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 #include <stdlib.h>                                      /* malloc(), free() */
  31
  32 #include <vlc/vlc.h>
  33 #include <vlc_sout.h>
  34 #include <vlc_codec.h>
  35 #include <vlc_block.h>
  36
  37 #include "vlc_block_helper.h"
  38 #include "vlc_bits.h"
  39
  40 /*****************************************************************************
  41  * Module descriptor
  42  *****************************************************************************/
  43 static int  Open ( vlc_object_t * );
  44 static void Close( vlc_object_t * );
  45
  46 vlc_module_begin();
  47     set_category( CAT_SOUT );
  48     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  49     set_description( _("H.264 video packetizer") );
  50     set_capability( "packetizer", 50 );
  51     set_callbacks( Open, Close );
  52 vlc_module_end();
  53
  54
  55 /****************************************************************************
  56  * Local prototypes
  57  ****************************************************************************/
  58 static block_t *Packetize( decoder_t *, block_t ** );
  59 static block_t *PacketizeAVC1( decoder_t *, block_t ** );
  60
  61 typedef struct
  62 {
  63     int i_nal_type;
  64     int i_nal_ref_idc;
  65
  66     int i_frame_type;
  67     int i_pic_parameter_set_id;
  68     int i_frame_num;
  69
  70     int i_field_pic_flag;
  71     int i_bottom_field_flag;
  72
  73     int i_idr_pic_id;
  74
  75     int i_pic_order_cnt_lsb;
  76     int i_delta_pic_order_cnt_bottom;
  77
  78     int i_delta_pic_order_cnt0;
  79     int i_delta_pic_order_cnt1;
  80 } slice_t;
  81
  82 struct decoder_sys_t
  83 {
  84     block_bytestream_t bytestream;
  85
  86     int     i_state;
  87     int     i_offset;
  88     uint8_t startcode[4];
  89
  90     vlc_bool_t b_slice;
  91     block_t    *p_frame;
  92
  93     vlc_bool_t   b_sps;
  94     vlc_bool_t   b_pps;
  95     vlc_bool_t   b_header;
  96
  97     /* avcC data */
  98     int i_avcC_length_size;
  99     block_t *p_sps;
 100     block_t *p_pps;
 101
 102     /* Useful values of the Sequence Parameter Set */
 103     int i_log2_max_frame_num;
 104     int b_frame_mbs_only;
 105     int i_pic_order_cnt_type;
 106     int i_delta_pic_order_always_zero_flag;
 107     int i_log2_max_pic_order_cnt_lsb;
 108
 109     /* Value from Picture Parameter Set */
 110     int i_pic_order_present_flag;
 111
 112     /* Useful values of the Slice Header */
 113     slice_t slice;
 114 };
 115
 116 enum
 117 {
 118     STATE_NOSYNC,
 119     STATE_NEXT_SYNC,
 120 };
 121
 122 enum nal_unit_type_e
 123 {
 124     NAL_UNKNOWN = 0,
 125     NAL_SLICE   = 1,
 126     NAL_SLICE_DPA   = 2,
 127     NAL_SLICE_DPB   = 3,
 128     NAL_SLICE_DPC   = 4,
 129     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 130     NAL_SEI         = 6,    /* ref_idc == 0 */
 131     NAL_SPS         = 7,
 132     NAL_PPS         = 8,
 133     NAL_AU_DELIMITER= 9
 134     /* ref_idc == 0 for 6,9,10,11,12 */
 135 };
 136
 137 enum nal_priority_e
 138 {
 139     NAL_PRIORITY_DISPOSABLE = 0,
 140     NAL_PRIORITY_LOW        = 1,
 141     NAL_PRIORITY_HIGH       = 2,
 142     NAL_PRIORITY_HIGHEST    = 3,
 143 };
 144
 145 static block_t *ParseNALBlock( decoder_t *, block_t * );
 146
 147 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 148
 149 /*****************************************************************************
 150  * Open: probe the packetizer and return score
 151  * When opening after demux, the packetizer is only loaded AFTER the decoder
 152  * That means that what you set in fmt_out is ignored by the decoder in this special case
 153  *****************************************************************************/
 154 static int Open( vlc_object_t *p_this )
 155 {
 156     decoder_t     *p_dec = (decoder_t*)p_this;
 157     decoder_sys_t *p_sys;
 158
 159     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 160         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 161         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 162         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 163         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 164         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 165           p_dec->fmt_in.i_extra < 7 ) )
 166     {
 167         return VLC_EGENERIC;
 168     }
 169
 170     /* Allocate the memory needed to store the decoder's structure */
 171     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 172     {
 173         msg_Err( p_dec, "out of memory" );
 174         return VLC_EGENERIC;
 175     }
 176     p_sys->i_state = STATE_NOSYNC;
 177     p_sys->i_offset = 0;
 178     p_sys->startcode[0] = 0;
 179     p_sys->startcode[1] = 0;
 180     p_sys->startcode[2] = 0;
 181     p_sys->startcode[3] = 1;
 182     p_sys->bytestream = block_BytestreamInit( p_dec );
 183     p_sys->b_slice = VLC_FALSE;
 184     p_sys->p_frame = NULL;
