Definition: hevc_ps.h:116
int type
NAL unit type.
Definition: h2645_parse.h:52
#define IS_IRAP_NAL(nal)
Definition: hevc_parser.c:36
unsigned vps_id
Definition: hevc_ps.h:154
ParseContext pc
Definition: hevc_parser.c:40
if(ret)
uint32_t vps_time_scale
Definition: hevc_ps.h:137
void ff_hevc_ps_uninit(HEVCParamSets *ps)
Definition: hevc_ps.c:1743
enum AVPixelFormat pix_fmt
Definition: hevc_ps.h:165
uint8_t * buffer
Definition: parser.h:29
void ff_hevc_reset_sei(HEVCSEI *s)
Reset SEI values that are stored on the Context.
Definition: hevc_sei.c:415
static int get_ue_golomb_31(GetBitContext *gb)
read unsigned exp golomb code, constraint to a max of 31.
Definition: golomb.h:122
PTL ptl
Definition: hevc_ps.h:179
#define START_CODE
start_code_prefix_one_3bytes
Definition: hevc_parser.c:34
unsigned int sps_id
seq_parameter_set_id
Definition: hevc_ps.h:250
main external API structure.
Definition: avcodec.h:531
int num_extra_slice_header_bits
Definition: hevc_ps.h:296
uint8_t * data
The data buffer.
Definition: buffer.h:89
AVCodecParser ff_hevc_parser
Definition: hevc_parser.c:383
uint32_t vui_num_units_in_tick
Definition: hevc_ps.h:75
int extradata_size
Definition: avcodec.h:633
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:498
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:538
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
uint64_t state64
contains the last 8 bytes in MSB order
Definition: parser.h:37
int ff_hevc_decode_nal_pps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps)
Definition: hevc_ps.c:1495
#define END_NOT_FOUND
Definition: parser.h:40
int ff_hevc_decode_nal_sps(GetBitContext *gb, AVCodecContext *avctx, HEVCParamSets *ps, int apply_defdispwin)
Definition: hevc_ps.c:1246
int output_picture_number
Picture number incremented in presentation or output order.
Definition: avcodec.h:3507
HEVCSEIPictureTiming picture_timing
Definition: hevc_sei.h:142
uint8_t level_idc
Definition: hevc_ps.h:112
HEVCSliceType
Definition: hevc.h:95
common internal api header.
common internal and external API header
static struct @323 state
Bi-dir predicted.
Definition: avutil.h:276
#define PARSER_FLAG_COMPLETE_FRAMES
Definition: avcodec.h:3399
int den
Denominator.
Definition: rational.h:60
GetBitContext gb
Definition: h2645_parse.h:47
int format
The format of the coded data, corresponds to enum AVPixelFormat for video and for enum AVSampleFormat...
Definition: avcodec.h:3529
H2645NAL * nals
Definition: h2645_parse.h:82
int temporal_id
HEVC only, nuh_temporal_id_plus_1 - 1.
Definition: h2645_parse.h:57
int repeat_pict
This field is used for proper frame duration computation in lavf.
Definition: avcodec.h:3383
unsigned int right_offset
Definition: hevc_ps.h:44
static int hevc_parse(AVCodecParserContext *s, AVCodecContext *avctx, const uint8_t **poutbuf, int *poutbuf_size, const uint8_t *buf, int buf_size)
Definition: hevc_parser.c:301
#define av_freep(p)
int nuh_layer_id
Definition: h2645_parse.h:62
static void hevc_parser_close(AVCodecParserContext *s)
Definition: hevc_parser.c:372
static av_always_inline av_const int av_ceil_log2_c(int x)
Compute ceil(log2(x)).
Definition: common.h:371
exp golomb vlc stuff
int key_frame
Set by parser to 1 for key frames and 0 for non-key frames.
Definition: avcodec.h:3414
int ff_hevc_decode_nal_sei(GetBitContext *gb, void *logctx, HEVCSEI *s, const HEVCParamSets *ps, int type)
Definition: hevc_sei.c:402
uint8_t separate_colour_plane_flag
Definition: hevc_ps.h:156
int i
Definition: input.c:407
static av_always_inline int get_bitsz(GetBitContext *s, int n)
Read 0-25 bits.
Definition: get_bits.h:415
Predicted.
Definition: avutil.h:275
unsigned int bottom_offset
Definition: hevc_ps.h:46
uint8_t dependent_slice_segments_enabled_flag
Definition: hevc_ps.h:274