ff6c077ed38a5bc43888e0f5aa55965211551436
[ffmpeg.git] / libavcodec / h264_ps.c
1 /*
2  * H.26L/H.264/AVC/JVT/14496-10/... parameter set 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
22 /**
23  * @file
24  * H.264 / AVC / MPEG4 part10 parameter set decoding.
25  * @author Michael Niedermayer <michaelni@gmx.at>
26  */
27
28 #include "libavutil/imgutils.h"
29 #include "internal.h"
30 #include "dsputil.h"
31 #include "avcodec.h"
32 #include "h264.h"
33 #include "h264data.h" //FIXME FIXME FIXME (just for zigzag_scan)
34 #include "golomb.h"
35
36
37 //#undef NDEBUG
38 #include <assert.h>
39
40 #define MAX_LOG2_MAX_FRAME_NUM    (12 + 4)
41 #define MIN_LOG2_MAX_FRAME_NUM    4
42
43 static const AVRational pixel_aspect[17]={
44  {0, 1},
45  {1, 1},
46  {12, 11},
47  {10, 11},
48  {16, 11},
49  {40, 33},
50  {24, 11},
51  {20, 11},
52  {32, 11},
53  {80, 33},
54  {18, 11},
55  {15, 11},
56  {64, 33},
57  {160,99},
58  {4, 3},
59  {3, 2},
60  {2, 1},
61 };
62
63 #define QP(qP,depth) ( (qP)+6*((depth)-8) )
64
65 #define CHROMA_QP_TABLE_END(d) \
66      QP(0,d),  QP(1,d),  QP(2,d),  QP(3,d),  QP(4,d),  QP(5,d),\
67      QP(6,d),  QP(7,d),  QP(8,d),  QP(9,d), QP(10,d), QP(11,d),\
68     QP(12,d), QP(13,d), QP(14,d), QP(15,d), QP(16,d), QP(17,d),\
69     QP(18,d), QP(19,d), QP(20,d), QP(21,d), QP(22,d), QP(23,d),\
70     QP(24,d), QP(25,d), QP(26,d), QP(27,d), QP(28,d), QP(29,d),\
71     QP(29,d), QP(30,d), QP(31,d), QP(32,d), QP(32,d), QP(33,d),\
72     QP(34,d), QP(34,d), QP(35,d), QP(35,d), QP(36,d), QP(36,d),\
73     QP(37,d), QP(37,d), QP(37,d), QP(38,d), QP(38,d), QP(38,d),\
74     QP(39,d), QP(39,d), QP(39,d), QP(39,d)
75
76 const uint8_t ff_h264_chroma_qp[3][QP_MAX_NUM+1] = {
77     {
78         CHROMA_QP_TABLE_END(8)
79     },
80     {
81         0, 1, 2, 3, 4, 5,
82         CHROMA_QP_TABLE_END(9)
83     },
84     {
85         0, 1, 2, 3,  4,  5,
86         6, 7, 8, 9, 10, 11,
87         CHROMA_QP_TABLE_END(10)
88     },
89 };
90
91 static const uint8_t default_scaling4[2][16]={
92 {   6,13,20,28,
93    13,20,28,32,
94    20,28,32,37,
95    28,32,37,42
96 },{
97    10,14,20,24,
98    14,20,24,27,
99    20,24,27,30,
100    24,27,30,34
101 }};
102
103 static const uint8_t default_scaling8[2][64]={
104 {   6,10,13,16,18,23,25,27,
105    10,11,16,18,23,25,27,29,
106    13,16,18,23,25,27,29,31,
107    16,18,23,25,27,29,31,33,
108    18,23,25,27,29,31,33,36,
109    23,25,27,29,31,33,36,38,
110    25,27,29,31,33,36,38,40,
111    27,29,31,33,36,38,40,42
112 },{
113     9,13,15,17,19,21,22,24,
114    13,13,17,19,21,22,24,25,
115    15,17,19,21,22,24,25,27,
116    17,19,21,22,24,25,27,28,
117    19,21,22,24,25,27,28,30,
118    21,22,24,25,27,28,30,32,
119    22,24,25,27,28,30,32,33,
120    24,25,27,28,30,32,33,35
121 }};
122
123 static inline int decode_hrd_parameters(H264Context *h, SPS *sps){
124     MpegEncContext * const s = &h->s;
125     int cpb_count, i;
126     cpb_count = get_ue_golomb_31(&s->gb) + 1;
127
128     if(cpb_count > 32U){
129         av_log(h->s.avctx, AV_LOG_ERROR, "cpb_count %d invalid\n", cpb_count);
130         return -1;
131     }
132
133     get_bits(&s->gb, 4); /* bit_rate_scale */
