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     vlc_bool_t   b_header;
  95
  96     /* avcC data */
  97     int i_avcC_length_size;
  98     block_t *p_sps;
  99     block_t *p_pps;
 100
 101     /* Useful values of the Sequence Parameter Set */
 102     int i_log2_max_frame_num;
 103     int b_frame_mbs_only;
 104     int i_pic_order_cnt_type;
 105     int i_delta_pic_order_always_zero_flag;
 106     int i_log2_max_pic_order_cnt_lsb;
 107
 108     /* Value from Picture Parameter Set */
 109     int i_pic_order_present_flag;
 110
 111     /* Useful values of the Slice Header */
 112     slice_t slice;
 113 };
 114
 115 enum
 116 {
 117     STATE_NOSYNC,
 118     STATE_NEXT_SYNC,
 119 };
 120
 121 enum nal_unit_type_e
 122 {
 123     NAL_UNKNOWN = 0,
 124     NAL_SLICE   = 1,
 125     NAL_SLICE_DPA   = 2,
 126     NAL_SLICE_DPB   = 3,
 127     NAL_SLICE_DPC   = 4,
 128     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 129     NAL_SEI         = 6,    /* ref_idc == 0 */
 130     NAL_SPS         = 7,
 131     NAL_PPS         = 8,
 132     NAL_AU_DELIMITER= 9
 133     /* ref_idc == 0 for 6,9,10,11,12 */
 134 };
 135
 136 enum nal_priority_e
 137 {
 138     NAL_PRIORITY_DISPOSABLE = 0,
 139     NAL_PRIORITY_LOW        = 1,
 140     NAL_PRIORITY_HIGH       = 2,
 141     NAL_PRIORITY_HIGHEST    = 3,
 142 };
 143
 144 static block_t *ParseNALBlock( decoder_t *, block_t * );
 145
 146 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 147
 148 /*****************************************************************************
 149  * Open: probe the packetizer and return score
 150  * When opening after demux, the packetizer is only loaded AFTER the decoder
 151  * That means that what you set in fmt_out is ignored by the decoder in this special case
 152  *****************************************************************************/
 153 static int Open( vlc_object_t *p_this )
 154 {
 155     decoder_t     *p_dec = (decoder_t*)p_this;
 156     decoder_sys_t *p_sys;
 157
 158     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 159         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 160         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 161         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 162         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 163         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 164           p_dec->fmt_in.i_extra < 7 ) )
 165     {
 166         return VLC_EGENERIC;
 167     }
 168
 169     /* Allocate the memory needed to store the decoder's structure */
 170     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 171     {
 172         msg_Err( p_dec, "out of memory" );
 173         return VLC_EGENERIC;
 174     }
 175     p_sys->i_state = STATE_NOSYNC;
 176     p_sys->i_offset = 0;
 177     p_sys->startcode[0] = 0;
 178     p_sys->startcode[1] = 0;
 179     p_sys->startcode[2] = 0;
 180     p_sys->startcode[3] = 1;
 181     p_sys->bytestream = block_BytestreamInit( p_dec );
 182     p_sys->b_slice = VLC_FALSE;
 183     p_sys->p_frame = NULL;
 184     p_sys->b_sps   = VLC_FALSE;
 185     p_sys->b_pps   = VLC_FALSE;
 186     p_sys->p_sps   = 0;
 187     p_sys->p_pps   = 0;
 188     p_sys->b_header= VLC_FALSE;
 189
 190     p_sys->slice.i_nal_type = -1;
 191     p_sys->slice.i_nal_ref_idc = -1;
 192     p_sys->slice.i_idr_pic_id = -1;
 193     p_sys->slice.i_frame_num = -1;
 194     p_sys->slice.i_frame_type = 0;
 195     p_sys->slice.i_pic_parameter_set_id = -1;
 196     p_sys->slice.i_field_pic_flag = 0;
 197     p_sys->slice.i_bottom_field_flag = -1;
 198     p_sys->slice.i_pic_order_cnt_lsb = -1;
 199     p_sys->slice.i_delta_pic_order_cnt_bottom = -1;
 200
 201     /* Setup properties */
 202     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 203     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 204
 205     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 206     {
 207         /* This type of stream is produced by mp4 and matroska
 208          * when we want to store it in another streamformat, you need to convert
 209          * The fmt_in.p_extra should ALWAYS contain the avcC
 210          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 211         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 212         int i_sps, i_pps;
 213         int i;
 214
 215         /* Parse avcC */
 216         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 217
 218         /* Read SPS */
 219         i_sps = (*p++)&0x1f;
 220         for( i = 0; i < i_sps; i++ )
 221         {
 222             int i_length = GetWBE( p );
 223             block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
 224
 225             p_sys->p_sps = block_Duplicate( p_sps );