 185     p_sys->b_sps   = VLC_FALSE;
 186     p_sys->b_pps   = VLC_FALSE;
 187     p_sys->p_sps   = 0;
 188     p_sys->p_pps   = 0;
 189     p_sys->b_header= VLC_FALSE;
 190
 191     p_sys->slice.i_nal_type = -1;
 192     p_sys->slice.i_nal_ref_idc = -1;
 193     p_sys->slice.i_idr_pic_id = -1;
 194     p_sys->slice.i_frame_num = -1;
 195     p_sys->slice.i_frame_type = 0;
 196     p_sys->slice.i_pic_parameter_set_id = -1;
 197     p_sys->slice.i_field_pic_flag = 0;
 198     p_sys->slice.i_bottom_field_flag = -1;
 199     p_sys->slice.i_pic_order_cnt_lsb = -1;
 200     p_sys->slice.i_delta_pic_order_cnt_bottom = -1;
 201
 202     /* Setup properties */
 203     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 204     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 205
 206     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 207     {
 208         /* This type of stream is produced by mp4 and matroska
 209          * when we want to store it in another streamformat, you need to convert
 210          * The fmt_in.p_extra should ALWAYS contain the avcC
 211          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 212         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 213         int i_sps, i_pps;
 214         int i;
 215
 216         /* Parse avcC */
 217         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 218
 219         /* Read SPS */
 220         i_sps = (*p++)&0x1f;
 221         for( i = 0; i < i_sps; i++ )
 222         {
 223             int i_length = GetWBE( p );
 224             block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
 225
 226             p_sys->p_sps = block_Duplicate( p_sps );
 227             p_sps->i_pts = p_sps->i_dts = mdate();
 228             ParseNALBlock( p_dec, p_sps );
 229             p += 2 + i_length;
 230         }
 231         /* Read PPS */
 232         i_pps = *p++;
 233         for( i = 0; i < i_pps; i++ )
 234         {
 235             int i_length = GetWBE( p );
 236             block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
 237
 238             p_sys->p_pps = block_Duplicate( p_pps );
 239             p_pps->i_pts = p_pps->i_dts = mdate();
 240             ParseNALBlock( p_dec, p_pps );
 241             p += 2 + i_length;
 242         }
 243         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 244                  p_sys->i_avcC_length_size, i_sps, i_pps );
 245
 246         /* FIXME: FFMPEG isn't happy at all if you leave this */
 247         if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 248         p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = NULL;
 249
 250         /* Set the new extradata */
 251         p_dec->fmt_out.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 252         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 253         memcpy( (uint8_t*)p_dec->fmt_out.p_extra, p_sys->p_sps->p_buffer, p_sys->p_sps->i_buffer);
 254         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);
 255         p_sys->b_header = VLC_TRUE;
 256
 257         /* Set callback */
 258         p_dec->pf_packetize = PacketizeAVC1;
 259     }
 260     else
 261     {
 262         /* This type of stream contains data with 3 of 4 byte startcodes
 263          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 264          * The fmt_out.p_extra should be the same */
 265
 266         /* Set callback */
 267         p_dec->pf_packetize = Packetize;
 268
 269         /* */
 270         if( p_dec->fmt_in.i_extra > 0 )
 271         {
 272             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 273             block_t *p_pic;
 274
 275             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 276                     p_dec->fmt_in.i_extra );
 277
 278             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 279             {
 280                 /* Should not occur because we should only receive SPS/PPS */
 281                 block_Release( p_pic );
 282             }
 283         }
 284     }
 285
 286     return VLC_SUCCESS;
 287 }
 288
 289 /*****************************************************************************
 290  * Close: clean up the packetizer
 291  *****************************************************************************/
 292 static void Close( vlc_object_t *p_this )
 293 {
 294     decoder_t *p_dec = (decoder_t*)p_this;
 295     decoder_sys_t *p_sys = p_dec->p_sys;
 296
 297     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 298     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 299     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 300     block_BytestreamRelease( &p_sys->bytestream );
 301     free( p_sys );
 302 }
 303
 304 /****************************************************************************
 305  * Packetize: the whole thing
 306  * Search for the startcodes 3 or more bytes
 307  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 308  ****************************************************************************/
