2 * H.26L/H.264/AVC/JVT/14496-10/... sei decoding
3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
5 * This file is part of FFmpeg.
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.
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.
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
24 * H.264 / AVC / MPEG4 part10 sei decoding.
25 * @author Michael Niedermayer <michaelni@gmx.at>
36 static const uint8_t sei_num_clock_ts_table
[9]={
37 1, 1, 1, 2, 2, 3, 3, 2, 3
40 void ff_h264_reset_sei(H264Context
*h
) {
41 h
->sei_recovery_frame_cnt
= -1;
42 h
->sei_dpb_output_delay
= 0;
43 h
->sei_cpb_removal_delay
= -1;
44 h
->sei_buffering_period_present
= 0;
47 static int decode_picture_timing(H264Context
*h
){
48 MpegEncContext
* const s
= &h
->s
;
49 if(h
->sps
.nal_hrd_parameters_present_flag
|| h
->sps
.vcl_hrd_parameters_present_flag
){
50 h
->sei_cpb_removal_delay
= get_bits(&s
->gb
, h
->sps
.cpb_removal_delay_length
);
51 h
->sei_dpb_output_delay
= get_bits(&s
->gb
, h
->sps
.dpb_output_delay_length
);
53 if(h
->sps
.pic_struct_present_flag
){
54 unsigned int i
, num_clock_ts
;
55 h
->sei_pic_struct
= get_bits(&s
->gb
, 4);
58 if (h
->sei_pic_struct
> SEI_PIC_STRUCT_FRAME_TRIPLING
)
61 num_clock_ts
= sei_num_clock_ts_table
[h
->sei_pic_struct
];
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 */
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 */
87 if(h
->sps
.time_offset_length
> 0)
88 skip_bits(&s
->gb
, h
->sps
.time_offset_length
); /* time_offset */
92 if(s
->avctx
->debug
& FF_DEBUG_PICT_INFO
)
93 av_log(s
->avctx
, AV_LOG_DEBUG
, "ct_type:%X pic_struct:%d\n", h
->sei_ct_type
, h
->sei_pic_struct
);
98 static int decode_unregistered_user_data(H264Context
*h
, int size
){
99 MpegEncContext
* const s
= &h
->s
;
100 uint8_t user_data
[16+256];
106 for(i
=0; i
<sizeof(user_data
)-1 && i
<size
; i
++){
107 user_data
[i
]= get_bits(&s
->gb
, 8);
111 e
= sscanf(user_data
+16, "x264 - core %d"/*%s - H.264/MPEG-4 AVC codec - Copyleft 2005 - http://www.videolan.org/x264.html*/, &build
);
113 h
->x264_build
= build
;
115 if(s
->avctx
->debug
& FF_DEBUG_BUGS
)
116 av_log(s
->avctx
, AV_LOG_DEBUG
, "user data:\"%s\"\n", user_data
+16);
119 skip_bits(&s
->gb
, 8);
124 static int decode_recovery_point(H264Context
*h
){
125 MpegEncContext
* const s
= &h
->s
;
127 h
->sei_recovery_frame_cnt
= get_ue_golomb(&s
->gb
);
128 skip_bits(&s
->gb
, 4); /* 1b exact_match_flag, 1b broken_link_flag, 2b changing_slice_group_idc */
133 static int decode_buffering_period(H264Context
*h
){
134 MpegEncContext
* const s
= &h
->s
;
139 sps_id
= get_ue_golomb_31(&s
->gb
);
140 if(sps_id
> 31 || !h
->sps_buffers
[sps_id
]) {
141 av_log(h
->s
.avctx
, AV_LOG_ERROR
, "non-existing SPS %d referenced in buffering period\n", sps_id
);
144 sps
= h
->sps_buffers
[sps_id
];
146 // NOTE: This is really so duplicated in the standard... See H.264, D.1.1
147 if (sps
->nal_hrd_parameters_present_flag
) {
148 for (sched_sel_idx
= 0; sched_sel_idx
< sps
->cpb_cnt
; sched_sel_idx
++) {
149 h
->initial_cpb_removal_delay
[sched_sel_idx
] = get_bits(&s
->gb
, sps
->initial_cpb_removal_delay_length
);
150 skip_bits(&s
->gb
, sps
->initial_cpb_removal_delay_length
); // initial_cpb_removal_delay_offset
153 if (sps
->vcl_hrd_parameters_present_flag
) {
154 for (sched_sel_idx
= 0; sched_sel_idx
< sps
->cpb_cnt
; sched_sel_idx
++) {
155 h
->initial_cpb_removal_delay
[sched_sel_idx
] = get_bits(&s
->gb
, sps
->initial_cpb_removal_delay_length
);
156 skip_bits(&s
->gb
, sps
->initial_cpb_removal_delay_length
); // initial_cpb_removal_delay_offset
160 h
->sei_buffering_period_present
= 1;
164 int ff_h264_decode_sei(H264Context
*h
){
165 MpegEncContext
* const s
= &h
->s
;
167 while(get_bits_count(&s
->gb
) + 16 < s
->gb
.size_in_bits
){
172 type
+= show_bits(&s
->gb
, 8);
173 }while(get_bits(&s
->gb
, 8) == 255);
177 size
+= show_bits(&s
->gb
, 8);
178 }while(get_bits(&s
->gb
, 8) == 255);
181 case SEI_TYPE_PIC_TIMING
: // Picture timing SEI
182 if(decode_picture_timing(h
) < 0)
185 case SEI_TYPE_USER_DATA_UNREGISTERED
:
186 if(decode_unregistered_user_data(h
, size
) < 0)
189 case SEI_TYPE_RECOVERY_POINT
:
190 if(decode_recovery_point(h
) < 0)
193 case SEI_BUFFERING_PERIOD
:
194 if(decode_buffering_period(h
) < 0)
198 skip_bits(&s
->gb
, 8*size
);
201 //FIXME check bits here
202 align_get_bits(&s
->gb
);