 226             p_sps->i_pts = p_sps->i_dts = mdate();
 227             ParseNALBlock( p_dec, p_sps );
 228             p += 2 + i_length;
 229         }
 230         /* Read PPS */
 231         i_pps = *p++;
 232         for( i = 0; i < i_pps; i++ )
 233         {
 234             int i_length = GetWBE( p );
 235             block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
 236
 237             p_sys->p_pps = block_Duplicate( p_pps );
 238             p_pps->i_pts = p_pps->i_dts = mdate();
 239             ParseNALBlock( p_dec, p_pps );
 240             p += 2 + i_length;
 241         }
 242         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 243                  p_sys->i_avcC_length_size, i_sps, i_pps );
 244
 245         /* FIXME: FFMPEG isn't happy at all if you leave this */
 246         if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 247         p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = NULL;
 248
 249         /* Set the new extradata */
 250         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 251         if( p_dec->fmt_out.p_extra )
 252         {
 253             p_dec->fmt_out.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 254             memcpy( (uint8_t*)p_dec->fmt_out.p_extra, p_sys->p_sps->p_buffer, p_sys->p_sps->i_buffer);
 255             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);
 256             p_sys->b_header = VLC_TRUE;
 257         }
 258         /* Set callback */
 259         p_dec->pf_packetize = PacketizeAVC1;
 260     }
 261     else
 262     {
 263         /* This type of stream contains data with 3 of 4 byte startcodes
 264          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 265          * The fmt_out.p_extra should be the same */
 266
 267         /* Set callback */
 268         p_dec->pf_packetize = Packetize;
 269
 270         /* */
 271         if( p_dec->fmt_in.i_extra > 0 )
 272         {
 273             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 274             block_t *p_pic;
 275
 276             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 277                     p_dec->fmt_in.i_extra );
 278
 279             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 280             {
 281                 /* Should not occur because we should only receive SPS/PPS */
 282                 block_Release( p_pic );
 283             }
 284         }
 285     }
 286
 287     return VLC_SUCCESS;
 288 }
 289
 290 /*****************************************************************************
 291  * Close: clean up the packetizer
 292  *****************************************************************************/
 293 static void Close( vlc_object_t *p_this )
 294 {
 295     decoder_t *p_dec = (decoder_t*)p_this;
 296     decoder_sys_t *p_sys = p_dec->p_sys;
 297
 298     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 299     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 300     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 301     block_BytestreamRelease( &p_sys->bytestream );
 302     free( p_sys );
 303 }
 304
 305 /****************************************************************************
 306  * Packetize: the whole thing
 307  * Search for the startcodes 3 or more bytes
 308  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 309  ****************************************************************************/
 310 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 311 {
 312     decoder_sys_t *p_sys = p_dec->p_sys;
 313     block_t       *p_pic;
 314
 315     if( !pp_block || !*pp_block )
 316         return NULL;
 317
 318     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 319     {
 320         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 321         {
 322             p_sys->i_state = STATE_NOSYNC;
 323             block_BytestreamFlush( &p_sys->bytestream );
 324
 325             if( p_sys->p_frame )
 326                 block_ChainRelease( p_sys->p_frame );
 327             p_sys->p_frame = NULL;
 328             p_sys->slice.i_frame_type = 0;
 329             p_sys->b_slice = VLC_FALSE;
 330         }
 331         block_Release( *pp_block );
 332         return NULL;
 333     }
 334
 335     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 336
 337     for( ;; )
 338     {
 339         switch( p_sys->i_state )
 340         {
 341             case STATE_NOSYNC:
 342                 /* Skip until 3 byte startcode 0 0 1 */
 343                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 344                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 345                 {
 346                     p_sys->i_state = STATE_NEXT_SYNC;
