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

   1 /*****************************************************************************
   2  * h264.c: h264/avc video packetizer
   3  *****************************************************************************
   4  * Copyright (C) 2001, 2002 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., 59 Temple Place - Suite 330, Boston, MA  02111, 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( _("H264 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 };
  88
  89 enum
  90 {
  91     STATE_NOSYNC,
  92     STATE_NEXT_SYNC,
  93 };
  94
  95 enum nal_unit_type_e
  96 {
  97     NAL_UNKNOWN = 0,
  98     NAL_SLICE   = 1,
  99     NAL_SLICE_DPA   = 2,
 100     NAL_SLICE_DPB   = 3,
 101     NAL_SLICE_DPC   = 4,
 102     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 103     NAL_SEI         = 6,    /* ref_idc == 0 */
 104     NAL_SPS         = 7,
 105     NAL_PPS         = 8,
 106     NAL_AU_DELIMITER= 9
 107     /* ref_idc == 0 for 6,9,10,11,12 */
 108 };
 109
 110 enum nal_priority_e
 111 {
 112     NAL_PRIORITY_DISPOSABLE = 0,
 113     NAL_PRIORITY_LOW        = 1,
 114     NAL_PRIORITY_HIGH       = 2,
 115     NAL_PRIORITY_HIGHEST    = 3,
 116 };
 117
 118 static block_t *ParseNALBlock( decoder_t *, block_t * );
 119
 120 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 121
 122 /*****************************************************************************
 123  * Open: probe the packetizer and return score
 124  *****************************************************************************/
 125 static int Open( vlc_object_t *p_this )
 126 {
 127     decoder_t     *p_dec = (decoder_t*)p_this;
 128     decoder_sys_t *p_sys;
 129
 130     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 131         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 132         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 133         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 134         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 135           p_dec->fmt_in.i_extra < 7 ) )
 136     {
 137         return VLC_EGENERIC;
 138     }
 139
 140     /* Allocate the memory needed to store the decoder's structure */
 141     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 142     {
 143         msg_Err( p_dec, "out of memory" );
 144         return VLC_EGENERIC;
 145     }
 146     p_sys->i_state = STATE_NOSYNC;
 147     p_sys->i_offset = 0;
 148     p_sys->startcode[0] = 0;
 149     p_sys->startcode[1] = 0;
 150     p_sys->startcode[2] = 0;
 151     p_sys->startcode[3] = 1;
 152     p_sys->bytestream = block_BytestreamInit( p_dec );
 153     p_sys->b_slice = VLC_FALSE;
 154     p_sys->p_frame = NULL;
 155     p_sys->b_sps   = VLC_FALSE;
 156     p_sys->b_pps   = VLC_FALSE;
 157     p_sys->p_sps   = 0;
 158     p_sys->p_pps   = 0;
 159
 160     p_sys->i_nal_type = -1;
 161     p_sys->i_nal_ref_idc = -1;
 162     p_sys->i_idr_pic_id = -1;
 163     p_sys->i_frame_num = -1;
 164
 165     /* Setup properties */
 166     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 167     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 168     /* FIXME: FFMPEG isn't happy at all if you leave this */
 169     if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 170     p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = 0;
 171
 172     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 173     {
 174         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 175         int i_sps, i_pps;
 176         int i;
 177
 178         /* Parse avcC */
 179         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 180
 181         /* Read SPS */
 182         i_sps = (*p++)&0x1f;
 183
 184         for( i = 0; i < i_sps; i++ )
 185         {
 186             int i_length = GetWBE( p );
 187             block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
 188
 189             p_sys->p_sps = block_Duplicate( p_sps );
 190             p_sps->i_pts = p_sps->i_dts = mdate();
 191             ParseNALBlock( p_dec, p_sps );
 192             p += 2 + i_length;
 193         }
 194         /* Read PPS */
 195         i_pps = *p++;
 196         for( i = 0; i < i_pps; i++ )
 197         {
 198             int i_length = GetWBE( p );