134     get_bits(&s->gb, 4); /* cpb_size_scale */
135     for(i=0; i<cpb_count; i++){
136         get_ue_golomb_long(&s->gb); /* bit_rate_value_minus1 */
137         get_ue_golomb_long(&s->gb); /* cpb_size_value_minus1 */
138         get_bits1(&s->gb);     /* cbr_flag */
139     }
140     sps->initial_cpb_removal_delay_length = get_bits(&s->gb, 5) + 1;
141     sps->cpb_removal_delay_length = get_bits(&s->gb, 5) + 1;
142     sps->dpb_output_delay_length = get_bits(&s->gb, 5) + 1;
143     sps->time_offset_length = get_bits(&s->gb, 5);
144     sps->cpb_cnt = cpb_count;
145     return 0;
146 }
147
148 static inline int decode_vui_parameters(H264Context *h, SPS *sps){
149     MpegEncContext * const s = &h->s;
150     int aspect_ratio_info_present_flag;
151     unsigned int aspect_ratio_idc;
152
153     aspect_ratio_info_present_flag= get_bits1(&s->gb);
154
155     if( aspect_ratio_info_present_flag ) {
156         aspect_ratio_idc= get_bits(&s->gb, 8);
157         if( aspect_ratio_idc == EXTENDED_SAR ) {
158             sps->sar.num= get_bits(&s->gb, 16);
159             sps->sar.den= get_bits(&s->gb, 16);
160         }else if(aspect_ratio_idc < FF_ARRAY_ELEMS(pixel_aspect)){
161             sps->sar=  pixel_aspect[aspect_ratio_idc];
162         }else{
163             av_log(h->s.avctx, AV_LOG_ERROR, "illegal aspect ratio\n");
164             return -1;
165         }
166     }else{
167         sps->sar.num=
168         sps->sar.den= 0;
169     }
170 //            s->avctx->aspect_ratio= sar_width*s->width / (float)(s->height*sar_height);
171
172     if(get_bits1(&s->gb)){      /* overscan_info_present_flag */
173         get_bits1(&s->gb);      /* overscan_appropriate_flag */
174     }
175
176     sps->video_signal_type_present_flag = get_bits1(&s->gb);
177     if(sps->video_signal_type_present_flag){
178         get_bits(&s->gb, 3);    /* video_format */
179         sps->full_range = get_bits1(&s->gb); /* video_full_range_flag */
180
181         sps->colour_description_present_flag = get_bits1(&s->gb);
182         if(sps->colour_description_present_flag){
183             sps->color_primaries = get_bits(&s->gb, 8); /* colour_primaries */
184             sps->color_trc       = get_bits(&s->gb, 8); /* transfer_characteristics */
185             sps->colorspace      = get_bits(&s->gb, 8); /* matrix_coefficients */
186             if (sps->color_primaries >= AVCOL_PRI_NB)
187                 sps->color_primaries  = AVCOL_PRI_UNSPECIFIED;
188             if (sps->color_trc >= AVCOL_TRC_NB)
189                 sps->color_trc  = AVCOL_TRC_UNSPECIFIED;
190             if (sps->colorspace >= AVCOL_SPC_NB)
191                 sps->colorspace  = AVCOL_SPC_UNSPECIFIED;
192         }
193     }
194
195     if(get_bits1(&s->gb)){      /* chroma_location_info_present_flag */
196         s->avctx->chroma_sample_location = get_ue_golomb(&s->gb)+1;  /* chroma_sample_location_type_top_field */
197         get_ue_golomb(&s->gb);  /* chroma_sample_location_type_bottom_field */
198     }
199
200     sps->timing_info_present_flag = get_bits1(&s->gb);
201     if(sps->timing_info_present_flag){
202         sps->num_units_in_tick = get_bits_long(&s->gb, 32);
