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  *          Derk-Jan Hartman <hartman at videolan dot org>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30
  31 #include <vlc/vlc.h>
  32 #include <vlc_sout.h>
  33 #include <vlc_codec.h>
  34 #include <vlc_block.h>
  35
  36 #include "vlc_block_helper.h"
  37 #include "vlc_bits.h"
  38
  39 /*****************************************************************************
  40  * Module descriptor
  41  *****************************************************************************/
  42 static int  Open ( vlc_object_t * );
  43 static void Close( vlc_object_t * );
  44
  45 vlc_module_begin();
  46     set_category( CAT_SOUT );
  47     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  48     set_description( _("H.264 video packetizer") );
  49     set_capability( "packetizer", 50 );
  50     set_callbacks( Open, Close );
  51 vlc_module_end();
  52
  53
  54 /****************************************************************************
  55  * Local prototypes
  56  ****************************************************************************/
  57 static block_t *Packetize( decoder_t *, block_t ** );
  58 static block_t *PacketizeAVC1( decoder_t *, block_t ** );
  59
  60 typedef struct
  61 {
  62     int i_nal_type;
  63     int i_nal_ref_idc;
  64
  65     int i_frame_type;
  66     int i_pic_parameter_set_id;
  67     int i_frame_num;
  68
  69     int i_field_pic_flag;
  70     int i_bottom_field_flag;
  71
  72     int i_idr_pic_id;
  73
  74     int i_pic_order_cnt_lsb;
  75     int i_delta_pic_order_cnt_bottom;
  76
  77     int i_delta_pic_order_cnt0;
  78     int i_delta_pic_order_cnt1;
  79 } slice_t;
  80
  81 struct decoder_sys_t
  82 {
  83     block_bytestream_t bytestream;
  84
  85     int     i_state;
  86     int     i_offset;
  87     uint8_t startcode[4];
  88
  89     vlc_bool_t b_slice;
  90     block_t    *p_frame;
  91
  92     vlc_bool_t   b_sps;
  93     vlc_bool_t   b_pps;
  94
  95     /* avcC data */
  96     int i_avcC_length_size;
  97     block_t *p_sps;
  98     block_t *p_pps;
  99
 100     /* Useful values of the Sequence Parameter Set */
 101     int i_log2_max_frame_num;
 102     int b_frame_mbs_only;
 103     int i_pic_order_cnt_type;
 104     int i_delta_pic_order_always_zero_flag;
 105     int i_log2_max_pic_order_cnt_lsb;
 106
 107     /* Value from Picture Parameter Set */
 108     int i_pic_order_present_flag;
 109
 110     /* Useful values of the Slice Header */
 111     slice_t slice;
 112 };
 113
 114 enum
 115 {
 116     STATE_NOSYNC,
 117     STATE_NEXT_SYNC,
 118 };
 119
 120 enum nal_unit_type_e
 121 {
 122     NAL_UNKNOWN = 0,
 123     NAL_SLICE   = 1,
 124     NAL_SLICE_DPA   = 2,
 125     NAL_SLICE_DPB   = 3,
 126     NAL_SLICE_DPC   = 4,
 127     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 128     NAL_SEI         = 6,    /* ref_idc == 0 */
 129     NAL_SPS         = 7,
 130     NAL_PPS         = 8,
 131     NAL_AU_DELIMITER= 9
 132     /* ref_idc == 0 for 6,9,10,11,12 */
 133 };
 134
 135 enum nal_priority_e
 136 {
 137     NAL_PRIORITY_DISPOSABLE = 0,
 138     NAL_PRIORITY_LOW        = 1,
 139     NAL_PRIORITY_HIGH       = 2,
 140     NAL_PRIORITY_HIGHEST    = 3,
 141 };
 142
 143 static block_t *ParseNALBlock( decoder_t *, block_t * );
 144
 145 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 146
 147 /*****************************************************************************
 148  * Open: probe the packetizer and return score
 149  * When opening after demux, the packetizer is only loaded AFTER the decoder
 150  * That means that what you set in fmt_out is ignored by the decoder in this special case
 151  *****************************************************************************/
 152 static int Open( vlc_object_t *p_this )
 153 {
 154     decoder_t     *p_dec = (decoder_t*)p_this;
 155     decoder_sys_t *p_sys;
 156
 157     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 158         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 159         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 160         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 161         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 162         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 163           p_dec->fmt_in.i_extra < 7 ) )
 164     {
 165         return VLC_EGENERIC;
 166     }
 167
 168     /* Allocate the memory needed to store the decoder's structure */
 169     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 170     {
 171         msg_Err( p_dec, "out of memory" );
 172         return VLC_EGENERIC;
 173     }
 174     p_sys->i_state = STATE_NOSYNC;
 175     p_sys->i_offset = 0;
 176     p_sys->startcode[0] = 0;
 177     p_sys->startcode[1] = 0;
 178     p_sys->startcode[2] = 0;
 179     p_sys->startcode[3] = 1;
 180     p_sys->bytestream = block_BytestreamInit( p_dec );
 181     p_sys->b_slice = VLC_FALSE;
 182     p_sys->p_frame = NULL;
