git.sesse.net Git - vlc/blob - modules/packetizer/h264.c

   1 /*****************************************************************************
   2  * h264.c: h264/avc video packetizer
   3  *****************************************************************************
   4  * Copyright (C) 2001, 2002, 2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *          Eric Petit <titer@videolan.org>
   9  *          Gildas Bazin <gbazin@videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29 #include <stdlib.h>                                      /* malloc(), free() */
  30
  31 #include <vlc/vlc.h>
  32 #include <vlc/decoder.h>
  33 #include <vlc/sout.h>
  34
  35 #include "vlc_block_helper.h"
  36 #include "vlc_bits.h"
  37
  38 /*****************************************************************************
  39  * Module descriptor
  40  *****************************************************************************/
  41 static int  Open ( vlc_object_t * );
  42 static void Close( vlc_object_t * );
  43
  44 vlc_module_begin();
  45     set_category( CAT_SOUT );
  46     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  47     set_description( _("H.264 video packetizer") );
  48     set_capability( "packetizer", 50 );
  49     set_callbacks( Open, Close );
  50 vlc_module_end();
  51
  52
  53 /****************************************************************************
  54  * Local prototypes
  55  ****************************************************************************/
  56 static block_t *Packetize( decoder_t *, block_t ** );
  57 static block_t *PacketizeAVC1( decoder_t *, block_t ** );
  58
  59 struct decoder_sys_t
  60 {
  61     block_bytestream_t bytestream;
  62
  63     int     i_state;
  64     int     i_offset;
  65     uint8_t startcode[4];
  66
  67     vlc_bool_t b_slice;
  68     block_t    *p_frame;
  69
  70     vlc_bool_t   b_sps;
  71     vlc_bool_t   b_pps;
  72
  73     /* avcC data */
  74     int i_avcC_length_size;
  75     block_t *p_sps;
  76     block_t *p_pps;
  77
  78     /* Useful values of the Sequence Parameter Set */
  79     int i_log2_max_frame_num;
  80     int b_frame_mbs_only;
  81
  82     /* Useful values of the Slice Header */
  83     int i_nal_type;
  84     int i_nal_ref_idc;
  85     int i_idr_pic_id;
  86     int i_frame_num;
  87     int i_frame_type;
  88 };
  89
  90 enum
  91 {
  92     STATE_NOSYNC,
  93     STATE_NEXT_SYNC,
  94 };
  95
  96 enum nal_unit_type_e
  97 {
  98     NAL_UNKNOWN = 0,
  99     NAL_SLICE   = 1,
 100     NAL_SLICE_DPA   = 2,
 101     NAL_SLICE_DPB   = 3,
 102     NAL_SLICE_DPC   = 4,
 103     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 104     NAL_SEI         = 6,    /* ref_idc == 0 */
 105     NAL_SPS         = 7,
 106     NAL_PPS         = 8,
 107     NAL_AU_DELIMITER= 9
 108     /* ref_idc == 0 for 6,9,10,11,12 */
 109 };
 110
 111 enum nal_priority_e
 112 {
 113     NAL_PRIORITY_DISPOSABLE = 0,
 114     NAL_PRIORITY_LOW        = 1,
 115     NAL_PRIORITY_HIGH       = 2,
 116     NAL_PRIORITY_HIGHEST    = 3,
 117 };
 118
 119 static block_t *ParseNALBlock( decoder_t *, block_t * );
 120
 121 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 122
 123 /*****************************************************************************
 124  * Open: probe the packetizer and return score
 125  * When opening after demux, the packetizer is only loaded AFTER the decoder
 126  * That means that what you set in fmt_out is ignored by the decoder in this special case
 127  *****************************************************************************/
 128 static int Open( vlc_object_t *p_this )
 129 {
 130     decoder_t     *p_dec = (decoder_t*)p_this;
 131     decoder_sys_t *p_sys;
 132
 133     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 134         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 135         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 136         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 137         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 138         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 139           p_dec->fmt_in.i_extra < 7 ) )
 140     {
 141         return VLC_EGENERIC;
 142     }
 143
 144     /* Allocate the memory needed to store the decoder's structure */
 145     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 146     {
