avcodec/h264_sei: ff_h264_decode_sei: dont try to parse trailing zeroes
[ffmpeg.git] / libavcodec / h264_sei.c
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 "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
37 void ff_h264_reset_sei(H264Context *h)
38 {
39     h->sei_recovery_frame_cnt       = -1;
40     h->sei_dpb_output_delay         =  0;
41     h->sei_cpb_removal_delay        = -1;
42     h->sei_buffering_period_present =  0;
43     h->sei_frame_packing_present    =  0;
44     h->sei_display_orientation_present = 0;
45 }
46
47 static int decode_picture_timing(H264Context *h)
48 {
49     SPS *sps = &h->sps;
50     int i;
51
52     for (i = 0; i<MAX_SPS_COUNT; i++)
53         if (!sps->log2_max_frame_num && h->sps_buffers[i])
54             sps = h->sps_buffers[i];
55
56     if (sps->nal_hrd_parameters_present_flag || sps->vcl_hrd_parameters_present_flag) {
57         h->sei_cpb_removal_delay = get_bits_long(&h->gb,
58                                                  sps->cpb_removal_delay_length);
59         h->sei_dpb_output_delay  = get_bits_long(&h->gb,
60                                                  sps->dpb_output_delay_length);
61     }
62     if (sps->pic_struct_present_flag) {
63         unsigned int i, num_clock_ts;
64
65         h->sei_pic_struct = get_bits(&h->gb, 4);
66         h->sei_ct_type    = 0;
67
68         if (h->sei_pic_struct > SEI_PIC_STRUCT_FRAME_TRIPLING)
69             return AVERROR_INVALIDDATA;
70
71         num_clock_ts = sei_num_clock_ts_table[h->sei_pic_struct];
72
73         for (i = 0; i < num_clock_ts; i++) {
74             if (get_bits(&h->gb, 1)) {                /* clock_timestamp_flag */
75                 unsigned int full_timestamp_flag;
76
77                 h->sei_ct_type |= 1 << get_bits(&h->gb, 2);
78                 skip_bits(&h->gb, 1);                 /* nuit_field_based_flag */
79                 skip_bits(&h->gb, 5);                 /* counting_type */
80                 full_timestamp_flag = get_bits(&h->gb, 1);
81                 skip_bits(&h->gb, 1);                 /* discontinuity_flag */
82                 skip_bits(&h->gb, 1);                 /* cnt_dropped_flag */
83                 skip_bits(&h->gb, 8);                 /* n_frames */
84                 if (full_timestamp_flag) {
85                     skip_bits(&h->gb, 6);             /* seconds_value 0..59 */
86                     skip_bits(&h->gb, 6);             /* minutes_value 0..59 */
87                     skip_bits(&h->gb, 5);             /* hours_value 0..23 */
88                 } else {
89                     if (get_bits(&h->gb, 1)) {        /* seconds_flag */
90                         skip_bits(&h->gb, 6);         /* seconds_value range 0..59 */
91                         if (get_bits(&h->gb, 1)) {    /* minutes_flag */
92                             skip_bits(&h->gb, 6);     /* minutes_value 0..59 */
93                             if (get_bits(&h->gb, 1))  /* hours_flag */
94                                 skip_bits(&h->gb, 5); /* hours_value 0..23 */
95                         }
96                     }
97                 }
98                 if (sps->time_offset_length > 0)
99                     skip_bits(&h->gb,
100                               sps->time_offset_length); /* time_offset */
101             }
102         }
103
104         if (h->avctx->debug & FF_DEBUG_PICT_INFO)
105             av_log(h->avctx, AV_LOG_DEBUG, "ct_type:%X pic_struct:%d\n",
106                    h->sei_ct_type, h->sei_pic_struct);
107     }
108     return 0;
109 }
110
111 static int decode_user_data_itu_t_t35(H264Context *h, int size)
112 {
113     uint32_t user_identifier;
114     int dtg_active_format;
115