 199             block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
 200
 201             p_sys->p_pps = block_Duplicate( p_pps );
 202             p_pps->i_pts = p_pps->i_dts = mdate();
 203             ParseNALBlock( p_dec, p_pps );
 204             p += 2 + i_length;
 205         }
 206         msg_Dbg( p_dec, "avcC length size=%d sps=%d pps=%d",
 207                  p_sys->i_avcC_length_size, i_sps, i_pps );
 208
 209         /* Set callback */
 210         p_dec->pf_packetize = PacketizeAVC1;
 211     }
 212     else
 213     {
 214         /* Set callback */
 215         p_dec->pf_packetize = Packetize;
 216
 217         /* */
 218         if( p_dec->fmt_in.i_extra > 0 )
 219         {
 220             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 221             block_t *p_pic;
 222
 223             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 224                     p_dec->fmt_in.i_extra );
 225
 226             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 227             {
 228                 /* Should not occur because we should only receive SPS/PPS */
 229                 block_Release( p_pic );
 230             }
 231         }
 232     }
 233
 234     return VLC_SUCCESS;
 235 }
 236
 237 /*****************************************************************************
 238  * Close: clean up the packetizer
 239  *****************************************************************************/
 240 static void Close( vlc_object_t *p_this )
 241 {
 242     decoder_t *p_dec = (decoder_t*)p_this;
 243     decoder_sys_t *p_sys = p_dec->p_sys;
 244
 245     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 246     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 247     block_BytestreamRelease( &p_sys->bytestream );
 248     free( p_sys );
 249 }
 250
 251 /****************************************************************************
 252  * Packetize: the whole thing
 253  ****************************************************************************/
 254 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 255 {
 256     decoder_sys_t *p_sys = p_dec->p_sys;
 257     block_t       *p_pic;
 258
 259     if( !pp_block || !*pp_block ) return NULL;
 260
 261     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 262
 263     for( ;; )
 264     {
 265         switch( p_sys->i_state )
 266         {
 267             case STATE_NOSYNC:
 268                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 269                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 270                 {
 271                     p_sys->i_state = STATE_NEXT_SYNC;
 272                 }
 273
 274                 if( p_sys->i_offset )
 275                 {
 276                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 277                     p_sys->i_offset = 0;
 278                     block_BytestreamFlush( &p_sys->bytestream );
 279                 }
 280
 281                 if( p_sys->i_state != STATE_NEXT_SYNC )
 282                 {
 283                     /* Need more data */
 284                     return NULL;
 285                 }
 286
 287                 p_sys->i_offset = 1; /* To find next startcode */
 288
 289             case STATE_NEXT_SYNC:
 290                 /* Find the next startcode */
 291                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 292                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 293                 {
 294                     /* Need more data */
 295                     return NULL;
 296                 }
 297
 298                 /* Get the new fragment and set the pts/dts */
 299                 p_pic = block_New( p_dec, p_sys->i_offset );
 300                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 301                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 302
 303                 block_GetBytes( &p_sys->bytestream, p_pic->p_buffer,
 304                                 p_pic->i_buffer );
 305
 306                 if( !p_pic->p_buffer[p_pic->i_buffer-1] ) p_pic->i_buffer--;
 307                 p_sys->i_offset = 0;
 308
 309                 /* Parse the NAL */
 310                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 311                 {