 309 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 310 {
 311     decoder_sys_t *p_sys = p_dec->p_sys;
 312     block_t       *p_pic;
 313
 314     if( !pp_block || !*pp_block )
 315         return NULL;
 316
 317     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 318     {
 319         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 320         {
 321             p_sys->i_state = STATE_NOSYNC;
 322             block_BytestreamFlush( &p_sys->bytestream );
 323
 324             if( p_sys->p_frame )
 325                 block_ChainRelease( p_sys->p_frame );
 326             p_sys->p_frame = NULL;
 327             p_sys->slice.i_frame_type = 0;
 328             p_sys->b_slice = VLC_FALSE;
 329         }
 330         block_Release( *pp_block );
 331         return NULL;
 332     }
 333
 334     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 335
 336     for( ;; )
 337     {
 338         switch( p_sys->i_state )
 339         {
 340             case STATE_NOSYNC:
 341                 /* Skip until 3 byte startcode 0 0 1 */
 342                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 343                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 344                 {
 345                     p_sys->i_state = STATE_NEXT_SYNC;
 346                 }
 347
 348                 if( p_sys->i_offset )
 349                 {
 350                     /* skip the data */
 351                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 352                     p_sys->i_offset = 0;
 353                     block_BytestreamFlush( &p_sys->bytestream );
 354                 }
 355
 356                 if( p_sys->i_state != STATE_NEXT_SYNC )
 357                 {
 358                     /* Need more data */
 359                     return NULL;
 360                 }
 361
 362                 p_sys->i_offset = 1; /* To find next startcode */
 363
 364             case STATE_NEXT_SYNC:
 365                 /* Find the next 3 byte startcode 0 0 1*/
 366                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 367                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 368                 {
 369                     /* Need more data */
 370                     return NULL;
 371                 }
 372
 373                 /* Get the new fragment and set the pts/dts */
 374                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 375                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 376                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 377                 /* Force 4 byte startcode 0 0 0 1 */
 378                 p_pic->p_buffer[0] = 0;
 379
 380                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 381                                 p_pic->i_buffer-1 );
 382
 383                 /* Remove trailing 0 bytes */
 384                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 385                     p_pic->i_buffer--;
 386                 p_sys->i_offset = 0;
 387
 388                 /* Parse the NAL */
 389                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 390                 {
 391                     p_sys->i_state = STATE_NOSYNC;
 392                     break;
 393                 }
 394 #if 0
 395                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 396                          p_pic->i_pts, p_pic->i_dts );
 397 #endif
 398
 399                 /* So p_block doesn't get re-added several times */
 400                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 401
 402                 p_sys->i_state = STATE_NOSYNC;
 403
 404                 return p_pic;
 405         }
 406     }
 407 }
 408
 409 /****************************************************************************
 410  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 411  * Will always use 4 byte 0 0 0 1 startcodes
 412  * Will prepend a SPS and PPS before each keyframe
 413  ****************************************************************************/
 414 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 415 {
 416     decoder_sys_t *p_sys = p_dec->p_sys;
 417     block_t       *p_block;
 418     block_t       *p_ret = NULL;
 419     uint8_t       *p;
 420
 421     if( !pp_block || !*pp_block )
 422         return NULL;
 423     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 424     {
 425         block_Release( *pp_block );
 426         return NULL;
 427     }
 428
 429     p_block = *pp_block;
 430     *pp_block = NULL;
 431
 432     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 433     {
 434         block_t *p_pic;
 435         int i_size = 0;
 436         int i;
 437
 438         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 439         {
 440             i_size = (i_size << 8) | (*p++);
 441         }
 442
 443         if( i_size > 0 )
 444         {
 445             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 446