 347                 }
 348
 349                 if( p_sys->i_offset )
 350                 {
 351                     /* skip the data */
 352                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 353                     p_sys->i_offset = 0;
 354                     block_BytestreamFlush( &p_sys->bytestream );
 355                 }
 356
 357                 if( p_sys->i_state != STATE_NEXT_SYNC )
 358                 {
 359                     /* Need more data */
 360                     return NULL;
 361                 }
 362
 363                 p_sys->i_offset = 1; /* To find next startcode */
 364
 365             case STATE_NEXT_SYNC:
 366                 /* Find the next 3 byte startcode 0 0 1*/
 367                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 368                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 369                 {
 370                     /* Need more data */
 371                     return NULL;
 372                 }
 373
 374                 /* Get the new fragment and set the pts/dts */
 375                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 376                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 377                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 378                 /* Force 4 byte startcode 0 0 0 1 */
 379                 p_pic->p_buffer[0] = 0;
 380
 381                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 382                                 p_pic->i_buffer-1 );
 383
 384                 /* Remove trailing 0 bytes */
 385                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 386                     p_pic->i_buffer--;
 387                 p_sys->i_offset = 0;
 388
 389                 /* Parse the NAL */
 390                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 391                 {
 392                     p_sys->i_state = STATE_NOSYNC;
 393                     break;
 394                 }
 395 #if 0
 396                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 397                          p_pic->i_pts, p_pic->i_dts );
 398 #endif
 399
 400                 /* So p_block doesn't get re-added several times */
 401                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 402
 403                 p_sys->i_state = STATE_NOSYNC;
 404
 405                 return p_pic;
 406         }
 407     }
 408 }
 409
 410 /****************************************************************************
 411  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 412  * Will always use 4 byte 0 0 0 1 startcodes
 413  * Will prepend a SPS and PPS before each keyframe
 414  ****************************************************************************/
 415 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 416 {
 417     decoder_sys_t *p_sys = p_dec->p_sys;
 418     block_t       *p_block;
 419     block_t       *p_ret = NULL;
 420     uint8_t       *p;
 421
 422     if( !pp_block || !*pp_block )
 423         return NULL;
 424     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 425     {
 426         block_Release( *pp_block );
 427         return NULL;
 428     }
 429
 430     p_block = *pp_block;
 431     *pp_block = NULL;
 432
 433     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 434     {
 435         block_t *p_pic;
 436         int i_size = 0;
 437         int i;
 438
 439         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 440         {
 441             i_size = (i_size << 8) | (*p++);
 442         }
 443
 444         if( i_size > 0 )
 445         {
 446             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 447
 448             p_part->i_dts = p_block->i_dts;
 449             p_part->i_pts = p_block->i_pts;
 450
 451             /* Parse the NAL */
 452             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 453             {
 454                 block_ChainAppend( &p_ret, p_pic );
 455             }
 456         }
 457         p += i_size;
 458     }
 459     block_Release( p_block );
 460
 461     return p_ret;
 462 }
 463
 464 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 465 {
 466     block_t *p_nal;
 467
 468     p_nal = block_New( p_dec, 4 + i_size );
 469
 470     /* Add start code */
 471     p_nal->p_buffer[0] = 0x00;
 472     p_nal->p_buffer[1] = 0x00;
 473     p_nal->p_buffer[2] = 0x00;
 474     p_nal->p_buffer[3] = 0x01;
 475
 476     /* Copy nalu */
 477     memcpy( &p_nal->p_buffer[4], p, i_size );
 478
 479     return p_nal;
 480 }
 481
 482 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 483                              uint8_t *src, int i_src )
 484 {
 485     uint8_t *end = &src[i_src];