203         sps->time_scale = get_bits_long(&s->gb, 32);
204         if(!sps->num_units_in_tick || !sps->time_scale){
205             av_log(h->s.avctx, AV_LOG_ERROR, "time_scale/num_units_in_tick invalid or unsupported (%d/%d)\n", sps->time_scale, sps->num_units_in_tick);
206             return -1;
207         }
208         sps->fixed_frame_rate_flag = get_bits1(&s->gb);
209     }
210
211     sps->nal_hrd_parameters_present_flag = get_bits1(&s->gb);
212     if(sps->nal_hrd_parameters_present_flag)
213         if(decode_hrd_parameters(h, sps) < 0)
214             return -1;
215     sps->vcl_hrd_parameters_present_flag = get_bits1(&s->gb);
216     if(sps->vcl_hrd_parameters_present_flag)
217         if(decode_hrd_parameters(h, sps) < 0)
218             return -1;
219     if(sps->nal_hrd_parameters_present_flag || sps->vcl_hrd_parameters_present_flag)
220         get_bits1(&s->gb);     /* low_delay_hrd_flag */
221     sps->pic_struct_present_flag = get_bits1(&s->gb);
222
223     sps->bitstream_restriction_flag = get_bits1(&s->gb);
224     if(sps->bitstream_restriction_flag){
225         get_bits1(&s->gb);     /* motion_vectors_over_pic_boundaries_flag */
226         get_ue_golomb(&s->gb); /* max_bytes_per_pic_denom */
227         get_ue_golomb(&s->gb); /* max_bits_per_mb_denom */
228         get_ue_golomb(&s->gb); /* log2_max_mv_length_horizontal */
229         get_ue_golomb(&s->gb); /* log2_max_mv_length_vertical */
230         sps->num_reorder_frames= get_ue_golomb(&s->gb);
231         get_ue_golomb(&s->gb); /*max_dec_frame_buffering*/
232
233         if (get_bits_left(&s->gb) < 0) {
234             sps->num_reorder_frames=0;
235             sps->bitstream_restriction_flag= 0;
236         }
237
238         if(sps->num_reorder_frames > 16U /*max_dec_frame_buffering || max_dec_frame_buffering > 16*/){
239             av_log(h->s.avctx, AV_LOG_ERROR, "illegal num_reorder_frames %d\n", sps->num_reorder_frames);
240             return -1;
241         }
242     }
243     if (get_bits_left(&s->gb) < 0) {
244         av_log(h->s.avctx, AV_LOG_ERROR, "Overread VUI by %d bits\n", -get_bits_left(&s->gb));
245         return AVERROR_INVALIDDATA;
246     }
247
248     return 0;
249 }
250
251 static void decode_scaling_list(H264Context *h, uint8_t *factors, int size,
252                                 const uint8_t *jvt_list, const uint8_t *fallback_list){
253     MpegEncContext * const s = &h->s;
254     int i, last = 8, next = 8;
255     const uint8_t *scan = size == 16 ? zigzag_scan : ff_zigzag_direct;
256     if(!get_bits1(&s->gb)) /* matrix not written, we use the predicted one */
257         memcpy(factors, fallback_list, size*sizeof(uint8_t));
258     else
259     for(i=0;i<size;i++){
260         if(next)
261             next = (last + get_se_golomb(&s->gb)) & 0xff;
262         if(!i && !next){ /* matrix not written, we use the preset one */
263             memcpy(factors, jvt_list, size*sizeof(uint8_t));
264             break;
265         }
266         last = factors[scan[i]] = next ? next : last;
267     }
268 }
269
270 static void decode_scaling_matrices(H264Context *h, SPS *sps, PPS *pps, int is_sps,