 183     p_sys->b_sps   = VLC_FALSE;
 184     p_sys->b_pps   = VLC_FALSE;
 185     p_sys->p_sps   = 0;
 186     p_sys->p_pps   = 0;
 187
 188     p_sys->slice.i_nal_type = -1;
 189     p_sys->slice.i_nal_ref_idc = -1;
 190     p_sys->slice.i_idr_pic_id = -1;
 191     p_sys->slice.i_frame_num = -1;
 192     p_sys->slice.i_frame_type = 0;
 193     p_sys->slice.i_pic_parameter_set_id = -1;
 194     p_sys->slice.i_field_pic_flag = 0;
 195     p_sys->slice.i_bottom_field_flag = -1;
 196     p_sys->slice.i_pic_order_cnt_lsb = -1;
 197     p_sys->slice.i_delta_pic_order_cnt_bottom = -1;
 198
 199     /* Setup properties */
 200     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 201     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 202
 203     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 204     {
 205         /* This type of stream is produced by mp4 and matroska
 206          * when we want to store it in another streamformat, you need to convert
 207          * The fmt_in.p_extra should ALWAYS contain the avcC
 208          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 209         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 210         int i_sps, i_pps;
 211         int i;
 212
 213         /* Parse avcC */
 214         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 215
 216         /* Read SPS */
 217         i_sps = (*p++)&0x1f;
 218         for( i = 0; i < i_sps; i++ )
 219         {
 220             int i_length = GetWBE( p );
 221             block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
 222
 223             p_sys->p_sps = block_Duplicate( p_sps );
 224             p_sps->i_pts = p_sps->i_dts = mdate();
 225             ParseNALBlock( p_dec, p_sps );
 226             p += 2 + i_length;
 227         }
 228         /* Read PPS */
 229         i_pps = *p++;
 230         for( i = 0; i < i_pps; i++ )
 231         {
 232             int i_length = GetWBE( p );
 233             block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
 234
 235             p_sys->p_pps = block_Duplicate( p_pps );
 236             p_pps->i_pts = p_pps->i_dts = mdate();
 237             ParseNALBlock( p_dec, p_pps );
 238             p += 2 + i_length;
 239         }
 240         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 241                  p_sys->i_avcC_length_size, i_sps, i_pps );
 242
 243         /* FIXME: FFMPEG isn't happy at all if you leave this */
 244         if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 245         p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = NULL;
 246
 247         /* Set the new extradata */
 248         p_dec->fmt_out.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 249         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 250         memcpy( (uint8_t*)p_dec->fmt_out.p_extra, p_sys->p_sps->p_buffer, p_sys->p_sps->i_buffer);
 251         memcpy( (uint8_t*)p_dec->fmt_out.p_extra+p_sys->p_sps->i_buffer, p_sys->p_pps->p_buffer, p_sys->p_pps->i_buffer);
 252
 253         /* Set callback */
 254         p_dec->pf_packetize = PacketizeAVC1;
 255     }
 256     else
 257     {
 258         /* This type of stream contains data with 3 of 4 byte startcodes
 259          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 260          * The fmt_out.p_extra should be the same */
 261
 262         /* Set callback */
 263         p_dec->pf_packetize = Packetize;
 264
 265         /* */
 266         if( p_dec->fmt_in.i_extra > 0 )
 267         {
 268             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 269             block_t *p_pic;
 270
 271             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 272                     p_dec->fmt_in.i_extra );
 273
 274             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 275             {
 276                 /* Should not occur because we should only receive SPS/PPS */
 277                 block_Release( p_pic );
 278             }
 279         }
 280     }
 281
 282     return VLC_SUCCESS;
 283 }
 284
 285 /*****************************************************************************
 286  * Close: clean up the packetizer
 287  *****************************************************************************/
 288 static void Close( vlc_object_t *p_this )
 289 {
 290     decoder_t *p_dec = (decoder_t*)p_this;
 291     decoder_sys_t *p_sys = p_dec->p_sys;
 292
 293     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 294     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 295     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 296     block_BytestreamRelease( &p_sys->bytestream );
 297     free( p_sys );
 298 }
 299
 300 /****************************************************************************
 301  * Packetize: the whole thing
 302  * Search for the startcodes 3 or more bytes
 303  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 304  ****************************************************************************/