 147         msg_Err( p_dec, "out of memory" );
 148         return VLC_EGENERIC;
 149     }
 150     p_sys->i_state = STATE_NOSYNC;
 151     p_sys->i_offset = 0;
 152     p_sys->startcode[0] = 0;
 153     p_sys->startcode[1] = 0;
 154     p_sys->startcode[2] = 0;
 155     p_sys->startcode[3] = 1;
 156     p_sys->bytestream = block_BytestreamInit( p_dec );
 157     p_sys->b_slice = VLC_FALSE;
 158     p_sys->p_frame = NULL;
 159     p_sys->b_sps   = VLC_FALSE;
 160     p_sys->b_pps   = VLC_FALSE;
 161     p_sys->p_sps   = 0;
 162     p_sys->p_pps   = 0;
 163
 164     p_sys->i_nal_type = -1;
 165     p_sys->i_nal_ref_idc = -1;
 166     p_sys->i_idr_pic_id = -1;
 167     p_sys->i_frame_num = -1;
 168     p_sys->i_frame_type = 0;
 169
 170     /* Setup properties */
 171     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 172     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 173
 174     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 175     {
 176         /* This type of stream is produced by mp4 and matroska
 177          * when we want to store it in another streamformat, you need to convert
 178          * The fmt_in.p_extra should ALWAYS contain the avcC
 179          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 180         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 181         int i_sps, i_pps;
 182         int i;
 183
 184         /* Parse avcC */
 185         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 186
 187         /* Read SPS */
 188         i_sps = (*p++)&0x1f;
 189         for( i = 0; i < i_sps; i++ )
 190         {
 191             int i_length = GetWBE( p );
 192             block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
 193
 194             p_sys->p_sps = block_Duplicate( p_sps );
 195             p_sps->i_pts = p_sps->i_dts = mdate();
 196             ParseNALBlock( p_dec, p_sps );
 197             p += 2 + i_length;
 198         }
 199         /* Read PPS */
 200         i_pps = *p++;
 201         for( i = 0; i < i_pps; i++ )
 202         {
 203             int i_length = GetWBE( p );
 204             block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
 205
 206             p_sys->p_pps = block_Duplicate( p_pps );
 207             p_pps->i_pts = p_pps->i_dts = mdate();
 208             ParseNALBlock( p_dec, p_pps );
 209             p += 2 + i_length;
 210         }
 211         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 212                  p_sys->i_avcC_length_size, i_sps, i_pps );
 213
 214         /* FIXME: FFMPEG isn't happy at all if you leave this */
 215         if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 216         p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = NULL;
 217
 218         /* Set the new extradata */
 219         p_dec->fmt_out.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 220         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 221         memcpy( p_dec->fmt_out.p_extra, p_sys->p_sps->p_buffer, p_sys->p_sps->i_buffer);
 222         memcpy( p_dec->fmt_out.p_extra+p_sys->p_sps->i_buffer, p_sys->p_pps->p_buffer, p_sys->p_pps->i_buffer);
 223
 224         /* Set callback */
 225         p_dec->pf_packetize = PacketizeAVC1;
 226     }
 227     else
 228     {
 229         /* This type of stream contains data with 3 of 4 byte startcodes
 230          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 231          * The fmt_out.p_extra should be the same */
 232
 233         /* Set callback */
 234         p_dec->pf_packetize = Packetize;
 235
 236         /* */
 237         if( p_dec->fmt_in.i_extra > 0 )
 238         {
 239             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 240             block_t *p_pic;
 241
 242             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 243                     p_dec->fmt_in.i_extra );
 244
 245             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 246             {
 247                 /* Should not occur because we should only receive SPS/PPS */
 248                 block_Release( p_pic );
 249             }
 250         }
 251     }
 252
 253     return VLC_SUCCESS;
 254 }
 255
 256 /*****************************************************************************
 257  * Close: clean up the packetizer
