Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
28 #include "avcodec.h"
29 #include "golomb.h"
30 #include "h264.h"
31 #include "internal.h"
32 
33 static const uint8_t sei_num_clock_ts_table[9] = {
34  1, 1, 1, 2, 2, 3, 3, 2, 3
35 };
36 
38 {
39  h->sei_recovery_frame_cnt = -1;
40  h->sei_dpb_output_delay = 0;
41  h->sei_cpb_removal_delay = -1;
45 }
46 
48 {
55  }
57  unsigned int i, num_clock_ts;
58 
59  h->sei_pic_struct = get_bits(&h->gb, 4);
60  h->sei_ct_type = 0;
61 
63  return AVERROR_INVALIDDATA;
64 
65  num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct];
66 
67  for (i = 0; i < num_clock_ts; i++) {
68  if (get_bits(&h->gb, 1)) { /* clock_timestamp_flag */
69  unsigned int full_timestamp_flag;
70 
71  h->sei_ct_type |= 1 << get_bits(&h->gb, 2);
72  skip_bits(&h->gb, 1); /* nuit_field_based_flag */
73  skip_bits(&h->gb, 5); /* counting_type */
74  full_timestamp_flag = get_bits(&h->gb, 1);
75  skip_bits(&h->gb, 1); /* discontinuity_flag */
76  skip_bits(&h->gb, 1); /* cnt_dropped_flag */
77  skip_bits(&h->gb, 8); /* n_frames */
78  if (full_timestamp_flag) {
79  skip_bits(&h->gb, 6); /* seconds_value 0..59 */
80  skip_bits(&h->gb, 6); /* minutes_value 0..59 */
81  skip_bits(&h->gb, 5); /* hours_value 0..23 */
82  } else {
83  if (get_bits(&h->gb, 1)) { /* seconds_flag */
84  skip_bits(&h->gb, 6); /* seconds_value range 0..59 */
85  if (get_bits(&h->gb, 1)) { /* minutes_flag */
86  skip_bits(&h->gb, 6); /* minutes_value 0..59 */
87  if (get_bits(&h->gb, 1)) /* hours_flag */
88  skip_bits(&h->gb, 5); /* hours_value 0..23 */
89  }
90  }
91  }
92  if (h->sps.time_offset_length > 0)
93  skip_bits(&h->gb,
94  h->sps.time_offset_length); /* time_offset */
95  }
96  }
97 
98  if (h->avctx->debug & FF_DEBUG_PICT_INFO)
99  av_log(h->avctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n",
100  h->sei_ct_type, h->sei_pic_struct);
101  }
102  return 0;
103 }
104 
106 {
107  uint8_t user_data[16 + 256];
108  int e, build, i;
109 
110  if (size < 16)
111  return AVERROR_INVALIDDATA;
112 
113  for (i = 0; i < sizeof(user_data) - 1 && i < size; i++)
114  user_data[i] = get_bits(&h->gb, 8);
115 
116  user_data[i] = 0;
117  e = sscanf(user_data + 16, "x264 - core %d", &build);
118  if (e == 1 && build > 0)
119  h->x264_build = build;
120 
121  if (h->avctx->debug & FF_DEBUG_BUGS)
122  av_log(h->avctx, AV_LOG_DEBUG, "user data:\"%s\"\n", user_data + 16);
123 
124  for (; i < size; i++)
125  skip_bits(&h->gb, 8);
126 
127  return 0;
128 }
129 
131 {
133 
134  /* 1b exact_match_flag,
135  * 1b broken_link_flag,
136  * 2b changing_slice_group_idc */
137  skip_bits(&h->gb, 4);
138 
139  return 0;
140 }
141 
143 {
144  unsigned int sps_id;
145  int sched_sel_idx;
146  SPS *sps;
147 
148  sps_id = get_ue_golomb_31(&h->gb);
149  if (sps_id > 31 || !h->sps_buffers[sps_id]) {
151  "non-existing SPS %d referenced in buffering period\n", sps_id);
152  return AVERROR_INVALIDDATA;
153  }
154  sps = h->sps_buffers[sps_id];
155 
156  // NOTE: This is really so duplicated in the standard... See H.264, D.1.1
158  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