 305 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 306 {
 307     decoder_sys_t *p_sys = p_dec->p_sys;
 308     block_t       *p_pic;
 309
 310     if( !pp_block || !*pp_block )
 311         return NULL;
 312
 313     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 314     {
 315         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 316         {
 317             p_sys->i_state = STATE_NOSYNC;
 318             block_BytestreamFlush( &p_sys->bytestream );
 319
 320             if( p_sys->p_frame )
 321                 block_ChainRelease( p_sys->p_frame );
 322             p_sys->p_frame = NULL;
 323             p_sys->slice.i_frame_type = 0;
 324             p_sys->b_slice = VLC_FALSE;
 325         }
 326         block_Release( *pp_block );
 327         return NULL;
 328     }
 329
 330     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 331
 332     for( ;; )
 333     {
 334         switch( p_sys->i_state )
 335         {
 336             case STATE_NOSYNC:
 337                 /* Skip until 3 byte startcode 0 0 1 */
 338                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 339                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 340                 {
 341                     p_sys->i_state = STATE_NEXT_SYNC;
 342                 }
 343
 344                 if( p_sys->i_offset )
 345                 {
 346                     /* skip the data */
 347                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 348                     p_sys->i_offset = 0;
 349                     block_BytestreamFlush( &p_sys->bytestream );
 350                 }
 351
 352                 if( p_sys->i_state != STATE_NEXT_SYNC )
 353                 {
 354                     /* Need more data */
 355                     return NULL;
 356                 }
 357
 358                 p_sys->i_offset = 1; /* To find next startcode */
 359
 360             case STATE_NEXT_SYNC:
 361                 /* Find the next 3 byte startcode 0 0 1*/
 362                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 363                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 364                 {
 365                     /* Need more data */
 366                     return NULL;
 367                 }
 368
 369                 /* Get the new fragment and set the pts/dts */
 370                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 371                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 372                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 373                 /* Force 4 byte startcode 0 0 0 1 */
 374                 p_pic->p_buffer[0] = 0;
 375
 376                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 377                                 p_pic->i_buffer-1 );
 378
 379                 /* Remove trailing 0 bytes */
 380                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 381                     p_pic->i_buffer--;
 382                 p_sys->i_offset = 0;
 383
 384                 /* Parse the NAL */
 385                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 386                 {
 387                     p_sys->i_state = STATE_NOSYNC;
 388                     break;
 389                 }
 390 #if 0
 391                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 392                          p_pic->i_pts, p_pic->i_dts );
 393 #endif
 394
 395                 /* So p_block doesn't get re-added several times */
 396                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 397
 398                 p_sys->i_state = STATE_NOSYNC;
 399
 400                 return p_pic;
 401         }
 402     }
 403 }
 404
 405 /****************************************************************************
 406  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 407  * Will always use 4 byte 0 0 0 1 startcodes
 408  * Will prepend a SPS and PPS before each keyframe
 409  ****************************************************************************/
 410 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 411 {
 412     decoder_sys_t *p_sys = p_dec->p_sys;
 413     block_t       *p_block;
 414     block_t       *p_ret = NULL;
 415     uint8_t       *p;
 416
 417     if( !pp_block || !*pp_block )
 418         return NULL;
 419     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 420     {
 421         block_Release( *pp_block );
 422         return NULL;
 423     }
 424
 425     p_block = *pp_block;
 426     *pp_block = NULL;
 427
 428     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 429     {
 430         block_t *p_pic;
 431         int i_size = 0;
 432         int i;
 433
 434         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 435         {
 436             i_size = (i_size << 8) | (*p++);
 437         }
 438
 439         if( i_size > 0 )
 440         {
 441             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 442