 312                     p_sys->i_state = STATE_NOSYNC;
 313                     break;
 314                 }
 315 #if 0
 316                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 317                          p_pic->i_pts, p_pic->i_dts );
 318 #endif
 319
 320                 /* So p_block doesn't get re-added several times */
 321                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 322
 323                 p_sys->i_state = STATE_NOSYNC;
 324
 325                 return p_pic;
 326         }
 327     }
 328 }
 329
 330 /****************************************************************************
 331  * PacketizeAVC1: the whole thing
 332  ****************************************************************************/
 333 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 334 {
 335     decoder_sys_t *p_sys = p_dec->p_sys;
 336     block_t       *p_block;
 337     block_t       *p_ret = NULL;
 338     uint8_t       *p;
 339
 340     if( !pp_block || !*pp_block ) return NULL;
 341
 342     p_block = *pp_block;
 343     *pp_block = NULL;
 344
 345 #if 0
 346     if( //(p_block->i_flags & BLOCK_FLAG_TYPE_I) &&
 347         p_sys->p_sps && p_sys->p_pps )
 348     {
 349         block_t *p_pic;
 350         block_t *p_sps = block_Duplicate( p_sys->p_sps );
 351         block_t *p_pps = block_Duplicate( p_sys->p_pps );
 352         p_sps->i_dts = p_pps->i_dts = p_block->i_dts;
 353         p_sps->i_pts = p_pps->i_pts = p_block->i_pts;
 354         p_pic = ParseNALBlock( p_dec, p_sps );
 355         if( p_pic ) block_ChainAppend( &p_ret, p_pic );
 356         p_pic = ParseNALBlock( p_dec, p_pps );
 357         if( p_pic ) block_ChainAppend( &p_ret, p_pic );
 358     }
 359 #endif
 360
 361     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 362     {
 363         block_t *p_pic;
 364         int i_size = 0;
 365         int i;
 366
 367         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 368         {
 369             i_size = (i_size << 8) | (*p++);
 370         }
 371
 372         if( i_size > 0 )
 373         {
 374             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 375
 376             p_part->i_dts = p_block->i_dts;
 377             p_part->i_pts = p_block->i_pts;
 378
 379             /* Parse the NAL */
 380             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 381             {
 382                 block_ChainAppend( &p_ret, p_pic );
 383             }
 384         }
 385         p += i_size;
 386     }
 387
 388     return p_ret;
 389 }
 390
 391 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 392 {
 393     block_t *p_nal;
 394
 395     p_nal = block_New( p_dec, 3 + i_size );
 396
 397     /* Add start code */
 398     p_nal->p_buffer[0] = 0x00;
 399     p_nal->p_buffer[1] = 0x00;
 400     p_nal->p_buffer[2] = 0x01;
 401
 402     /* Copy nalu */
 403     memcpy( &p_nal->p_buffer[3], p, i_size );
 404
 405     return p_nal;
 406 }
 407
 408 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 409                              uint8_t *src, int i_src )
 410 {
 411     uint8_t *end = &src[i_src];
 412     uint8_t *dst = malloc( i_src );
 413
 414     *pp_ret = dst;
 415
 416     while( src < end )
 417     {
 418         if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 419             src[2] == 0x03 )
 420         {
 421             *dst++ = 0x00;
 422             *dst++ = 0x00;
 423
 424             src += 3;
 425             continue;
 426         }
 427         *dst++ = *src++;
 428     }
 429
 430     *pi_ret = dst - *pp_ret;
 431 }
 432
 433 static inline int bs_read_ue( bs_t *s )
 434 {
 435     int i = 0;
 436
 437     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 438     {
 439         i++;
 440     }
 441     return( ( 1 << i) - 1 + bs_read( s, i ) );
 442 }
 443
 444 static inline int bs_read_se( bs_t *s )
 445 {
 446     int val = bs_read_ue( s );
 447
 448     return val&0x01 ? (val+1)/2 : -(val/2);
 449 }
 450
 451
 452 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 453 {
 454     decoder_sys_t *p_sys = p_dec->p_sys;
 455     block_t *p_pic = NULL;
 456
 457     const int i_nal_ref_idc = (p_frag->p_buffer[3] >> 5)&0x03;
 458     const int i_nal_type = p_frag->p_buffer[3]&0x1f;
 459