 486     uint8_t *dst = malloc( i_src );
 487
 488     if( dst )
 489     {
 490         *pp_ret = dst;
 491
 492         while( src < end )
 493         {
 494             if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 495                 src[2] == 0x03 )
 496             {
 497                 *dst++ = 0x00;
 498                 *dst++ = 0x00;
 499
 500                 src += 3;
 501                 continue;
 502             }
 503             *dst++ = *src++;
 504         }
 505     }
 506     *pi_ret = dst - *pp_ret;
 507 }
 508
 509 static inline int bs_read_ue( bs_t *s )
 510 {
 511     int i = 0;
 512
 513     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 514     {
 515         i++;
 516     }
 517     return( ( 1 << i) - 1 + bs_read( s, i ) );
 518 }
 519
 520 static inline int bs_read_se( bs_t *s )
 521 {
 522     int val = bs_read_ue( s );
 523
 524     return val&0x01 ? (val+1)/2 : -(val/2);
 525 }
 526
 527 /*****************************************************************************
 528  * ParseNALBlock: parses annexB type NALs
 529  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 530  *****************************************************************************/
 531 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 532 {
 533     decoder_sys_t *p_sys = p_dec->p_sys;
 534     block_t *p_pic = NULL;
 535
 536     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 537     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 538
 539 #define OUTPUT \
 540     do {                                                      \
 541         if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I) \
 542             break;                                            \
 543                                                               \
 544         if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->p_sps && p_sys->p_pps ) \
 545         { \
 546             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 547             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 548             p_sps->i_dts = p_sys->p_frame->i_dts;           \
 549             p_sps->i_pts = p_sys->p_frame->i_pts;           \
 550             block_ChainAppend( &p_sps, p_pps );               \
 551             block_ChainAppend( &p_sps, p_sys->p_frame );      \
 552             p_sys->b_header = VLC_TRUE;                       \
 553             p_pic = block_ChainGather( p_sps );               \
 554         } else { \
 555             p_pic = block_ChainGather( p_sys->p_frame ); \
 556         } \
 557         p_pic->i_length = 0;    /* FIXME */                   \
 558         p_pic->i_flags |= p_sys->slice.i_frame_type;          \
 559             \
 560         p_sys->slice.i_frame_type = 0;                        \
 561         p_sys->p_frame = NULL;                                \
 562         p_sys->b_slice = VLC_FALSE;                           \
 563     } while(0)
 564
 565     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 566     {
 567         block_ChainRelease( p_sys->p_frame );
 568         msg_Warn( p_dec, "waiting for SPS/PPS" );
 569
 570         /* Reset context */
 571         p_sys->slice.i_frame_type = 0;
 572         p_sys->p_frame = NULL;
 573         p_sys->b_slice = VLC_FALSE;
 574     }
 575
 576     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 577         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 578     {
 579         p_sys->b_slice = VLC_TRUE;
 580         /* Fragment will be discarded later on */
 581     }
 582     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 583     {
 584         uint8_t *dec = NULL;
 585         int i_dec = 0, i_first_mb, i_slice_type;
 586         slice_t slice;
 587         vlc_bool_t b_pic;
 588         bs_t s;
 589
 590         /* do not convert the whole frame */
 591         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 592                          __MIN( p_frag->i_buffer - 5, 60 ) );
 593         bs_init( &s, dec, i_dec );
 594
 595         /* first_mb_in_slice */
 596         i_first_mb = bs_read_ue( &s );
 597
 598         /* slice_type */
 599         switch( (i_slice_type = bs_read_ue( &s )) )
 600         {
 601         case 0: case 5:
 602             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 603             break;
 604         case 1: case 6:
 605             slice.i_frame_type = BLOCK_FLAG_TYPE_B;
 606             break;
 607         case 2: case 7:
 608             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 609             break;
 610         case 3: case 8: /* SP */
 611             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 612             break;
 613         case 4: case 9:
 614             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 615             break;
 616         default:
 617             slice.i_frame_type = 0;
 618             break;
 619         }
 620
 621         /* */
 622         slice.i_nal_type = i_nal_type;
 623         slice.i_nal_ref_idc = i_nal_ref_idc;
 624
 625         slice.i_pic_parameter_set_id = bs_read_ue( &s );
 626         slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 627
 628         slice.i_field_pic_flag = 0;
 629         slice.i_bottom_field_flag = -1;
 630         if( !p_sys->b_frame_mbs_only )
 631         {
 632             /* field_pic_flag */
 633             slice.i_field_pic_flag = bs_read( &s, 1 );
 634             if( slice.i_field_pic_flag )
 635                 slice.i_bottom_field_flag = bs_read( &s, 1 );
 636         }
 637
 638         slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
 639         if( slice.i_nal_type == NAL_SLICE_IDR )
 640             slice.i_idr_pic_id = bs_read_ue( &s );
 641
 642         slice.i_pic_order_cnt_lsb = -1;
 643         slice.i_delta_pic_order_cnt_bottom = -1;
 644         slice.i_delta_pic_order_cnt0 = 0;
 645         slice.i_delta_pic_order_cnt1 = 0;
 646         if( p_sys->i_pic_order_cnt_type == 0 )
 647         {
 648             slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
 649             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 650                 slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
 651         }
 652         else if( (p_sys->i_pic_order_cnt_type == 1) &&
 653                  (!p_sys->i_delta_pic_order_always_zero_flag) )
 654         {
 655             slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
 656             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 657                 slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
 658         }
 659
 660         /* Detection of the first VCL NAL unit of a primary coded picture
 661          * (cf. 7.4.1.2.4) */
 662         b_pic = VLC_FALSE;
 663         if( slice.i_frame_num != p_sys->slice.i_frame_num ||
 664             slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
 665             slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
 666             slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
 667             b_pic = VLC_TRUE;
 668         if( (slice.i_bottom_field_flag != -1) &&
 669             (p_sys->slice.i_bottom_field_flag != -1) &&
 670             (slice.i_bottom_field_flag != p_sys->slice.i_bottom_field_flag) )
 671             b_pic = VLC_TRUE;
 672         if( p_sys->i_pic_order_cnt_type == 0 &&
 673             ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
 674               slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
 675             b_pic = VLC_TRUE;
 676         else if( p_sys->i_pic_order_cnt_type == 1 &&
 677                  ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
 678                    slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
 679             b_pic = VLC_TRUE;
 680         if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
 681             ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
 682                 b_pic = VLC_TRUE;
 683
 684         /* */
 685         p_sys->slice = slice;
 686
 687         if( b_pic && p_sys->b_slice )
 688             OUTPUT;
 689
 690         p_sys->b_slice = VLC_TRUE;
 691
 692         free( dec );
 693     }
 694     else if( i_nal_type == NAL_SPS )
 695     {
 696         uint8_t *dec = NULL;
 697         int     i_dec = 0;
 698         bs_t s;
 699         int i_tmp;
 700
 701         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 702
 703         p_sys->b_sps = VLC_TRUE;
 704
 705         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 706                          p_frag->i_buffer - 5 );
 707
 708         bs_init( &s, dec, i_dec );
 709         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 710         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 711         /* sps id */
 712         bs_read_ue( &s );
 713         /* Skip i_log2_max_frame_num */
 714         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 715         if( p_sys->i_log2_max_frame_num > 12)
 716             p_sys->i_log2_max_frame_num = 12;
 717         /* Read poc_type */
 718         p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 719         if( p_sys->i_pic_order_cnt_type == 0 )
 720         {
 721             /* skip i_log2_max_poc_lsb */
 722             p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 723             if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 724                 p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 725         }