 443             p_part->i_dts = p_block->i_dts;
 444             p_part->i_pts = p_block->i_pts;
 445
 446             /* Parse the NAL */
 447             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 448             {
 449                 block_ChainAppend( &p_ret, p_pic );
 450             }
 451         }
 452         p += i_size;
 453     }
 454     block_Release( p_block );
 455
 456     return p_ret;
 457 }
 458
 459 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 460 {
 461     block_t *p_nal;
 462
 463     p_nal = block_New( p_dec, 4 + i_size );
 464
 465     /* Add start code */
 466     p_nal->p_buffer[0] = 0x00;
 467     p_nal->p_buffer[1] = 0x00;
 468     p_nal->p_buffer[2] = 0x00;
 469     p_nal->p_buffer[3] = 0x01;
 470
 471     /* Copy nalu */
 472     memcpy( &p_nal->p_buffer[4], p, i_size );
 473
 474     return p_nal;
 475 }
 476
 477 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 478                              uint8_t *src, int i_src )
 479 {
 480     uint8_t *end = &src[i_src];
 481     uint8_t *dst = malloc( i_src );
 482
 483     *pp_ret = dst;
 484
 485     while( src < end )
 486     {
 487         if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 488             src[2] == 0x03 )
 489         {
 490             *dst++ = 0x00;
 491             *dst++ = 0x00;
 492
 493             src += 3;
 494             continue;
 495         }
 496         *dst++ = *src++;
 497     }
 498
 499     *pi_ret = dst - *pp_ret;
 500 }
 501
 502 static inline int bs_read_ue( bs_t *s )
 503 {
 504     int i = 0;
 505
 506     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 507     {
 508         i++;
 509     }
 510     return( ( 1 << i) - 1 + bs_read( s, i ) );
 511 }
 512
 513 static inline int bs_read_se( bs_t *s )
 514 {
 515     int val = bs_read_ue( s );
 516
 517     return val&0x01 ? (val+1)/2 : -(val/2);
 518 }
 519
 520
 521 /*****************************************************************************
 522  * ParseNALBlock: parses annexB type NALs
 523  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 524  *****************************************************************************/
 525 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 526 {
 527     decoder_sys_t *p_sys = p_dec->p_sys;
 528     block_t *p_pic = NULL;
 529
 530     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 531     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 532
 533 #define OUTPUT \
 534     do {                                                      \
 535         if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I) \
 536             break;                                            \
 537                                                               \
 538         if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->p_sps && p_sys->p_pps ) \
 539         { \
 540             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 541             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 542             p_sps->i_dts = p_sys->p_frame->i_dts;           \
 543             p_sps->i_pts = p_sys->p_frame->i_pts;           \
 544             block_ChainAppend( &p_sps, p_pps );               \
 545             block_ChainAppend( &p_sps, p_sys->p_frame );      \
 546             p_pic = block_ChainGather( p_sps );               \
 547         } else { \
 548             p_pic = block_ChainGather( p_sys->p_frame ); \
 549         } \
 550         p_pic->i_length = 0;    /* FIXME */                   \
 551         p_pic->i_flags |= p_sys->slice.i_frame_type;          \
 552             \
 553         p_sys->slice.i_frame_type = 0;                        \
 554         p_sys->p_frame = NULL;                                \
 555         p_sys->b_slice = VLC_FALSE;                           \
 556     } while(0)
 557
 558     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 559     {
 560         block_ChainRelease( p_sys->p_frame );
 561         msg_Warn( p_dec, "waiting for SPS/PPS" );
 562
 563         /* Reset context */
 564         p_sys->slice.i_frame_type = 0;
 565         p_sys->p_frame = NULL;
 566         p_sys->b_slice = VLC_FALSE;
 567     }
 568
 569     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 570         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 571     {
 572         p_sys->b_slice = VLC_TRUE;
 573         /* Fragment will be discarded later on */
 574     }
 575     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 576     {
 577         uint8_t *dec;
 578         int i_dec, i_first_mb, i_slice_type;
 579         slice_t slice;
 580         vlc_bool_t b_pic;
 581         bs_t s;
 582
 583         /* do not convert the whole frame */
 584         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 585                          __MIN( p_frag->i_buffer - 5, 60 ) );
 586         bs_init( &s, dec, i_dec );
 587
 588         /* first_mb_in_slice */
 589         i_first_mb = bs_read_ue( &s );
 590
 591         /* slice_type */