271                                    uint8_t (*scaling_matrix4)[16], uint8_t (*scaling_matrix8)[64]){
272     MpegEncContext * const s = &h->s;
273     int fallback_sps = !is_sps && sps->scaling_matrix_present;
274     const uint8_t *fallback[4] = {
275         fallback_sps ? sps->scaling_matrix4[0] : default_scaling4[0],
276         fallback_sps ? sps->scaling_matrix4[3] : default_scaling4[1],
277         fallback_sps ? sps->scaling_matrix8[0] : default_scaling8[0],
278         fallback_sps ? sps->scaling_matrix8[3] : default_scaling8[1]
279     };
280     if(get_bits1(&s->gb)){
281         sps->scaling_matrix_present |= is_sps;
282         decode_scaling_list(h,scaling_matrix4[0],16,default_scaling4[0],fallback[0]); // Intra, Y
283         decode_scaling_list(h,scaling_matrix4[1],16,default_scaling4[0],scaling_matrix4[0]); // Intra, Cr
284         decode_scaling_list(h,scaling_matrix4[2],16,default_scaling4[0],scaling_matrix4[1]); // Intra, Cb
285         decode_scaling_list(h,scaling_matrix4[3],16,default_scaling4[1],fallback[1]); // Inter, Y
286         decode_scaling_list(h,scaling_matrix4[4],16,default_scaling4[1],scaling_matrix4[3]); // Inter, Cr
287         decode_scaling_list(h,scaling_matrix4[5],16,default_scaling4[1],scaling_matrix4[4]); // Inter, Cb
288         if(is_sps || pps->transform_8x8_mode){
289             decode_scaling_list(h,scaling_matrix8[0],64,default_scaling8[0],fallback[2]);  // Intra, Y
290             if(sps->chroma_format_idc == 3){
291                 decode_scaling_list(h,scaling_matrix8[1],64,default_scaling8[0],scaling_matrix8[0]);  // Intra, Cr
292                 decode_scaling_list(h,scaling_matrix8[2],64,default_scaling8[0],scaling_matrix8[1]);  // Intra, Cb
293             }
294             decode_scaling_list(h,scaling_matrix8[3],64,default_scaling8[1],fallback[3]);  // Inter, Y
295             if(sps->chroma_format_idc == 3){
296                 decode_scaling_list(h,scaling_matrix8[4],64,default_scaling8[1],scaling_matrix8[3]);  // Inter, Cr
297                 decode_scaling_list(h,scaling_matrix8[5],64,default_scaling8[1],scaling_matrix8[4]);  // Inter, Cb
298             }
299         }
300     }
301 }
302
303 int ff_h264_decode_seq_parameter_set(H264Context *h){
304     MpegEncContext * const s = &h->s;
305     int profile_idc, level_idc, constraint_set_flags = 0;
306     unsigned int sps_id;
307     int i, log2_max_frame_num_minus4;
308     SPS *sps;
309
310     profile_idc= get_bits(&s->gb, 8);
311     constraint_set_flags |= get_bits1(&s->gb) << 0;   //constraint_set0_flag
312     constraint_set_flags |= get_bits1(&s->gb) << 1;   //constraint_set1_flag
313     constraint_set_flags |= get_bits1(&s->gb) << 2;   //constraint_set2_flag
314     constraint_set_flags |= get_bits1(&s->gb) << 3;   //constraint_set3_flag
315     get_bits(&s->gb, 4); // reserved
316     level_idc= get_bits(&s->gb, 8);
317     sps_id= get_ue_golomb_31(&s->gb);
318
319     if(sps_id >= MAX_SPS_COUNT) {
320         av_log(h->s.avctx, AV_LOG_ERROR, "sps_id (%d) out of range\n", sps_id);
321         return -1;
322     }
323     sps= av_mallocz(sizeof(SPS));
324     if(sps == NULL)
325         return -1;
326
327     sps->time_offset_length = 24;