159  h->initial_cpb_removal_delay[sched_sel_idx] =
161  // initial_cpb_removal_delay_offset
163  }
164  }
166  for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
167  h->initial_cpb_removal_delay[sched_sel_idx] =
169  // initial_cpb_removal_delay_offset
171  }
172  }
173 
175  return 0;
176 }
177 
179 {
180  get_ue_golomb(&h->gb); // frame_packing_arrangement_id
182 
183  if (h->sei_frame_packing_present) {
187 
188  // the following skips: spatial_flipping_flag, frame0_flipped_flag,
189  // field_views_flag, current_frame_is_frame0_flag,
190  // frame0_self_contained_flag, frame1_self_contained_flag
191  skip_bits(&h->gb, 6);
192 
194  skip_bits(&h->gb, 16); // frame[01]_grid_position_[xy]
195  skip_bits(&h->gb, 8); // frame_packing_arrangement_reserved_byte
196  get_ue_golomb(&h->gb); // frame_packing_arrangement_repetition_period
197  }
198  skip_bits1(&h->gb); // frame_packing_arrangement_extension_flag
199 
200  return 0;
201 }
202 
204 {
206 
208  h->sei_hflip = get_bits1(&h->gb); // hor_flip
209  h->sei_vflip = get_bits1(&h->gb); // ver_flip
210 
211  h->sei_anticlockwise_rotation = get_bits(&h->gb, 16);
212  get_ue_golomb(&h->gb); // display_orientation_repetition_period
213  skip_bits1(&h->gb); // display_orientation_extension_flag
214  }
215 
216  return 0;
217 }
218 
220 {
221  while (get_bits_left(&h->gb) > 16) {
222  int size = 0;
223  int type = 0;
224  int ret = 0;
225  int last = 0;
226 
227  while (get_bits_left(&h->gb) >= 8 &&
228  (last = get_bits(&h->gb, 8)) == 255) {
229  type += 255;
230  }
231  type += last;
232 
233  last = 0;
234  while (get_bits_left(&h->gb) >= 8 &&
235  (last = get_bits(&h->gb, 8)) == 255) {
236  size += 255;
237  }
238  size += last;
239 
240  if (size > get_bits_left(&h->gb) / 8) {
241  av_log(h->avctx, AV_LOG_ERROR, "SEI type %d truncated at %d\n",
242  type, get_bits_left(&h->gb));
243  return AVERROR_INVALIDDATA;
244  }
245 
246  switch (type) {
247  case SEI_TYPE_PIC_TIMING: // Picture timing SEI
248  ret = decode_picture_timing(h);
249  if (ret < 0)
250  return ret;
251  break;
253  ret = decode_unregistered_user_data(h, size);
254  if (ret < 0)
255  return ret;
256  break;
258  ret = decode_recovery_point(h);
259  if (ret < 0)
260  return ret;
261  break;
263  ret = decode_buffering_period(h);
264  if (ret < 0)
265  return ret;
266  break;
269  if (ret < 0)
270  return ret;
271  break;
274  if (ret < 0)
275  return ret;
276  break;
277  default:
278  av_log(h->avctx, AV_LOG_DEBUG, "unknown SEI type %d\n", type);
279  skip_bits(&h->gb, 8 * size);
280  }
281 
282  // FIXME check bits here
283  align_get_bits(&h->gb);
284  }
285 
286  return 0;
287 }
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
GetBitContext gb
Definition: h264.h:311
int sei_cpb_removal_delay
cpb_removal_delay in picture timing SEI message, see H.264 C.1.2
Definition: h264.h:659
int size
int quincunx_subsampling
Definition: h264.h:635
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:240
unregistered user data
Definition: h264.h:132
Sequence parameter set.
Definition: h264.h:156
int initial_cpb_removal_delay[32]
Initial timestamps for CPBs.