 258  *****************************************************************************/
 259 static void Close( vlc_object_t *p_this )
 260 {
 261     decoder_t *p_dec = (decoder_t*)p_this;
 262     decoder_sys_t *p_sys = p_dec->p_sys;
 263
 264     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 265     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 266     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 267     block_BytestreamRelease( &p_sys->bytestream );
 268     free( p_sys );
 269 }
 270
 271 /****************************************************************************
 272  * Packetize: the whole thing
 273  * Search for the startcodes 3 or more bytes
 274  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 275  ****************************************************************************/
 276 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 277 {
 278     decoder_sys_t *p_sys = p_dec->p_sys;
 279     block_t       *p_pic;
 280
 281     if( !pp_block || !*pp_block ) return NULL;
 282
 283     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 284
 285     for( ;; )
 286     {
 287         switch( p_sys->i_state )
 288         {
 289             case STATE_NOSYNC:
 290                 /* Skip until 3 byte startcode 0 0 1 */
 291                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 292                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 293                 {
 294                     p_sys->i_state = STATE_NEXT_SYNC;
 295                 }
 296
 297                 if( p_sys->i_offset )
 298                 {
 299                     /* skip the data */
 300                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 301                     p_sys->i_offset = 0;
 302                     block_BytestreamFlush( &p_sys->bytestream );
 303                 }
 304
 305                 if( p_sys->i_state != STATE_NEXT_SYNC )
 306                 {
 307                     /* Need more data */
 308                     return NULL;
 309                 }
 310
 311                 p_sys->i_offset = 1; /* To find next startcode */
 312
 313             case STATE_NEXT_SYNC:
 314                 /* Find the next 3 byte startcode 0 0 1*/
 315                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 316                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 317                 {
 318                     /* Need more data */
 319                     return NULL;
 320                 }
 321
 322                 /* Get the new fragment and set the pts/dts */
 323                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 324                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 325                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 326                 /* Force 4 byte startcode 0 0 0 1 */
 327                 p_pic->p_buffer[0] = 0;
 328
 329                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 330                                 p_pic->i_buffer-1 );
 331
 332                 /* Remove trailing 0 bytes */
 333                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) ) p_pic->i_buffer--;
 334                 p_sys->i_offset = 0;
 335
 336                 /* Parse the NAL */
 337                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 338                 {
 339                     p_sys->i_state = STATE_NOSYNC;
 340                     break;
 341                 }
 342 #if 0
 343                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 344                          p_pic->i_pts, p_pic->i_dts );
 345 #endif
 346
 347                 /* So p_block doesn't get re-added several times */
 348                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 349
 350                 p_sys->i_state = STATE_NOSYNC;
 351
 352                 return p_pic;
 353         }
 354     }
 355 }
 356
 357 /****************************************************************************
 358  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 359  * Will always use 4 byte 0 0 0 1 startcodes
 360  * Will prepend a SPS and PPS before each keyframe
 361  ****************************************************************************/
 362 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 363 {
 364     decoder_sys_t *p_sys = p_dec->p_sys;
 365     block_t       *p_block;