 460 #define OUTPUT \
 461     do {                                                \
 462         p_pic = block_ChainGather( p_sys->p_frame );    \
 463         p_pic->i_length = 0;    /* FIXME */             \
 464                                                         \
 465         p_sys->p_frame = NULL;                          \
 466         p_sys->b_slice = VLC_FALSE;                     \
 467     } while(0)
 468
 469
 470     if( p_sys->b_slice && !p_sys->b_sps )
 471     {
 472         block_ChainRelease( p_sys->p_frame );
 473         msg_Warn( p_dec, "waiting for SPS" );
 474
 475         /* Reset context */
 476         p_sys->p_frame = NULL;
 477         p_sys->b_slice = VLC_FALSE;
 478     }
 479
 480     if( !p_sys->b_sps &&
 481         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 482     {
 483         p_sys->b_slice = VLC_TRUE;
 484         /* Fragment will be discarded later on */
 485     }
 486     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 487     {
 488         uint8_t *dec;
 489         int i_dec, i_first_mb, i_slice_type, i_frame_num, i_pic_flags = 0;
 490         vlc_bool_t b_pic = VLC_FALSE;
 491         bs_t s;
 492
 493         /* do not convert the whole frame */
 494         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[4],
 495                          __MIN( p_frag->i_buffer - 4, 60 ) );
 496         bs_init( &s, dec, i_dec );
 497
 498         /* first_mb_in_slice */
 499         i_first_mb = bs_read_ue( &s );
 500
 501         /* slice_type */
 502         switch( (i_slice_type = bs_read_ue( &s )) )
 503         {
 504             case 0: case 5:
 505                 i_pic_flags = BLOCK_FLAG_TYPE_P;
 506                 break;
 507             case 1: case 6:
 508                 i_pic_flags = BLOCK_FLAG_TYPE_B;
 509                 break;
 510             case 2: case 7:
 511                 i_pic_flags = BLOCK_FLAG_TYPE_I;
 512                 break;
 513             case 3: case 8: /* SP */
 514                 i_pic_flags = BLOCK_FLAG_TYPE_P;
 515                 break;
 516             case 4: case 9:
 517                 i_pic_flags = BLOCK_FLAG_TYPE_I;
 518                 break;
 519         }
 520
 521         /* pic_parameter_set_id */
 522         bs_read_ue( &s );
 523         /* frame_num */
 524         i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 525
 526         /* Detection of the first VCL NAL unit of a primary coded picture
 527          * (cf. 7.4.1.2.4) */
 528         if( i_frame_num != p_sys->i_frame_num ||
 529             ( (i_nal_ref_idc != p_sys->i_nal_ref_idc) &&
 530               (!i_nal_ref_idc || !p_sys->i_nal_ref_idc) ) )
 531         {
 532             b_pic = VLC_TRUE;
 533         }
 534         p_sys->i_frame_num = i_frame_num;
 535         p_sys->i_nal_ref_idc = i_nal_ref_idc;
 536
 537         if( !p_sys->b_frame_mbs_only )
 538         {
 539             /* field_pic_flag */
 540             if( bs_read( &s, 1 ) )
 541             {
 542                 /* bottom_field_flag */
 543                 bs_read( &s, 1 );
 544             }
 545         }
 546
 547         if( i_nal_type == NAL_SLICE_IDR )
 548         {
 549             /* id_pic_id */
 550             int i_idr_pic_id = bs_read_ue( &s );
 551             if( p_sys->i_nal_type != i_nal_type ) b_pic = VLC_TRUE;
 552             if( p_sys->i_idr_pic_id != i_idr_pic_id ) b_pic = VLC_TRUE;
 553             p_sys->i_idr_pic_id = i_idr_pic_id;
 554         }
 555         p_sys->i_nal_type = i_nal_type;
 556
 557         if( b_pic && p_sys->b_slice ) OUTPUT;
 558
 559         p_sys->b_slice = VLC_TRUE;
 560
 561         free( dec );
 562     }
 563     else if( i_nal_type == NAL_SPS )
 564     {
 565         uint8_t *dec;
 566         int     i_dec;
 567         bs_t s;
 568         int i_tmp;
 569
 570         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 571
 572         p_sys->b_sps = VLC_TRUE;
 573
 574         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[4],
 575                          p_frag->i_buffer - 4 );
 576
 577         bs_init( &s, dec, i_dec );
 578         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 579         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 580         /* sps id */