 447             p_part->i_dts = p_block->i_dts;
 448             p_part->i_pts = p_block->i_pts;
 449
 450             /* Parse the NAL */
 451             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 452             {
 453                 block_ChainAppend( &p_ret, p_pic );
 454             }
 455         }
 456         p += i_size;
 457     }
 458     block_Release( p_block );
 459
 460     return p_ret;
 461 }
 462
 463 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 464 {
 465     block_t *p_nal;
 466
 467     p_nal = block_New( p_dec, 4 + i_size );
 468
 469     /* Add start code */
 470     p_nal->p_buffer[0] = 0x00;
 471     p_nal->p_buffer[1] = 0x00;
 472     p_nal->p_buffer[2] = 0x00;
 473     p_nal->p_buffer[3] = 0x01;
 474
 475     /* Copy nalu */
 476     memcpy( &p_nal->p_buffer[4], p, i_size );
 477
 478     return p_nal;
 479 }
 480
 481 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 482                              uint8_t *src, int i_src )
 483 {
 484     uint8_t *end = &src[i_src];
 485     uint8_t *dst = malloc( i_src );
 486
 487     *pp_ret = dst;
 488
 489     while( src < end )
 490     {
 491         if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 492             src[2] == 0x03 )
 493         {
 494             *dst++ = 0x00;
 495             *dst++ = 0x00;
 496
 497             src += 3;
 498             continue;
 499         }
 500         *dst++ = *src++;
 501     }
 502
 503     *pi_ret = dst - *pp_ret;
 504 }
 505
 506 static inline int bs_read_ue( bs_t *s )
 507 {
 508     int i = 0;
 509
 510     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 511     {
 512         i++;
 513     }
 514     return( ( 1 << i) - 1 + bs_read( s, i ) );
 515 }
 516
 517 static inline int bs_read_se( bs_t *s )
 518 {
 519     int val = bs_read_ue( s );
 520
 521     return val&0x01 ? (val+1)/2 : -(val/2);
 522 }
 523
 524
 525 /*****************************************************************************
 526  * ParseNALBlock: parses annexB type NALs
 527  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 528  *****************************************************************************/
 529 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 530 {
 531     decoder_sys_t *p_sys = p_dec->p_sys;
 532     block_t *p_pic = NULL;
 533
 534     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 535     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 536
 537 #define OUTPUT \
 538     do {                                                      \
 539         if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I) \
 540             break;                                            \
 541                                                               \
 542         if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->p_sps && p_sys->p_pps && !p_sys->b_header ) \
 543         { \
 544             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 545             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 546             p_sps->i_dts = p_sys->p_frame->i_dts;           \
 547             p_sps->i_pts = p_sys->p_frame->i_pts;           \
 548             block_ChainAppend( &p_sps, p_pps );               \
 549             block_ChainAppend( &p_sps, p_sys->p_frame );      \
 550             p_sys->b_header = VLC_TRUE;                       \
 551             p_pic = block_ChainGather( p_sps );               \
 552         } else { \
 553             p_pic = block_ChainGather( p_sys->p_frame ); \
 554         } \
 555         p_pic->i_length = 0;    /* FIXME */                   \
 556         p_pic->i_flags |= p_sys->slice.i_frame_type;          \
 557             \
 558         p_sys->slice.i_frame_type = 0;                        \
 559         p_sys->p_frame = NULL;                                \
 560         p_sys->b_slice = VLC_FALSE;                           \
 561     } while(0)
 562
 563     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 564     {
 565         block_ChainRelease( p_sys->p_frame );
 566         msg_Warn( p_dec, "waiting for SPS/PPS" );
 567
 568         /* Reset context */
 569         p_sys->slice.i_frame_type = 0;
 570         p_sys->p_frame = NULL;
 571         p_sys->b_slice = VLC_FALSE;
 572     }
 573
 574     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 575         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 576     {
 577         p_sys->b_slice = VLC_TRUE;
 578         /* Fragment will be discarded later on */
 579     }
 580     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 581     {
 582         uint8_t *dec;
 583         int i_dec, i_first_mb, i_slice_type;
 584         slice_t slice;
 585         vlc_bool_t b_pic;
 586         bs_t s;
 587
 588         /* do not convert the whole frame */
 589         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 590                          __MIN( p_frag->i_buffer - 5, 60 ) );
 591         bs_init( &s, dec, i_dec );
 592