 366     block_t       *p_ret = NULL;
 367     uint8_t       *p;
 368
 369     if( !pp_block || !*pp_block ) return NULL;
 370
 371     p_block = *pp_block;
 372     *pp_block = NULL;
 373
 374     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 375     {
 376         block_t *p_pic;
 377         int i_size = 0;
 378         int i;
 379
 380         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 381         {
 382             i_size = (i_size << 8) | (*p++);
 383         }
 384
 385         if( i_size > 0 )
 386         {
 387             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 388
 389             p_part->i_dts = p_block->i_dts;
 390             p_part->i_pts = p_block->i_pts;
 391
 392             /* Parse the NAL */
 393             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 394             {
 395                 block_ChainAppend( &p_ret, p_pic );
 396             }
 397         }
 398         p += i_size;
 399     }
 400     block_Release( p_block );
 401
 402     return p_ret;
 403 }
 404
 405 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 406 {
 407     block_t *p_nal;
 408
 409     p_nal = block_New( p_dec, 4 + i_size );
 410
 411     /* Add start code */
 412     p_nal->p_buffer[0] = 0x00;
 413     p_nal->p_buffer[1] = 0x00;
 414     p_nal->p_buffer[2] = 0x00;
 415     p_nal->p_buffer[3] = 0x01;
 416
 417     /* Copy nalu */
 418     memcpy( &p_nal->p_buffer[4], p, i_size );
 419
 420     return p_nal;
 421 }
 422
 423 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 424                              uint8_t *src, int i_src )
 425 {
 426     uint8_t *end = &src[i_src];
 427     uint8_t *dst = malloc( i_src );
 428
 429     *pp_ret = dst;
 430
 431     while( src < end )
 432     {
 433         if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 434             src[2] == 0x03 )
 435         {
 436             *dst++ = 0x00;
 437             *dst++ = 0x00;
 438
 439             src += 3;
 440             continue;
 441         }
 442         *dst++ = *src++;
 443     }
 444
 445     *pi_ret = dst - *pp_ret;
 446 }
 447
 448 static inline int bs_read_ue( bs_t *s )
 449 {
 450     int i = 0;
 451
 452     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 453     {
 454         i++;
 455     }
 456     return( ( 1 << i) - 1 + bs_read( s, i ) );
 457 }
 458
 459 static inline int bs_read_se( bs_t *s )
 460 {
 461     int val = bs_read_ue( s );
 462
 463     return val&0x01 ? (val+1)/2 : -(val/2);
 464 }
 465
 466
 467 /*****************************************************************************
 468  * ParseNALBlock: parses annexB type NALs
 469  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 470  *****************************************************************************/
 471 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 472 {
 473     decoder_sys_t *p_sys = p_dec->p_sys;
 474     block_t *p_pic = NULL;
 475
 476     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 477     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 478
 479 #define OUTPUT \
 480     do {                                                      \
 481         p_pic = block_ChainGather( p_sys->p_frame );          \
 482         p_pic->i_length = 0;    /* FIXME */                   \
 483         p_pic->i_flags |= p_sys->i_frame_type;                \
 484                                                               \
 485         p_sys->i_frame_type = 0;                              \
 486         p_sys->p_frame = NULL;                                \
 487         p_sys->b_slice = VLC_FALSE;                           \
 488                                                               \
 489         if( ( p_pic->i_flags & BLOCK_FLAG_TYPE_I ) &&         \
 490               p_sys->p_sps && p_sys->p_pps )                  \
 491         {                                                     \
 492             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 493             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 494             p_sps->i_dts = p_pps->i_dts = p_pic->i_dts;       \
 495             p_sps->i_pts = p_pps->i_pts = p_pic->i_pts;       \
 496             block_ChainAppend( &p_sps, p_pps );               \
 497             block_ChainAppend( &p_sps, p_pic );               \
