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h264_sei.c
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1 /*
2  * H.26L/H.264/AVC/JVT/14496-10/... sei decoding
3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * H.264 / AVC / MPEG4 part10 sei decoding.
25  * @author Michael Niedermayer <michaelni@gmx.at>
26  */
27 
28 #include "internal.h"
29 #include "avcodec.h"
30 #include "h264.h"
31 #include "golomb.h"
32 
33 //#undef NDEBUG
34 #include <assert.h>
35 
37  1, 1, 1, 2, 2, 3, 3, 2, 3
38 };
39 
41  h->sei_recovery_frame_cnt = -1;
42  h->sei_dpb_output_delay = 0;
43  h->sei_cpb_removal_delay = -1;
45 }
46 
48  MpegEncContext * const s = &h->s;
52  }
54  unsigned int i, num_clock_ts;
55  h->sei_pic_struct = get_bits(&s->gb, 4);
56  h->sei_ct_type = 0;
57 
59  return -1;
60 
61  num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct];
62 
63  for (i = 0 ; i < num_clock_ts ; i++){
64  if(get_bits(&s->gb, 1)){ /* clock_timestamp_flag */
65  unsigned int full_timestamp_flag;
66  h->sei_ct_type |= 1<<get_bits(&s->gb, 2);
67  skip_bits(&s->gb, 1); /* nuit_field_based_flag */
68  skip_bits(&s->gb, 5); /* counting_type */
69  full_timestamp_flag = get_bits(&s->gb, 1);
70  skip_bits(&s->gb, 1); /* discontinuity_flag */
71  skip_bits(&s->gb, 1); /* cnt_dropped_flag */
72  skip_bits(&s->gb, 8); /* n_frames */
73  if(full_timestamp_flag){
74  skip_bits(&s->gb, 6); /* seconds_value 0..59 */
75  skip_bits(&s->gb, 6); /* minutes_value 0..59 */
76  skip_bits(&s->gb, 5); /* hours_value 0..23 */
77  }else{
78  if(get_bits(&s->gb, 1)){ /* seconds_flag */
79  skip_bits(&s->gb, 6); /* seconds_value range 0..59 */
80  if(get_bits(&s->gb, 1)){ /* minutes_flag */
81  skip_bits(&s->gb, 6); /* minutes_value 0..59 */
82  if(get_bits(&s->gb, 1)) /* hours_flag */
83  skip_bits(&s->gb, 5); /* hours_value 0..23 */
84  }
85  }
86  }
87  if(h->sps.time_offset_length > 0)
88  skip_bits(&s->gb, h->sps.time_offset_length); /* time_offset */
89  }
90  }
91 
93  av_log(s->avctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n", h->sei_ct_type, h->sei_pic_struct);
94  }
95  return 0;
96 }
97 
99  MpegEncContext * const s = &h->s;
100  uint32_t user_identifier;
101  int dtg_active_format;
102 
103  if (size < 7)
104  return -1;
105  size -= 7;
106 
107  skip_bits(&s->gb, 8); // country_code
108  skip_bits(&s->gb, 16); // provider_code
109  user_identifier = get_bits_long(&s->gb, 32);
110 
111  switch (user_identifier) {
112  case 0x44544731: // "DTG1" - AFD_data
113  if (size < 1)
114  return -1;
115  skip_bits(&s->gb, 1);
116  if (get_bits(&s->gb, 1)) {
117  skip_bits(&s->gb, 6);
118  if (size < 2)
119  return -1;
120  skip_bits(&s->gb, 4);
121  dtg_active_format = get_bits(&s->gb, 4);
122  s->avctx->dtg_active_format = dtg_active_format;
123  } else {
124  skip_bits(&s->gb, 6);
125  }
126  break;
127  default:
128  skip_bits(&s->gb, size * 8);
129  break;
130  }
131 
132  return 0;
133 }
134 
136  MpegEncContext * const s = &h->s;
137  uint8_t user_data[16+256];
138  int e, build, i;
139 
140  if(size<16)
141  return -1;
142 
143  for(i=0; i<sizeof(user_data)-1 && i<size; i++){
144  user_data[i]= get_bits(&s->gb, 8);
145  }
146 
147  user_data[i]= 0;
148  e= sscanf(user_data+16, "x264 - core %d"/*%s - H.264/MPEG-4 AVC codec - Copyleft 2005 - http://www.videolan.org/x264.html*/, &build);
149  if(e==1 && build>0)
150  h->x264_build= build;
151  if(e==1 && build==1 && !strncmp(user_data+16, "x264 - core 0000", 16))
152  h->x264_build = 67;
153 
154  if(s->avctx->debug & FF_DEBUG_BUGS)
155  av_log(s->avctx, AV_LOG_DEBUG, "user data:\"%s\"\n", user_data+16);
156 
157  for(; i<size; i++)
158  skip_bits(&s->gb, 8);
159 
160  return 0;
161 }
162 
164  MpegEncContext * const s = &h->s;
165 
167  skip_bits(&s->gb, 4); /* 1b exact_match_flag, 1b broken_link_flag, 2b changing_slice_group_idc */
168 
169  return 0;
170 }
171 
173  MpegEncContext * const s = &h->s;
174  unsigned int sps_id;
175  int sched_sel_idx;
176  SPS *sps;
177 
178  sps_id = get_ue_golomb_31(&s->gb);
179  if(sps_id > 31 || !h->sps_buffers[sps_id]) {
180  av_log(h->s.avctx, AV_LOG_ERROR, "non-existing SPS %d referenced in buffering period\n", sps_id);
181  return -1;
182  }
183  sps = h->sps_buffers[sps_id];
184 
185  // NOTE: This is really so duplicated in the standard... See H.264, D.1.1
187  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
189  skip_bits(&s->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset
190  }
191  }
193  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
195  skip_bits(&s->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset
196  }
197  }
198 
200  return 0;
201 }
202 
204  MpegEncContext * const s = &h->s;
205 
206  while (get_bits_left(&s->gb) > 16) {
207  int size, type;
208 
209  type=0;
210  do{
211  if (get_bits_left(&s->gb) < 8)
212  return -1;
213  type+= show_bits(&s->gb, 8);
214  }while(get_bits(&s->gb, 8) == 255);
215 
216  size=0;
217  do{
218  if (get_bits_left(&s->gb) < 8)
219  return -1;
220  size+= show_bits(&s->gb, 8);
221  }while(get_bits(&s->gb, 8) == 255);
222 
224  av_log(h->s.avctx, AV_LOG_DEBUG, "SEI %d len:%d\n", type, size);
225 
226  switch(type){
227  case SEI_TYPE_PIC_TIMING: // Picture timing SEI
228  if(decode_picture_timing(h) < 0)
229  return -1;
230  break;
232  if(decode_user_data_itu_t_t35(h, size) < 0)
233  return -1;
234  break;
236  if(decode_unregistered_user_data(h, size) < 0)
237  return -1;
238  break;
240  if(decode_recovery_point(h) < 0)
241  return -1;
242  break;
244  if(decode_buffering_period(h) < 0)
245  return -1;
246  break;
247  default:
248  skip_bits(&s->gb, 8*size);
249  }
250 
251  //FIXME check bits here
252  align_get_bits(&s->gb);
253  }
254 
255  return 0;
256 }