Definition: h264.h:696
H264Context.
Definition: h264.h:303
void ff_h264_reset_sei(H264Context *h)
Reset SEI values at the beginning of the frame.
Definition: h264_sei.c:37
uint8_t
static int decode_picture_timing(H264Context *h)
Definition: h264_sei.c:47
#define FF_DEBUG_PICT_INFO
Definition: avcodec.h:2357
int sei_vflip
Definition: h264.h:642
H.264 / AVC / MPEG4 part10 codec.
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:555
static int decode_unregistered_user_data(H264Context *h, int size)
Definition: h264_sei.c:105
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
static int get_ue_golomb(GetBitContext *gb)
read unsigned exp golomb code.
Definition: golomb.h:53
int time_offset_length
Definition: h264.h:204
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:144
#define FF_DEBUG_BUGS
Definition: avcodec.h:2376
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
int sei_anticlockwise_rotation
Definition: h264.h:641
int initial_cpb_removal_delay_length
initial_cpb_removal_delay_length_minus1 + 1
Definition: h264.h:206
int x264_build
Definition: h264.h:496
int sei_frame_packing_present
frame_packing_arrangment SEI message
Definition: h264.h:632
static int decode_recovery_point(H264Context *h)
Definition: h264_sei.c:130
SPS sps
current sps
Definition: h264.h:401
int sei_hflip
Definition: h264.h:642
static int decode_display_orientation(H264Context *h)
Definition: h264_sei.c:203
frame packing arrangement
Definition: h264.h:134
SPS * sps_buffers[MAX_SPS_COUNT]
Definition: h264.h:532
int vcl_hrd_parameters_present_flag
Definition: h264.h:202
AVCodecContext * avctx
Definition: h264.h:304
Libavcodec external API header.
static int get_ue_golomb_31(GetBitContext *gb)
read unsigned exp golomb code, constraint to a max of 31.
Definition: golomb.h:96
int debug
debug
Definition: avcodec.h:2356
int dpb_output_delay_length
dpb_output_delay_length_minus1 + 1
Definition: h264.h:208
int frame_packing_arrangement_type
Definition: h264.h:633
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:271
SEI_PicStructType sei_pic_struct
pic_struct in picture timing SEI message
Definition: h264.h:619
static void skip_bits1(GetBitContext *s)
Definition: get_bits.h:296
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:263
display orientation
Definition: h264.h:135
int sei_buffering_period_present
Buffering period SEI flag.
Definition: h264.h:695
static const uint8_t sei_num_clock_ts_table[9]
Definition: h264_sei.c:33
int pic_struct_present_flag
Definition: h264.h:203
picture timing
Definition: h264.h:131
common internal api header.
int nal_hrd_parameters_present_flag
Definition: h264.h:201
static int decode_buffering_period(H264Context *h)
Definition: h264_sei.c:142
int sei_ct_type
Bit set of clock types for fields/frames in picture timing SEI message.
Definition: h264.h:649
int ff_h264_decode_sei(H264Context *h)
Decode SEI.
Definition: h264_sei.c:219
int sei_display_orientation_present
display orientation SEI message
Definition: h264.h:640
int content_interpretation_type
Definition: h264.h:634
static const uint8_t * align_get_bits(GetBitContext *s)
Definition: get_bits.h:416
buffering period (H.264, D.1.1)
Definition: h264.h:130
int cpb_cnt
See H.264 E.1.2.
Definition: h264.h:205
int cpb_removal_delay_length
cpb_removal_delay_length_minus1 + 1
Definition: h264.h:207
8: frame tripling
Definition: h264.h:150
exp golomb vlc stuff
int sei_recovery_frame_cnt
recovery_frame_cnt from SEI message
Definition: h264.h:668
int sei_dpb_output_delay
dpb_output_delay in picture timing SEI message, see H.264 C.2.2
Definition: h264.h:654
recovery point (frame # to decoder sync)
Definition: h264.h:133
static int decode_frame_packing_arrangement(H264Context *h)
Definition: h264_sei.c:178