116     if (size < 7)
117         return -1;
118     size -= 7;
119
120     skip_bits(&h->gb, 8);   // country_code
121     skip_bits(&h->gb, 16);  // provider_code
122     user_identifier = get_bits_long(&h->gb, 32);
123
124     switch (user_identifier) {
125         case 0x44544731:    // "DTG1" - AFD_data
126             if (size < 1)
127                 return -1;
128             skip_bits(&h->gb, 1);
129             if (get_bits(&h->gb, 1)) {
130                 skip_bits(&h->gb, 6);
131                 if (size < 2)
132                     return -1;
133                 skip_bits(&h->gb, 4);
134                 dtg_active_format = get_bits(&h->gb, 4);
135                 h->avctx->dtg_active_format = dtg_active_format;
136             } else {
137                 skip_bits(&h->gb, 6);
138             }
139             break;
140         default:
141             skip_bits(&h->gb, size * 8);
142             break;
143     }
144
145     return 0;
146 }
147
148 static int decode_unregistered_user_data(H264Context *h, int size)
149 {
150     uint8_t user_data[16 + 256];
151     int e, build, i;
152
153     if (size < 16)
154         return AVERROR_INVALIDDATA;
155
156     for (i = 0; i < sizeof(user_data) - 1 && i < size; i++)
157         user_data[i] = get_bits(&h->gb, 8);
158
159     user_data[i] = 0;
160     e = sscanf(user_data + 16, "x264 - core %d", &build);
161     if (e == 1 && build > 0)
162         h->x264_build = build;
163     if (e == 1 && build == 1 && !strncmp(user_data+16, "x264 - core 0000", 16))
164         h->x264_build = 67;
165
166     if (h->avctx->debug & FF_DEBUG_BUGS)
167         av_log(h->avctx, AV_LOG_DEBUG, "user data:\"%s\"\n", user_data + 16);
168
169     for (; i < size; i++)
170         skip_bits(&h->gb, 8);
171
172     return 0;
173 }
174
175 static int decode_recovery_point(H264Context *h)
176 {
177     h->sei_recovery_frame_cnt = get_ue_golomb(&h->gb);
178
179     /* 1b exact_match_flag,
180      * 1b broken_link_flag,
181      * 2b changing_slice_group_idc */
182     skip_bits(&h->gb, 4);
183
184     if (h->avctx->debug & FF_DEBUG_PICT_INFO)
185         av_log(h->avctx, AV_LOG_DEBUG, "sei_recovery_frame_cnt: %d\n", h->sei_recovery_frame_cnt);
186
187     h->has_recovery_point = 1;
188
189     return 0;
190 }
191
192 static int decode_buffering_period(H264Context *h)
193 {
194     unsigned int sps_id;
195     int sched_sel_idx;
196     SPS *sps;
197
198     sps_id = get_ue_golomb_31(&h->gb);
199     if (sps_id > 31 || !h->sps_buffers[sps_id]) {
200         av_log(h->avctx, AV_LOG_ERROR,
201                "non-existing SPS %d referenced in buffering period\n", sps_id);
202         return AVERROR_INVALIDDATA;
203     }
204     sps = h->sps_buffers[sps_id];
205
206     // NOTE: This is really so duplicated in the standard... See H.264, D.1.1
207     if (sps->nal_hrd_parameters_present_flag) {
208         for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
209             h->initial_cpb_removal_delay[sched_sel_idx] =
210                 get_bits_long(&h->gb, sps->initial_cpb_removal_delay_length);
211             // initial_cpb_removal_delay_offset
212             skip_bits(&h->gb, sps->initial_cpb_removal_delay_length);
213         }
214     }
215     if (sps->vcl_hrd_parameters_present_flag) {
216         for (sched_sel_idx = 0; sched_sel_idx < sps->cpb_cnt; sched_sel_idx++) {
217             h->initial_cpb_removal_delay[sched_sel_idx] =
218                 get_bits_long(&h->gb, sps->initial_cpb_removal_delay_length);
219             // initial_cpb_removal_delay_offset
220             skip_bits(&h->gb, sps->initial_cpb_removal_delay_length);
221         }
222     }
223
224     h->sei_buffering_period_present = 1;