 498             p_pic = block_ChainGather( p_sps );               \
 499         }                                                     \
 500     } while(0)
 501
 502
 503     if( p_sys->b_slice && !p_sys->b_sps )
 504     {
 505         block_ChainRelease( p_sys->p_frame );
 506         msg_Warn( p_dec, "waiting for SPS" );
 507
 508         /* Reset context */
 509         p_sys->p_frame = NULL;
 510         p_sys->b_slice = VLC_FALSE;
 511     }
 512
 513     if( !p_sys->b_sps &&
 514         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 515     {
 516         p_sys->b_slice = VLC_TRUE;
 517         /* Fragment will be discarded later on */
 518     }
 519     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 520     {
 521         uint8_t *dec;
 522         int i_dec, i_first_mb, i_slice_type, i_frame_num;
 523         vlc_bool_t b_pic = VLC_FALSE;
 524         bs_t s;
 525
 526         /* do not convert the whole frame */
 527         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 528                          __MIN( p_frag->i_buffer - 5, 60 ) );
 529         bs_init( &s, dec, i_dec );
 530
 531         /* first_mb_in_slice */
 532         i_first_mb = bs_read_ue( &s );
 533
 534         /* slice_type */
 535         switch( (i_slice_type = bs_read_ue( &s )) )
 536         {
 537         case 0: case 5:
 538             p_sys->i_frame_type = BLOCK_FLAG_TYPE_P;
 539             break;
 540         case 1: case 6:
 541             p_sys->i_frame_type = BLOCK_FLAG_TYPE_B;
 542             break;
 543         case 2: case 7:
 544             p_sys->i_frame_type = BLOCK_FLAG_TYPE_I;
 545             break;
 546         case 3: case 8: /* SP */
 547             p_sys->i_frame_type = BLOCK_FLAG_TYPE_P;
 548             break;
 549         case 4: case 9:
 550             p_sys->i_frame_type = BLOCK_FLAG_TYPE_I;
 551             break;
 552         }
 553
 554         /* pic_parameter_set_id */
 555         bs_read_ue( &s );
 556         /* frame_num */
 557         i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 558
 559         /* Detection of the first VCL NAL unit of a primary coded picture
 560          * (cf. 7.4.1.2.4) */
 561         if( i_frame_num != p_sys->i_frame_num ||
 562             ( (i_nal_ref_idc != p_sys->i_nal_ref_idc) &&
 563               (!i_nal_ref_idc || !p_sys->i_nal_ref_idc) ) )
 564         {
 565             b_pic = VLC_TRUE;
 566         }
 567         p_sys->i_frame_num = i_frame_num;
 568         p_sys->i_nal_ref_idc = i_nal_ref_idc;
 569
 570         if( !p_sys->b_frame_mbs_only )
 571         {
 572             /* field_pic_flag */
 573             if( bs_read( &s, 1 ) )
 574             {
 575                 /* bottom_field_flag */
 576                 bs_read( &s, 1 );
 577             }
 578         }
 579
 580         if( i_nal_type == NAL_SLICE_IDR )
 581         {
 582             /* id_pic_id */
 583             int i_idr_pic_id = bs_read_ue( &s );
 584             if( p_sys->i_nal_type != i_nal_type ) b_pic = VLC_TRUE;
 585             if( p_sys->i_idr_pic_id != i_idr_pic_id ) b_pic = VLC_TRUE;
 586             p_sys->i_idr_pic_id = i_idr_pic_id;
 587         }
 588         p_sys->i_nal_type = i_nal_type;
 589
 590         if( b_pic && p_sys->b_slice ) OUTPUT;
 591
 592         p_sys->b_slice = VLC_TRUE;
 593
 594         free( dec );
 595     }
 596     else if( i_nal_type == NAL_SPS )
 597     {
 598         uint8_t *dec;
 599         int     i_dec;
 600         bs_t s;
 601         int i_tmp;
 602
 603         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 604
 605         p_sys->b_sps = VLC_TRUE;
 606
 607         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 608                          p_frag->i_buffer - 5 );
 609
 610         bs_init( &s, dec, i_dec );
 611         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 612         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 613         /* sps id */
 614         bs_read_ue( &s );
 615         /* Skip i_log2_max_frame_num */
 616         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 617         /* Read poc_type */
 618         i_tmp = bs_read_ue( &s );
 619         if( i_tmp == 0 )
 620         {
 621             /* skip i_log2_max_poc_lsb */
 622             bs_read_ue( &s );
 623         }
 624         else if( i_tmp == 1 )
 625         {
 626             int i_cycle;