 593         /* first_mb_in_slice */
 594         i_first_mb = bs_read_ue( &s );
 595
 596         /* slice_type */
 597         switch( (i_slice_type = bs_read_ue( &s )) )
 598         {
 599         case 0: case 5:
 600             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 601             break;
 602         case 1: case 6:
 603             slice.i_frame_type = BLOCK_FLAG_TYPE_B;
 604             break;
 605         case 2: case 7:
 606             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 607             break;
 608         case 3: case 8: /* SP */
 609             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 610             break;
 611         case 4: case 9:
 612             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 613             break;
 614         default:
 615             slice.i_frame_type = 0;
 616             break;
 617         }
 618
 619         /* */
 620         slice.i_nal_type = i_nal_type;
 621         slice.i_nal_ref_idc = i_nal_ref_idc;
 622
 623         slice.i_pic_parameter_set_id = bs_read_ue( &s );
 624         slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 625
 626         slice.i_field_pic_flag = 0;
 627         slice.i_bottom_field_flag = -1;
 628         if( !p_sys->b_frame_mbs_only )
 629         {
 630             /* field_pic_flag */
 631             slice.i_field_pic_flag = bs_read( &s, 1 );
 632             if( slice.i_field_pic_flag )
 633                 slice.i_bottom_field_flag = bs_read( &s, 1 );
 634         }
 635
 636         slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
 637         if( slice.i_nal_type == NAL_SLICE_IDR )
 638             slice.i_idr_pic_id = bs_read_ue( &s );
 639
 640         slice.i_pic_order_cnt_lsb = -1;
 641         slice.i_delta_pic_order_cnt_bottom = -1;
 642         slice.i_delta_pic_order_cnt0 = 0;
 643         slice.i_delta_pic_order_cnt1 = 0;
 644         if( p_sys->i_pic_order_cnt_type == 0 )
 645         {
 646             slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
 647             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 648                 slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
 649         }
 650         else if( p_sys->i_pic_order_cnt_type == 1 && !p_sys->i_delta_pic_order_always_zero_flag )
 651         {
 652             slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
 653             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 654                 slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
 655         }
 656
 657         /* Detection of the first VCL NAL unit of a primary coded picture
 658          * (cf. 7.4.1.2.4) */
 659         b_pic = VLC_FALSE;
 660         if( slice.i_frame_num != p_sys->slice.i_frame_num ||
 661             slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
 662             slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
 663             slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
 664             b_pic = VLC_TRUE;
 665         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 )
 666             b_pic = VLC_TRUE;
 667         if( p_sys->i_pic_order_cnt_type == 0 &&
 668             ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
 669               slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
 670             b_pic = VLC_TRUE;
 671         else if( p_sys->i_pic_order_cnt_type == 1 &&
 672                  ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
 673                    slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
 674             b_pic = VLC_TRUE;
 675         if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
 676             ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
 677                 b_pic = VLC_TRUE;
 678
 679         /* */
 680         p_sys->slice = slice;
 681
 682         if( b_pic && p_sys->b_slice )
 683             OUTPUT;
 684
 685         p_sys->b_slice = VLC_TRUE;
 686
 687         free( dec );
 688     }
 689     else if( i_nal_type == NAL_SPS )
 690     {
 691         uint8_t *dec;
 692         int     i_dec;
 693         bs_t s;
 694         int i_tmp;
 695
 696         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 697
 698         p_sys->b_sps = VLC_TRUE;
 699
 700         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 701                          p_frag->i_buffer - 5 );
 702
 703         bs_init( &s, dec, i_dec );
 704         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 705         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 706         /* sps id */
 707         bs_read_ue( &s );
 708         /* Skip i_log2_max_frame_num */
 709         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 710         if( p_sys->i_log2_max_frame_num > 12)
 711             p_sys->i_log2_max_frame_num = 12;
 712         /* Read poc_type */
 713         p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 714         if( p_sys->i_pic_order_cnt_type == 0 )