225     return 0;
226 }
227
228 static int decode_frame_packing_arrangement(H264Context *h)
229 {
230     h->sei_fpa.frame_packing_arrangement_id          = get_ue_golomb(&h->gb);
231     h->sei_fpa.frame_packing_arrangement_cancel_flag = get_bits1(&h->gb);
232     h->sei_frame_packing_present = !h->sei_fpa.frame_packing_arrangement_cancel_flag;
233
234     if (h->sei_frame_packing_present) {
235         h->sei_fpa.frame_packing_arrangement_type =
236         h->frame_packing_arrangement_type = get_bits(&h->gb, 7);
237         h->sei_fpa.quincunx_sampling_flag         =
238         h->quincunx_subsampling           = get_bits1(&h->gb);
239         h->sei_fpa.content_interpretation_type    =
240         h->content_interpretation_type    = get_bits(&h->gb, 6);
241
242         // the following skips: spatial_flipping_flag, frame0_flipped_flag,
243         // field_views_flag, current_frame_is_frame0_flag,
244         // frame0_self_contained_flag, frame1_self_contained_flag
245         skip_bits(&h->gb, 6);
246
247         if (!h->quincunx_subsampling && h->frame_packing_arrangement_type != 5)
248             skip_bits(&h->gb, 16);      // frame[01]_grid_position_[xy]
249         skip_bits(&h->gb, 8);           // frame_packing_arrangement_reserved_byte
250         h->sei_fpa.frame_packing_arrangement_repetition_period = get_ue_golomb(&h->gb) /* frame_packing_arrangement_repetition_period */;
251     }
252     skip_bits1(&h->gb);                 // frame_packing_arrangement_extension_flag
253
254     if (h->avctx->debug & FF_DEBUG_PICT_INFO)
255         av_log(h->avctx, AV_LOG_DEBUG, "SEI FPA %d %d %d %d %d %d\n",
256                                        h->sei_fpa.frame_packing_arrangement_id,
257                                        h->sei_fpa.frame_packing_arrangement_cancel_flag,
258                                        h->sei_fpa.frame_packing_arrangement_type,
259                                        h->sei_fpa.quincunx_sampling_flag,
260                                        h->sei_fpa.content_interpretation_type,
261                                        h->sei_fpa.frame_packing_arrangement_repetition_period);
262
263     return 0;
264 }
265
266 static int decode_display_orientation(H264Context *h)
267 {
268     h->sei_display_orientation_present = !get_bits1(&h->gb);
269
270     if (h->sei_display_orientation_present) {
271         h->sei_hflip = get_bits1(&h->gb);     // hor_flip
272         h->sei_vflip = get_bits1(&h->gb);     // ver_flip
273
274         h->sei_anticlockwise_rotation = get_bits(&h->gb, 16);
275         get_ue_golomb(&h->gb);  // display_orientation_repetition_period
276         skip_bits1(&h->gb);     // display_orientation_extension_flag
277     }
278
279     return 0;
280 }
281
282 int ff_h264_decode_sei(H264Context *h)
283 {
284     while (get_bits_left(&h->gb) > 16 && show_bits(&h->gb, 16)) {
285         int type = 0;
286         unsigned size = 0;
287         unsigned next;
288         int ret  = 0;
289
290         do {
291             if (get_bits_left(&h->gb) < 8)
292                 return AVERROR_INVALIDDATA;
293             type += show_bits(&h->gb, 8);
294         } while (get_bits(&h->gb, 8) == 255);
295
296         do {
297             if (get_bits_left(&h->gb) < 8)
298                 return AVERROR_INVALIDDATA;
299             size += show_bits(&h->gb, 8);
300         } while (get_bits(&h->gb, 8) == 255);
301
302         if (h->avctx->debug&FF_DEBUG_STARTCODE)
303             av_log(h->avctx, AV_LOG_DEBUG, "SEI %d len:%d\n", type, size);
304
305         if (size > get_bits_left(&h->gb) / 8) {
306             av_log(h->avctx, AV_LOG_ERROR, "SEI type %d size %d truncated at %d\n",
