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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  SPS *sps = &h->sps;
49  int i;
50 
51  for (i = 0; i<MAX_SPS_COUNT; i++)
52  if (!sps->log2_max_frame_num && h->sps_buffers[i])
53  sps = h->sps_buffers[i];
54 
58  }
59  if(sps->pic_struct_present_flag){
60  unsigned int i, num_clock_ts;
61  h->sei_pic_struct = get_bits(&h->gb, 4);
62  h->sei_ct_type = 0;
63 
65  return -1;
66 
67  num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct];
68 
69  for (i = 0 ; i < num_clock_ts ; i++){
70  if(get_bits(&h->gb, 1)){ /* clock_timestamp_flag */
71  unsigned int full_timestamp_flag;
72  h->sei_ct_type |= 1<<get_bits(&h->gb, 2);
73  skip_bits(&h->gb, 1); /* nuit_field_based_flag */
74  skip_bits(&h->gb, 5); /* counting_type */
75  full_timestamp_flag = get_bits(&h->gb, 1);
76  skip_bits(&h->gb, 1); /* discontinuity_flag */
77  skip_bits(&h->gb, 1); /* cnt_dropped_flag */
78  skip_bits(&h->gb, 8); /* n_frames */
79  if(full_timestamp_flag){
80  skip_bits(&h->gb, 6); /* seconds_value 0..59 */
81  skip_bits(&h->gb, 6); /* minutes_value 0..59 */
82  skip_bits(&h->gb, 5); /* hours_value 0..23 */
83  }else{
84  if(get_bits(&h->gb, 1)){ /* seconds_flag */
85  skip_bits(&h->gb, 6); /* seconds_value range 0..59 */
86  if(get_bits(&h->gb, 1)){ /* minutes_flag */
87  skip_bits(&h->gb, 6); /* minutes_value 0..59 */
88  if(get_bits(&h->gb, 1)) /* hours_flag */
89  skip_bits(&h->gb, 5); /* hours_value 0..23 */
90  }
91  }
92  }
93  if(sps->time_offset_length > 0)
94  skip_bits(&h->gb, sps->time_offset_length); /* time_offset */
95  }
96  }
97 
99  av_log(h->avctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n", h->sei_ct_type, h->sei_pic_struct);
100  }
101  return 0;
102 }
103 
105  uint32_t user_identifier;
106  int dtg_active_format;
107 
108  if (size < 7)
109  return -1;
110  size -= 7;
111 
112  skip_bits(&h->gb, 8); // country_code
113  skip_bits(&h->gb, 16); // provider_code
114  user_identifier = get_bits_long(&h->gb, 32);
115 
116  switch (user_identifier) {
117  case 0x44544731: // "DTG1" - AFD_data
118  if (size < 1)
119  return -1;
120  skip_bits(&h->gb, 1);
121  if (get_bits(&h->gb, 1)) {
122  skip_bits(&h->gb, 6);
123  if (size < 2)
124  return -1;
125  skip_bits(&h->gb, 4);
126  dtg_active_format = get_bits(&h->gb, 4);
127  h->avctx->dtg_active_format = dtg_active_format;
128  } else {
129  skip_bits(&h->gb, 6);
130  }
131  break;
132  default:
133  skip_bits(&h->gb, size * 8);
134  break;
135  }
136 
137  return 0;
138 }
139 
141  uint8_t user_data[16+256];
142  int e, build, i;
143 
144  if(size<16)
145  return -1;
146 
147  for(i=0; i<sizeof(user_data)-1 && i<size; i++){
148  user_data[i]= get_bits(&h->gb, 8);
149  }
150 
151  user_data[i]= 0;
152  e= sscanf(user_data+16, "x264 - core %d"/*%s - H.264/MPEG-4 AVC codec - Copyleft 2005 - http://www.videolan.org/x264.html*/, &build);
153  if(e==1 && build>0)
154  h->x264_build= build;
155  if(e==1 && build==1 && !strncmp(user_data+16, "x264 - core 0000", 16))
156  h->x264_build = 67;
157 
158  if(h->avctx->debug & FF_DEBUG_BUGS)
159  av_log(h->avctx, AV_LOG_DEBUG, "user data:\"%s\"\n", user_data+16);
160 
161  for(; i<size; i++)
162  skip_bits(&h->gb, 8);
163 
164  return 0;
165 }
166 
169  skip_bits(&h->gb, 4); /* 1b exact_match_flag, 1b broken_link_flag, 2b changing_slice_group_idc */
170 
171  if(h->avctx->debug & FF_DEBUG_PICT_INFO)
172  av_log(h->avctx, AV_LOG_DEBUG, "sei_recovery_frame_cnt: %d\n", h->sei_recovery_frame_cnt);
173 
174  return 0;
175 }
176 
178  unsigned int sps_id;
179  int sched_sel_idx;
180  SPS *sps;
181 
182  sps_id = get_ue_golomb_31(&h->gb);
183  if(sps_id > 31 || !h->sps_buffers[sps_id]) {
184  av_log(h->avctx, AV_LOG_ERROR, "non-existing SPS %d referenced in buffering period\n", sps_id);
185  return -1;
186  }
187  sps = h->sps_buffers[sps_id];
188 
189  // NOTE: This is really so duplicated in the standard... See H.264, D.1.1
191  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
193  skip_bits(&h->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset
194  }
195  }
197  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
199  skip_bits(&h->gb, sps->initial_cpb_removal_delay_length); // initial_cpb_removal_delay_offset
200  }
201  }
202 
204  return 0;
205 }
206 
208  while (get_bits_left(&h->gb) > 16) {
209  int size, type;
210 
211  type=0;
212  do{
213  if (get_bits_left(&h->gb) < 8)
214  return -1;
215  type+= show_bits(&h->gb, 8);
216  }while(get_bits(&h->gb, 8) == 255);
217 
218  size=0;
219  do{
220  if (get_bits_left(&h->gb) < 8)
221  return -1;
222  size+= show_bits(&h->gb, 8);
223  }while(get_bits(&h->gb, 8) == 255);
224 
226  av_log(h->avctx, AV_LOG_DEBUG, "SEI %d len:%d\n", type, size);
227 
228  switch(type){
229  case SEI_TYPE_PIC_TIMING: // Picture timing SEI
230  if(decode_picture_timing(h) < 0)
231  return -1;
232  break;
234  if(decode_user_data_itu_t_t35(h, size) < 0)
235  return -1;
236  break;
238  if(decode_unregistered_user_data(h, size) < 0)
239  return -1;
240  break;
242  if(decode_recovery_point(h) < 0)
243  return -1;
244  break;
246  if(decode_buffering_period(h) < 0)
247  return -1;
248  break;
249  default:
250  skip_bits(&h->gb, 8*size);
251  }
252 
253  //FIXME check bits here
254  align_get_bits(&h->gb);
255  }
256 
257  return 0;
258 }