 581         bs_read_ue( &s );
 582         /* Skip i_log2_max_frame_num */
 583         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 584         /* Read poc_type */
 585         i_tmp = bs_read_ue( &s );
 586         if( i_tmp == 0 )
 587         {
 588             /* skip i_log2_max_poc_lsb */
 589             bs_read_ue( &s );
 590         }
 591         else if( i_tmp == 1 )
 592         {
 593             int i_cycle;
 594             /* skip b_delta_pic_order_always_zero */
 595             bs_skip( &s, 1 );
 596             /* skip i_offset_for_non_ref_pic */
 597             bs_read_se( &s );
 598             /* skip i_offset_for_top_to_bottom_field */
 599             bs_read_se( &s );
 600             /* read i_num_ref_frames_in_poc_cycle */
 601             i_cycle = bs_read_ue( &s );
 602             if( i_cycle > 256 ) i_cycle = 256;
 603             while( i_cycle > 0 )
 604             {
 605                 /* skip i_offset_for_ref_frame */
 606                 bs_read_se(&s );
 607             }
 608         }
 609         /* i_num_ref_frames */
 610         bs_read_ue( &s );
 611         /* b_gaps_in_frame_num_value_allowed */
 612         bs_skip( &s, 1 );
 613
 614         /* Read size */
 615         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 616         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 617
 618         /* b_frame_mbs_only */
 619         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 620         if( p_sys->b_frame_mbs_only == 0 )
 621         {
 622             bs_skip( &s, 1 );
 623         }
 624         /* b_direct8x8_inference */
 625         bs_skip( &s, 1 );
 626
 627         /* crop */
 628         i_tmp = bs_read( &s, 1 );
 629         if( i_tmp )
 630         {
 631             /* left */
 632             bs_read_ue( &s );
 633             /* right */
 634             bs_read_ue( &s );
 635             /* top */
 636             bs_read_ue( &s );
 637             /* bottom */
 638             bs_read_ue( &s );
 639         }
 640
 641         /* vui */
 642         i_tmp = bs_read( &s, 1 );
 643         if( i_tmp )
 644         {
 645             /* read the aspect ratio part if any FIXME check it */
 646             i_tmp = bs_read( &s, 1 );
 647             if( i_tmp )
 648             {
 649                 static const struct { int w, h; } sar[14] =
 650                 {
 651                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 652                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 653                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 654                     { 64, 33 }, { 160,99 },
 655                 };
 656                 int i_sar = bs_read( &s, 8 );
 657                 int w, h;
 658
 659                 if( i_sar < 14 )
 660                 {
 661                     w = sar[i_sar].w;
 662                     h = sar[i_sar].h;
 663                 }
 664                 else
 665                 {
 666                     w = bs_read( &s, 16 );
 667                     h = bs_read( &s, 16 );
 668                 }
 669                 if( h != 0 )
 670                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 671                         h * p_dec->fmt_out.video.i_width /
 672                         p_dec->fmt_out.video.i_height;
 673                 else
 674                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 675             }
 676         }
 677
 678         free( dec );
 679
 680
 681         if( p_sys->b_slice ) OUTPUT;
 682     }
 683     else if( i_nal_type == NAL_PPS )
 684     {
 685         bs_t s;
 686         bs_init( &s, &p_frag->p_buffer[4], p_frag->i_buffer - 4 );
 687
 688         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 689         p_sys->b_pps = VLC_TRUE;
 690
 691         /* TODO */
 692
 693         if( p_sys->b_slice ) OUTPUT;
 694     }
 695     else if( i_nal_type == NAL_AU_DELIMITER ||
 696              i_nal_type == NAL_SEI ||
 697              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 698     {
 699         if( p_sys->b_slice ) OUTPUT;
 700     }
 701
 702 #undef OUTPUT
 703
 704     /* Append the block */
 705     block_ChainAppend( &p_sys->p_frame, p_frag );
 706
 707     return p_pic;
 708 }