328     sps->profile_idc= profile_idc;
329     sps->constraint_set_flags = constraint_set_flags;
330     sps->level_idc= level_idc;
331
332     memset(sps->scaling_matrix4, 16, sizeof(sps->scaling_matrix4));
333     memset(sps->scaling_matrix8, 16, sizeof(sps->scaling_matrix8));
334     sps->scaling_matrix_present = 0;
335
336     if (sps->profile_idc == 100 || sps->profile_idc == 110 ||
337         sps->profile_idc == 122 || sps->profile_idc == 244 ||
338         sps->profile_idc ==  44 || sps->profile_idc ==  83 ||
339         sps->profile_idc ==  86 || sps->profile_idc == 118 ||
340         sps->profile_idc == 128 || sps->profile_idc == 144) {
341         sps->chroma_format_idc= get_ue_golomb_31(&s->gb);
342         if(sps->chroma_format_idc > 3) {
343             av_log(h->s.avctx, AV_LOG_ERROR, "chroma_format_idc (%u) out of range\n", sps->chroma_format_idc);
344             goto fail;
345         } else if(sps->chroma_format_idc == 3) {
346             sps->residual_color_transform_flag = get_bits1(&s->gb);
347         }
348         sps->bit_depth_luma   = get_ue_golomb(&s->gb) + 8;
349         sps->bit_depth_chroma = get_ue_golomb(&s->gb) + 8;
350         sps->transform_bypass = get_bits1(&s->gb);
351         decode_scaling_matrices(h, sps, NULL, 1, sps->scaling_matrix4, sps->scaling_matrix8);
352     }else{
353         sps->chroma_format_idc= 1;
354         sps->bit_depth_luma   = 8;
355         sps->bit_depth_chroma = 8;
356     }
357
358     log2_max_frame_num_minus4 = get_ue_golomb(&s->gb);
359     if (log2_max_frame_num_minus4 < MIN_LOG2_MAX_FRAME_NUM - 4 ||
360         log2_max_frame_num_minus4 > MAX_LOG2_MAX_FRAME_NUM - 4) {
361         av_log(h->s.avctx, AV_LOG_ERROR,
362                "log2_max_frame_num_minus4 out of range (0-12): %d\n",
363                log2_max_frame_num_minus4);
364         goto fail;
365     }
366     sps->log2_max_frame_num = log2_max_frame_num_minus4 + 4;
367
368     sps->poc_type= get_ue_golomb_31(&s->gb);
369
370     if(sps->poc_type == 0){ //FIXME #define
371         sps->log2_max_poc_lsb= get_ue_golomb(&s->gb) + 4;
372     } else if(sps->poc_type == 1){//FIXME #define
373         sps->delta_pic_order_always_zero_flag= get_bits1(&s->gb);
374         sps->offset_for_non_ref_pic= get_se_golomb(&s->gb);
375         sps->offset_for_top_to_bottom_field= get_se_golomb(&s->gb);
376         sps->poc_cycle_length                = get_ue_golomb(&s->gb);
377
378         if((unsigned)sps->poc_cycle_length >= FF_ARRAY_ELEMS(sps->offset_for_ref_frame)){
379             av_log(h->s.avctx, AV_LOG_ERROR, "poc_cycle_length overflow %u\n", sps->poc_cycle_length);
380             goto fail;
381         }
382
383         for(i=0; i<sps->poc_cycle_length; i++)
384             sps->offset_for_ref_frame[i]= get_se_golomb(&s->gb);
385     }else if(sps->poc_type != 2){
386         av_log(h->s.avctx, AV_LOG_ERROR, "illegal POC type %d\n", sps->poc_type);
387         goto fail;
388     }
389
390     sps->ref_frame_count= get_ue_golomb_31(&s->gb);
391     if(sps->ref_frame_count > MAX_PICTURE_COUNT-2 || sps->ref_frame_count >= 32U){
392         av_log(h->s.avctx, AV_LOG_ERROR, "too many reference frames\n");