307                    type, 8*size, get_bits_left(&h->gb));
308             return AVERROR_INVALIDDATA;
309         }
310         next = get_bits_count(&h->gb) + 8 * size;
311
312         switch (type) {
313         case SEI_TYPE_PIC_TIMING: // Picture timing SEI
314             ret = decode_picture_timing(h);
315             if (ret < 0)
316                 return ret;
317             break;
318         case SEI_TYPE_USER_DATA_ITU_T_T35:
319             if (decode_user_data_itu_t_t35(h, size) < 0)
320                 return -1;
321             break;
322         case SEI_TYPE_USER_DATA_UNREGISTERED:
323             ret = decode_unregistered_user_data(h, size);
324             if (ret < 0)
325                 return ret;
326             break;
327         case SEI_TYPE_RECOVERY_POINT:
328             ret = decode_recovery_point(h);
329             if (ret < 0)
330                 return ret;
331             break;
332         case SEI_TYPE_BUFFERING_PERIOD:
333             ret = decode_buffering_period(h);
334             if (ret < 0)
335                 return ret;
336             break;
337         case SEI_TYPE_FRAME_PACKING:
338             ret = decode_frame_packing_arrangement(h);
339             if (ret < 0)
340                 return ret;
341             break;
342         case SEI_TYPE_DISPLAY_ORIENTATION:
343             ret = decode_display_orientation(h);
344             if (ret < 0)
345                 return ret;
346             break;
347         default:
348             av_log(h->avctx, AV_LOG_DEBUG, "unknown SEI type %d\n", type);
349         }
350         skip_bits_long(&h->gb, next - get_bits_count(&h->gb));
351
352         // FIXME check bits here
353         align_get_bits(&h->gb);
354     }
355
356     return 0;
357 }
358
359 const char* ff_h264_sei_stereo_mode(H264Context *h)
360 {
361     if (h->sei_fpa.frame_packing_arrangement_cancel_flag == 0) {
362         switch (h->sei_fpa.frame_packing_arrangement_type) {
363             case SEI_FPA_TYPE_CHECKERBOARD:
364                 if (h->sei_fpa.content_interpretation_type == 2)
365                     return "checkerboard_rl";
366                 else
367                     return "checkerboard_lr";
368             case SEI_FPA_TYPE_INTERLEAVE_COLUMN:
369                 if (h->sei_fpa.content_interpretation_type == 2)
370                     return "col_interleaved_rl";
371                 else
372                     return "col_interleaved_lr";
373             case SEI_FPA_TYPE_INTERLEAVE_ROW:
374                 if (h->sei_fpa.content_interpretation_type == 2)
375                     return "row_interleaved_rl";
376                 else
377                     return "row_interleaved_lr";
378             case SEI_FPA_TYPE_SIDE_BY_SIDE:
379                 if (h->sei_fpa.content_interpretation_type == 2)
380                     return "right_left";
381                 else
382                     return "left_right";
383             case SEI_FPA_TYPE_TOP_BOTTOM:
384                 if (h->sei_fpa.content_interpretation_type == 2)
385                     return "bottom_top";
386                 else
387                     return "top_bottom";
388             case SEI_FPA_TYPE_INTERLEAVE_TEMPORAL:
389                 if (h->sei_fpa.content_interpretation_type == 2)
390                     return "block_rl";
391                 else
392                     return "block_lr";
393             case SEI_FPA_TYPE_2D:
394             default:
395                 return "mono";
396         }
397     } else if (h->sei_fpa.frame_packing_arrangement_cancel_flag == 1) {
398         return "mono";
399     } else {
400         return NULL;
401     }
402 }