 592         switch( (i_slice_type = bs_read_ue( &s )) )
 593         {
 594         case 0: case 5:
 595             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 596             break;
 597         case 1: case 6:
 598             slice.i_frame_type = BLOCK_FLAG_TYPE_B;
 599             break;
 600         case 2: case 7:
 601             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 602             break;
 603         case 3: case 8: /* SP */
 604             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 605             break;
 606         case 4: case 9:
 607             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 608             break;
 609         default:
 610             slice.i_frame_type = 0;
 611             break;
 612         }
 613
 614         /* */
 615         slice.i_nal_type = i_nal_type;
 616         slice.i_nal_ref_idc = i_nal_ref_idc;
 617
 618         slice.i_pic_parameter_set_id = bs_read_ue( &s );
 619         slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 620
 621         slice.i_field_pic_flag = 0;
 622         slice.i_bottom_field_flag = -1;
 623         if( !p_sys->b_frame_mbs_only )
 624         {
 625             /* field_pic_flag */
 626             slice.i_field_pic_flag = bs_read( &s, 1 );
 627             if( slice.i_field_pic_flag )
 628                 slice.i_bottom_field_flag = bs_read( &s, 1 );
 629         }
 630
 631         slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
 632         if( slice.i_nal_type == NAL_SLICE_IDR )
 633             slice.i_idr_pic_id = bs_read_ue( &s );
 634
 635         slice.i_pic_order_cnt_lsb = -1;
 636         slice.i_delta_pic_order_cnt_bottom = -1;
 637         slice.i_delta_pic_order_cnt0 = 0;
 638         slice.i_delta_pic_order_cnt1 = 0;
 639         if( p_sys->i_pic_order_cnt_type == 0 )
 640         {
 641             slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
 642             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 643                 slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
 644         }
 645         else if( p_sys->i_pic_order_cnt_type == 1 && !p_sys->i_delta_pic_order_always_zero_flag )
 646         {
 647             slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
 648             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 649                 slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
 650         }
 651
 652         /* Detection of the first VCL NAL unit of a primary coded picture
 653          * (cf. 7.4.1.2.4) */
 654         b_pic = VLC_FALSE;
 655         if( slice.i_frame_num != p_sys->slice.i_frame_num ||
 656             slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
 657             slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
 658             slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
 659             b_pic = VLC_TRUE;
 660         if( slice.i_bottom_field_flag != -1 && p_sys->slice.i_bottom_field_flag != -1 && slice.i_bottom_field_flag != p_sys->slice.i_bottom_field_flag )
 661             b_pic = VLC_TRUE;
 662         if( p_sys->i_pic_order_cnt_type == 0 &&
 663             ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
 664               slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
 665             b_pic = VLC_TRUE;
 666         else if( p_sys->i_pic_order_cnt_type == 1 &&
 667                  ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
 668                    slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
 669             b_pic = VLC_TRUE;
 670         if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
 671             ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
 672                 b_pic = VLC_TRUE;
 673
 674         /* */
 675         p_sys->slice = slice;
 676
 677         if( b_pic && p_sys->b_slice )
 678             OUTPUT;
 679
 680         p_sys->b_slice = VLC_TRUE;
 681
 682         free( dec );
 683     }
 684     else if( i_nal_type == NAL_SPS )
 685     {
 686         uint8_t *dec;
 687         int     i_dec;
 688         bs_t s;
 689         int i_tmp;
 690
 691         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 692
 693         p_sys->b_sps = VLC_TRUE;
 694
 695         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 696                          p_frag->i_buffer - 5 );
 697
 698         bs_init( &s, dec, i_dec );
 699         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 700         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 701         /* sps id */
 702         bs_read_ue( &s );
 703         /* Skip i_log2_max_frame_num */
 704         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 705         if( p_sys->i_log2_max_frame_num > 12)
 706             p_sys->i_log2_max_frame_num = 12;
 707         /* Read poc_type */
 708         p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 709         if( p_sys->i_pic_order_cnt_type == 0 )