393         goto fail;
394     }
395     sps->gaps_in_frame_num_allowed_flag= get_bits1(&s->gb);
396     sps->mb_width = get_ue_golomb(&s->gb) + 1;
397     sps->mb_height= get_ue_golomb(&s->gb) + 1;
398     if((unsigned)sps->mb_width >= INT_MAX/16 || (unsigned)sps->mb_height >= INT_MAX/16 ||
399        av_image_check_size(16*sps->mb_width, 16*sps->mb_height, 0, h->s.avctx)){
400         av_log(h->s.avctx, AV_LOG_ERROR, "mb_width/height overflow\n");
401         goto fail;
402     }
403
404     sps->frame_mbs_only_flag= get_bits1(&s->gb);
405     if(!sps->frame_mbs_only_flag)
406         sps->mb_aff= get_bits1(&s->gb);
407     else
408         sps->mb_aff= 0;
409
410     sps->direct_8x8_inference_flag= get_bits1(&s->gb);
411     if(!sps->frame_mbs_only_flag && !sps->direct_8x8_inference_flag){
412         av_log(h->s.avctx, AV_LOG_ERROR, "This stream was generated by a broken encoder, invalid 8x8 inference\n");
413         goto fail;
414     }
415
416 #ifndef ALLOW_INTERLACE
417     if(sps->mb_aff)
418         av_log(h->s.avctx, AV_LOG_ERROR, "MBAFF support not included; enable it at compile-time.\n");
419 #endif
420     sps->crop= get_bits1(&s->gb);
421     if(sps->crop){
422         int crop_vertical_limit   = sps->chroma_format_idc  & 2 ? 16 : 8;
423         int crop_horizontal_limit = sps->chroma_format_idc == 3 ? 16 : 8;
424         sps->crop_left  = get_ue_golomb(&s->gb);
425         sps->crop_right = get_ue_golomb(&s->gb);
426         sps->crop_top   = get_ue_golomb(&s->gb);
427         sps->crop_bottom= get_ue_golomb(&s->gb);
428         if(sps->crop_left || sps->crop_top){
429             av_log(h->s.avctx, AV_LOG_ERROR, "insane cropping not completely supported, this could look slightly wrong ...\n");
430         }
431         if(sps->crop_right >= crop_horizontal_limit || sps->crop_bottom >= crop_vertical_limit){
432             av_log(h->s.avctx, AV_LOG_ERROR, "brainfart cropping not supported, this could look slightly wrong ...\n");
433         }
434     }else{
435         sps->crop_left  =
436         sps->crop_right =
437         sps->crop_top   =
438         sps->crop_bottom= 0;
439     }
440
441     sps->vui_parameters_present_flag= get_bits1(&s->gb);
442     if( sps->vui_parameters_present_flag )
443         if (decode_vui_parameters(h, sps) < 0)
444             goto fail;
445
446     if(!sps->sar.den)
447         sps->sar.den= 1;
448
449     if(s->avctx->debug&FF_DEBUG_PICT_INFO){
450         static const char csp[4][5] = { "Gray", "420", "422", "444" };
451         av_log(h->s.avctx, AV_LOG_DEBUG, "sps:%u profile:%d/%d poc:%d ref:%d %dx%d %s %s crop:%d/%d/%d/%d %s %s %d/%d\n",
452                sps_id, sps->profile_idc, sps->level_idc,
453                sps->poc_type,
454                sps->ref_frame_count,
455                sps->mb_width, sps->mb_height,
456                sps->frame_mbs_only_flag ? "FRM" : (sps->mb_aff ? "MB-AFF" : "PIC-AFF"),
457                sps->direct_8x8_inference_flag ? "8B8" : "",
458                sps->crop_left, sps->crop_right,
459                sps->crop_top, sps->crop_bottom,
460                sps->vui_parameters_present_flag ? "VUI" : "",