 627             /* skip b_delta_pic_order_always_zero */
 628             bs_skip( &s, 1 );
 629             /* skip i_offset_for_non_ref_pic */
 630             bs_read_se( &s );
 631             /* skip i_offset_for_top_to_bottom_field */
 632             bs_read_se( &s );
 633             /* read i_num_ref_frames_in_poc_cycle */
 634             i_cycle = bs_read_ue( &s );
 635             if( i_cycle > 256 ) i_cycle = 256;
 636             while( i_cycle > 0 )
 637             {
 638                 /* skip i_offset_for_ref_frame */
 639                 bs_read_se(&s );
 640             }
 641         }
 642         /* i_num_ref_frames */
 643         bs_read_ue( &s );
 644         /* b_gaps_in_frame_num_value_allowed */
 645         bs_skip( &s, 1 );
 646
 647         /* Read size */
 648         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 649         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 650
 651         /* b_frame_mbs_only */
 652         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 653         if( p_sys->b_frame_mbs_only == 0 )
 654         {
 655             bs_skip( &s, 1 );
 656         }
 657         /* b_direct8x8_inference */
 658         bs_skip( &s, 1 );
 659
 660         /* crop */
 661         i_tmp = bs_read( &s, 1 );
 662         if( i_tmp )
 663         {
 664             /* left */
 665             bs_read_ue( &s );
 666             /* right */
 667             bs_read_ue( &s );
 668             /* top */
 669             bs_read_ue( &s );
 670             /* bottom */
 671             bs_read_ue( &s );
 672         }
 673
 674         /* vui */
 675         i_tmp = bs_read( &s, 1 );
 676         if( i_tmp )
 677         {
 678             /* read the aspect ratio part if any FIXME check it */
 679             i_tmp = bs_read( &s, 1 );
 680             if( i_tmp )
 681             {
 682                 static const struct { int w, h; } sar[14] =
 683                 {
 684                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 685                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 686                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 687                     { 64, 33 }, { 160,99 },
 688                 };
 689                 int i_sar = bs_read( &s, 8 );
 690                 int w, h;
 691
 692                 if( i_sar < 14 )
 693                 {
 694                     w = sar[i_sar].w;
 695                     h = sar[i_sar].h;
 696                 }
 697                 else
 698                 {
 699                     w = bs_read( &s, 16 );
 700                     h = bs_read( &s, 16 );
 701                 }
 702                 if( h != 0 )
 703                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 704                         h * p_dec->fmt_out.video.i_width /
 705                         p_dec->fmt_out.video.i_height;
 706                 else
 707                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 708             }
 709         }
 710
 711         free( dec );
 712
 713         if( p_sys->b_slice ) OUTPUT;
 714
 715         /* We have a new SPS */
 716         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 717         p_sys->p_sps = p_frag;
 718
 719         /* Do not append the SPS because we will insert it on keyframes */
 720         return p_pic;
 721     }
 722     else if( i_nal_type == NAL_PPS )
 723     {
 724         bs_t s;
 725         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 726
 727         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 728         p_sys->b_pps = VLC_TRUE;
 729
 730         /* TODO */
 731
 732         if( p_sys->b_slice ) OUTPUT;
 733
 734         /* We have a new PPS */
 735         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 736         p_sys->p_pps = p_frag;
 737
 738         /* Do not append the PPS because we will insert it on keyframes */
 739         return p_pic;
 740     }
 741     else if( i_nal_type == NAL_AU_DELIMITER ||
 742              i_nal_type == NAL_SEI ||
 743              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 744     {
 745         if( p_sys->b_slice ) OUTPUT;
 746     }
 747
 748 #undef OUTPUT
 749
 750     /* Append the block */
 751     block_ChainAppend( &p_sys->p_frame, p_frag );
 752
 753     return p_pic;
 754 }