 710         {
 711             /* skip i_log2_max_poc_lsb */
 712             p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 713             if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 714                 p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 715         }
 716         else if( p_sys->i_pic_order_cnt_type == 1 )
 717         {
 718             int i_cycle;
 719             /* skip b_delta_pic_order_always_zero */
 720             p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 721             /* skip i_offset_for_non_ref_pic */
 722             bs_read_se( &s );
 723             /* skip i_offset_for_top_to_bottom_field */
 724             bs_read_se( &s );
 725             /* read i_num_ref_frames_in_poc_cycle */
 726             i_cycle = bs_read_ue( &s );
 727             if( i_cycle > 256 ) i_cycle = 256;
 728             while( i_cycle > 0 )
 729             {
 730                 /* skip i_offset_for_ref_frame */
 731                 bs_read_se(&s );
 732             }
 733         }
 734         /* i_num_ref_frames */
 735         bs_read_ue( &s );
 736         /* b_gaps_in_frame_num_value_allowed */
 737         bs_skip( &s, 1 );
 738
 739         /* Read size */
 740         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 741         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 742
 743         /* b_frame_mbs_only */
 744         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 745         if( p_sys->b_frame_mbs_only == 0 )
 746         {
 747             bs_skip( &s, 1 );
 748         }
 749         /* b_direct8x8_inference */
 750         bs_skip( &s, 1 );
 751
 752         /* crop */
 753         i_tmp = bs_read( &s, 1 );
 754         if( i_tmp )
 755         {
 756             /* left */
 757             bs_read_ue( &s );
 758             /* right */
 759             bs_read_ue( &s );
 760             /* top */
 761             bs_read_ue( &s );
 762             /* bottom */
 763             bs_read_ue( &s );
 764         }
 765
 766         /* vui */
 767         i_tmp = bs_read( &s, 1 );
 768         if( i_tmp )
 769         {
 770             /* read the aspect ratio part if any FIXME check it */
 771             i_tmp = bs_read( &s, 1 );
 772             if( i_tmp )
 773             {
 774                 static const struct { int w, h; } sar[14] =
 775                 {
 776                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 777                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 778                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 779                     { 64, 33 }, { 160,99 },
 780                 };
 781                 int i_sar = bs_read( &s, 8 );
 782                 int w, h;
 783
 784                 if( i_sar < 14 )
 785                 {
 786                     w = sar[i_sar].w;
 787                     h = sar[i_sar].h;
 788                 }
 789                 else
 790                 {
 791                     w = bs_read( &s, 16 );
 792                     h = bs_read( &s, 16 );
 793                 }
 794                 if( h != 0 )
 795                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 796                         h * p_dec->fmt_out.video.i_width /
 797                         p_dec->fmt_out.video.i_height;
 798                 else
 799                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 800             }
 801         }
 802
 803         free( dec );
 804
 805         if( p_sys->b_slice ) OUTPUT;
 806
 807         /* We have a new SPS */
 808         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 809         p_sys->p_sps = p_frag;
 810
 811         /* Do not append the SPS because we will insert it on keyframes */
 812         return p_pic;
 813     }
 814     else if( i_nal_type == NAL_PPS )
 815     {
 816         bs_t s;
 817
 818         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 819         bs_read_ue( &s ); // pps id
 820         bs_read_ue( &s ); // sps id
 821         bs_skip( &s, 1 ); // entropy coding mode flag
 822         p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 823
 824         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 825         p_sys->b_pps = VLC_TRUE;
 826
 827         /* TODO */
 828
 829         if( p_sys->b_slice ) OUTPUT;
 830
 831         /* We have a new PPS */
 832         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 833         p_sys->p_pps = p_frag;
 834
 835         /* Do not append the PPS because we will insert it on keyframes */
 836         return p_pic;
 837     }
 838     else if( i_nal_type == NAL_AU_DELIMITER ||
 839              i_nal_type == NAL_SEI ||
 840              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 841     {
 842         if( p_sys->b_slice ) OUTPUT;
 843     }
 844
 845 #undef OUTPUT
 846
 847     /* Append the block */
 848     block_ChainAppend( &p_sys->p_frame, p_frag );
 849
 850     return p_pic;
 851 }