461                csp[sps->chroma_format_idc],
462                sps->timing_info_present_flag ? sps->num_units_in_tick : 0,
463                sps->timing_info_present_flag ? sps->time_scale : 0
464                );
465     }
466     sps->new = 1;
467
468     av_free(h->sps_buffers[sps_id]);
469     h->sps_buffers[sps_id] = sps;
470     h->sps                 = *sps;
471     h->current_sps_id      = sps_id;
472
473     return 0;
474 fail:
475     av_free(sps);
476     return -1;
477 }
478
479 static void
480 build_qp_table(PPS *pps, int t, int index, const int depth)
481 {
482     int i;
483     const int max_qp = 51 + 6*(depth-8);
484     for(i = 0; i < max_qp+1; i++)
485         pps->chroma_qp_table[t][i] = ff_h264_chroma_qp[depth-8][av_clip(i + index, 0, max_qp)];
486 }
487
488 int ff_h264_decode_picture_parameter_set(H264Context *h, int bit_length){
489     MpegEncContext * const s = &h->s;
490     unsigned int pps_id= get_ue_golomb(&s->gb);
491     PPS *pps;
492     const int qp_bd_offset = 6*(h->sps.bit_depth_luma-8);
493     int bits_left;
494
495     if(pps_id >= MAX_PPS_COUNT) {
496         av_log(h->s.avctx, AV_LOG_ERROR, "pps_id (%d) out of range\n", pps_id);
497         return -1;
498     } else if (h->sps.bit_depth_luma > 10) {
499         av_log(h->s.avctx, AV_LOG_ERROR, "Unimplemented luma bit depth=%d (max=10)\n", h->sps.bit_depth_luma);
500         return AVERROR_PATCHWELCOME;
501     }
502
503     pps= av_mallocz(sizeof(PPS));
504     if(pps == NULL)
505         return -1;
506     pps->sps_id= get_ue_golomb_31(&s->gb);
507     if((unsigned)pps->sps_id>=MAX_SPS_COUNT || h->sps_buffers[pps->sps_id] == NULL){
508         av_log(h->s.avctx, AV_LOG_ERROR, "sps_id out of range\n");
509         goto fail;
510     }
511
512     pps->cabac= get_bits1(&s->gb);
513     pps->pic_order_present= get_bits1(&s->gb);
514     pps->slice_group_count= get_ue_golomb(&s->gb) + 1;
515     if(pps->slice_group_count > 1 ){
516         pps->mb_slice_group_map_type= get_ue_golomb(&s->gb);
517         av_log(h->s.avctx, AV_LOG_ERROR, "FMO not supported\n");
518         switch(pps->mb_slice_group_map_type){
519         case 0:
520 #if 0
521 |   for( i = 0; i <= num_slice_groups_minus1; i++ ) |   |        |
522 |    run_length[ i ]                                |1  |ue(v)   |
523 #endif
524             break;
525         case 2:
526 #if 0
527 |   for( i = 0; i < num_slice_groups_minus1; i++ )  |   |        |
528 |{                                                  |   |        |
529 |    top_left_mb[ i ]                               |1  |ue(v)   |
530 |    bottom_right_mb[ i ]                           |1  |ue(v)   |
531 |   }                                               |   |        |
532 #endif
533             break;
534         case 3:
535         case 4:
536         case 5:
537 #if 0
538 |   slice_group_change_direction_flag               |1  |u(1)    |
539 |   slice_group_change_rate_minus1                  |1  |ue(v)   |
540 #endif
541             break;
542         case 6:
543 #if 0
544 |   slice_group_id_cnt_minus1                       |1  |ue(v)   |
545 |   for( i = 0; i <= slice_group_id_cnt_minus1; i++ |   |        |