 715         {
 716             /* skip i_log2_max_poc_lsb */
 717             p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 718             if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 719                 p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 720         }
 721         else if( p_sys->i_pic_order_cnt_type == 1 )
 722         {
 723             int i_cycle;
 724             /* skip b_delta_pic_order_always_zero */
 725             p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 726             /* skip i_offset_for_non_ref_pic */
 727             bs_read_se( &s );
 728             /* skip i_offset_for_top_to_bottom_field */
 729             bs_read_se( &s );
 730             /* read i_num_ref_frames_in_poc_cycle */
 731             i_cycle = bs_read_ue( &s );
 732             if( i_cycle > 256 ) i_cycle = 256;
 733             while( i_cycle > 0 )
 734             {
 735                 /* skip i_offset_for_ref_frame */
 736                 bs_read_se(&s );
 737             }
 738         }
 739         /* i_num_ref_frames */
 740         bs_read_ue( &s );
 741         /* b_gaps_in_frame_num_value_allowed */
 742         bs_skip( &s, 1 );
 743
 744         /* Read size */
 745         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 746         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 747
 748         /* b_frame_mbs_only */
 749         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 750         if( p_sys->b_frame_mbs_only == 0 )
 751         {
 752             bs_skip( &s, 1 );
 753         }
 754         /* b_direct8x8_inference */
 755         bs_skip( &s, 1 );
 756
 757         /* crop */
 758         i_tmp = bs_read( &s, 1 );
 759         if( i_tmp )
 760         {
 761             /* left */
 762             bs_read_ue( &s );
 763             /* right */
 764             bs_read_ue( &s );
 765             /* top */
 766             bs_read_ue( &s );
 767             /* bottom */
 768             bs_read_ue( &s );
 769         }
 770
 771         /* vui */
 772         i_tmp = bs_read( &s, 1 );
 773         if( i_tmp )
 774         {
 775             /* read the aspect ratio part if any FIXME check it */
 776             i_tmp = bs_read( &s, 1 );
 777             if( i_tmp )
 778             {
 779                 static const struct { int w, h; } sar[14] =
 780                 {
 781                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 782                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 783                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 784                     { 64, 33 }, { 160,99 },
 785                 };
 786                 int i_sar = bs_read( &s, 8 );
 787                 int w, h;
 788
 789                 if( i_sar < 14 )
 790                 {
 791                     w = sar[i_sar].w;
 792                     h = sar[i_sar].h;
 793                 }
 794                 else
 795                 {
 796                     w = bs_read( &s, 16 );
 797                     h = bs_read( &s, 16 );
 798                 }
 799                 if( h != 0 )
 800                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 801                         h * p_dec->fmt_out.video.i_width /
 802                         p_dec->fmt_out.video.i_height;
 803                 else
 804                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 805             }
 806         }
 807
 808         free( dec );
 809
 810         if( p_sys->b_slice ) OUTPUT;
 811
 812         /* We have a new SPS */
 813         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 814         p_sys->p_sps = p_frag;
 815
 816         /* Do not append the SPS because we will insert it on keyframes */
 817         return p_pic;
 818     }
 819     else if( i_nal_type == NAL_PPS )
 820     {
 821         bs_t s;
 822
 823         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 824         bs_read_ue( &s ); // pps id
 825         bs_read_ue( &s ); // sps id
 826         bs_skip( &s, 1 ); // entropy coding mode flag
 827         p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 828
 829         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 830         p_sys->b_pps = VLC_TRUE;
 831
 832         /* TODO */
 833
 834         if( p_sys->b_slice ) OUTPUT;
 835
 836         /* We have a new PPS */
 837         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 838         p_sys->p_pps = p_frag;
 839
 840         /* Do not append the PPS because we will insert it on keyframes */
 841         return p_pic;
 842     }
 843     else if( i_nal_type == NAL_AU_DELIMITER ||
 844              i_nal_type == NAL_SEI ||
 845              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 846     {
 847         if( p_sys->b_slice ) OUTPUT;
 848     }
 849
 850 #undef OUTPUT
 851
 852     /* Append the block */
 853     block_ChainAppend( &p_sys->p_frame, p_frag );
 854
 855     return p_pic;
 856 }