 726         else if( p_sys->i_pic_order_cnt_type == 1 )
 727         {
 728             int i_cycle;
 729             /* skip b_delta_pic_order_always_zero */
 730             p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 731             /* skip i_offset_for_non_ref_pic */
 732             bs_read_se( &s );
 733             /* skip i_offset_for_top_to_bottom_field */
 734             bs_read_se( &s );
 735             /* read i_num_ref_frames_in_poc_cycle */
 736             i_cycle = bs_read_ue( &s );
 737             if( i_cycle > 256 ) i_cycle = 256;
 738             while( i_cycle > 0 )
 739             {
 740                 /* skip i_offset_for_ref_frame */
 741                 bs_read_se(&s );
 742             }
 743         }
 744         /* i_num_ref_frames */
 745         bs_read_ue( &s );
 746         /* b_gaps_in_frame_num_value_allowed */
 747         bs_skip( &s, 1 );
 748
 749         /* Read size */
 750         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 751         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 752
 753         /* b_frame_mbs_only */
 754         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 755         if( p_sys->b_frame_mbs_only == 0 )
 756         {
 757             bs_skip( &s, 1 );
 758         }
 759         /* b_direct8x8_inference */
 760         bs_skip( &s, 1 );
 761
 762         /* crop */
 763         i_tmp = bs_read( &s, 1 );
 764         if( i_tmp )
 765         {
 766             /* left */
 767             bs_read_ue( &s );
 768             /* right */
 769             bs_read_ue( &s );
 770             /* top */
 771             bs_read_ue( &s );
 772             /* bottom */
 773             bs_read_ue( &s );
 774         }
 775
 776         /* vui */
 777         i_tmp = bs_read( &s, 1 );
 778         if( i_tmp )
 779         {
 780             /* read the aspect ratio part if any FIXME check it */
 781             i_tmp = bs_read( &s, 1 );
 782             if( i_tmp )
 783             {
 784                 static const struct { int w, h; } sar[14] =
 785                 {
 786                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 787                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 788                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 789                     { 64, 33 }, { 160,99 },
 790                 };
 791                 int i_sar = bs_read( &s, 8 );
 792                 int w, h;
 793
 794                 if( i_sar < 14 )
 795                 {
 796                     w = sar[i_sar].w;
 797                     h = sar[i_sar].h;
 798                 }
 799                 else
 800                 {
 801                     w = bs_read( &s, 16 );
 802                     h = bs_read( &s, 16 );
 803                 }
 804                 if( h != 0 )
 805                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 806                         h * p_dec->fmt_out.video.i_width /
 807                         p_dec->fmt_out.video.i_height;
 808                 else
 809                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 810             }
 811         }
 812
 813         free( dec );
 814
 815         if( p_sys->b_slice ) OUTPUT;
 816
 817         /* We have a new SPS */
 818         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 819         p_sys->p_sps = p_frag;
 820
 821         /* Do not append the SPS because we will insert it on keyframes */
 822         return p_pic;
 823     }
 824     else if( i_nal_type == NAL_PPS )
 825     {
 826         bs_t s;
 827
 828         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 829         bs_read_ue( &s ); // pps id
 830         bs_read_ue( &s ); // sps id
 831         bs_skip( &s, 1 ); // entropy coding mode flag
 832         p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 833
 834         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 835         p_sys->b_pps = VLC_TRUE;
 836
 837         /* TODO */
 838
 839         if( p_sys->b_slice ) OUTPUT;
 840
 841         /* We have a new PPS */
 842         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 843         p_sys->p_pps = p_frag;
 844
 845         /* Do not append the PPS because we will insert it on keyframes */
 846         return p_pic;
 847     }
 848     else if( i_nal_type == NAL_AU_DELIMITER ||
 849              i_nal_type == NAL_SEI ||
 850              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 851     {
 852         if( p_sys->b_slice ) OUTPUT;
 853     }
 854
 855 #undef OUTPUT
 856
 857     /* Append the block */
 858     block_ChainAppend( &p_sys->p_frame, p_frag );
 859
 860     return p_pic;
 861 }