546 |)                                                  |   |        |
547 |    slice_group_id[ i ]                            |1  |u(v)    |
548 #endif
549             break;
550         }
551     }
552     pps->ref_count[0]= get_ue_golomb(&s->gb) + 1;
553     pps->ref_count[1]= get_ue_golomb(&s->gb) + 1;
554     if(pps->ref_count[0]-1 > 32-1 || pps->ref_count[1]-1 > 32-1){
555         av_log(h->s.avctx, AV_LOG_ERROR, "reference overflow (pps)\n");
556         goto fail;
557     }
558
559     pps->weighted_pred= get_bits1(&s->gb);
560     pps->weighted_bipred_idc= get_bits(&s->gb, 2);
561     pps->init_qp= get_se_golomb(&s->gb) + 26 + qp_bd_offset;
562     pps->init_qs= get_se_golomb(&s->gb) + 26 + qp_bd_offset;
563     pps->chroma_qp_index_offset[0]= get_se_golomb(&s->gb);
564     pps->deblocking_filter_parameters_present= get_bits1(&s->gb);
565     pps->constrained_intra_pred= get_bits1(&s->gb);
566     pps->redundant_pic_cnt_present = get_bits1(&s->gb);
567
568     pps->transform_8x8_mode= 0;
569     h->dequant_coeff_pps= -1; //contents of sps/pps can change even if id doesn't, so reinit
570     memcpy(pps->scaling_matrix4, h->sps_buffers[pps->sps_id]->scaling_matrix4, sizeof(pps->scaling_matrix4));
571     memcpy(pps->scaling_matrix8, h->sps_buffers[pps->sps_id]->scaling_matrix8, sizeof(pps->scaling_matrix8));
572
573     bits_left = bit_length - get_bits_count(&s->gb);
574     if (bits_left && (bits_left > 8 ||
575                       show_bits(&s->gb, bits_left) != 1 << (bits_left - 1))) {
576         pps->transform_8x8_mode= get_bits1(&s->gb);
577         decode_scaling_matrices(h, h->sps_buffers[pps->sps_id], pps, 0, pps->scaling_matrix4, pps->scaling_matrix8);
578         pps->chroma_qp_index_offset[1]= get_se_golomb(&s->gb); //second_chroma_qp_index_offset
579     } else {
580         pps->chroma_qp_index_offset[1]= pps->chroma_qp_index_offset[0];
581     }
582
583     build_qp_table(pps, 0, pps->chroma_qp_index_offset[0], h->sps.bit_depth_luma);
584     build_qp_table(pps, 1, pps->chroma_qp_index_offset[1], h->sps.bit_depth_luma);
585     if(pps->chroma_qp_index_offset[0] != pps->chroma_qp_index_offset[1])
586         pps->chroma_qp_diff= 1;
587
588     if(s->avctx->debug&FF_DEBUG_PICT_INFO){
589         av_log(h->s.avctx, AV_LOG_DEBUG, "pps:%u sps:%u %s slice_groups:%d ref:%d/%d %s qp:%d/%d/%d/%d %s %s %s %s\n",
590                pps_id, pps->sps_id,
591                pps->cabac ? "CABAC" : "CAVLC",
592                pps->slice_group_count,
593                pps->ref_count[0], pps->ref_count[1],
594                pps->weighted_pred ? "weighted" : "",
595                pps->init_qp, pps->init_qs, pps->chroma_qp_index_offset[0], pps->chroma_qp_index_offset[1],
596                pps->deblocking_filter_parameters_present ? "LPAR" : "",
597                pps->constrained_intra_pred ? "CONSTR" : "",
598                pps->redundant_pic_cnt_present ? "REDU" : "",
599                pps->transform_8x8_mode ? "8x8DCT" : ""
600                );
601     }
602
603     av_free(h->pps_buffers[pps_id]);
604     h->pps_buffers[pps_id]= pps;
605     return 0;
606 fail:
607     av_free(pps);
608     return -1;
609 }