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.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 251         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 252         if( p_dec->fmt_out.p_extra )
 253         {
 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         else p_dec->fmt_out.i_extra = 0;
 259
 260         /* Set callback */
 261         p_dec->pf_packetize = PacketizeAVC1;
 262     }
 263     else
 264     {
 265         /* This type of stream contains data with 3 of 4 byte startcodes
 266          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 267          * The fmt_out.p_extra should be the same */
 268
 269         /* Set callback */
 270         p_dec->pf_packetize = Packetize;
 271
 272         /* */
 273         if( p_dec->fmt_in.i_extra > 0 )
 274         {
 275             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 276             block_t *p_pic;
 277
 278             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 279                     p_dec->fmt_in.i_extra );
 280
 281             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 282             {
 283                 /* Should not occur because we should only receive SPS/PPS */
 284                 block_Release( p_pic );
 285             }
 286         }
 287     }
 288
 289     return VLC_SUCCESS;
 290 }
 291
 292 /*****************************************************************************
 293  * Close: clean up the packetizer
 294  *****************************************************************************/
 295 static void Close( vlc_object_t *p_this )
 296 {
 297     decoder_t *p_dec = (decoder_t*)p_this;
 298     decoder_sys_t *p_sys = p_dec->p_sys;
 299
 300     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 301     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 302     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 303     block_BytestreamRelease( &p_sys->bytestream );
 304     free( p_sys );
 305 }
 306
 307 /****************************************************************************
 308  * Packetize: the whole thing
 309  * Search for the startcodes 3 or more bytes
 310  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 311  ****************************************************************************/
 312 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 313 {
 314     decoder_sys_t *p_sys = p_dec->p_sys;
 315     block_t       *p_pic;
 316
 317     if( !pp_block || !*pp_block )
 318         return NULL;
 319
 320     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 321     {
 322         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 323         {
 324             p_sys->i_state = STATE_NOSYNC;
 325             block_BytestreamFlush( &p_sys->bytestream );
 326
 327             if( p_sys->p_frame )
 328                 block_ChainRelease( p_sys->p_frame );
 329             p_sys->p_frame = NULL;
 330             p_sys->slice.i_frame_type = 0;
 331             p_sys->b_slice = VLC_FALSE;
 332         }
 333         block_Release( *pp_block );
 334         return NULL;
 335     }
 336
 337     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 338
 339     for( ;; )
 340     {
 341         switch( p_sys->i_state )
 342         {
 343             case STATE_NOSYNC:
 344                 /* Skip until 3 byte startcode 0 0 1 */
 345                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 346                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 347                 {
 348                     p_sys->i_state = STATE_NEXT_SYNC;
 349                 }
 350
 351                 if( p_sys->i_offset )
 352                 {
 353                     /* skip the data */
 354                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 355                     p_sys->i_offset = 0;
 356                     block_BytestreamFlush( &p_sys->bytestream );
 357                 }
 358
 359                 if( p_sys->i_state != STATE_NEXT_SYNC )
 360                 {
 361                     /* Need more data */
 362                     return NULL;
 363                 }
 364
 365                 p_sys->i_offset = 1; /* To find next startcode */
 366
 367             case STATE_NEXT_SYNC:
 368                 /* Find the next 3 byte startcode 0 0 1*/
 369                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 370                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 371                 {
 372                     /* Need more data */
 373                     return NULL;
 374                 }
 375
 376                 /* Get the new fragment and set the pts/dts */
 377                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 378                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 379                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 380                 /* Force 4 byte startcode 0 0 0 1 */
 381                 p_pic->p_buffer[0] = 0;
 382
 383                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 384                                 p_pic->i_buffer-1 );
 385
 386                 /* Remove trailing 0 bytes */
 387                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 388                     p_pic->i_buffer--;
 389                 p_sys->i_offset = 0;
 390
 391                 /* Parse the NAL */
 392                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 393                 {
 394                     p_sys->i_state = STATE_NOSYNC;
 395                     break;
 396                 }
 397 #if 0
 398                 msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
 399                          p_pic->i_pts, p_pic->i_dts );
 400 #endif
 401
 402                 /* So p_block doesn't get re-added several times */
 403                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 404
 405                 p_sys->i_state = STATE_NOSYNC;
 406
 407                 return p_pic;
 408         }
 409     }
 410 }
 411
 412 /****************************************************************************
 413  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 414  * Will always use 4 byte 0 0 0 1 startcodes
 415  * Will prepend a SPS and PPS before each keyframe
 416  ****************************************************************************/
 417 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 418 {
 419     decoder_sys_t *p_sys = p_dec->p_sys;
 420     block_t       *p_block;
 421     block_t       *p_ret = NULL;
 422     uint8_t       *p;
 423
 424     if( !pp_block || !*pp_block )
 425         return NULL;
 426     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 427     {
 428         block_Release( *pp_block );
 429         return NULL;
 430     }
 431
 432     p_block = *pp_block;
 433     *pp_block = NULL;
 434
 435     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 436     {
 437         block_t *p_pic;
 438         int i_size = 0;
 439         int i;
 440
 441         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 442         {
 443             i_size = (i_size << 8) | (*p++);
 444         }
 445
 446         if( i_size > 0 )
 447         {
 448             block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 449
 450             p_part->i_dts = p_block->i_dts;
 451             p_part->i_pts = p_block->i_pts;
 452
 453             /* Parse the NAL */
 454             if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 455             {
 456                 block_ChainAppend( &p_ret, p_pic );
 457             }
 458         }
 459         p += i_size;
 460     }
 461     block_Release( p_block );
 462
 463     return p_ret;
 464 }
 465
 466 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 467 {
 468     block_t *p_nal;
 469
 470     p_nal = block_New( p_dec, 4 + i_size );
 471
 472     /* Add start code */
 473     p_nal->p_buffer[0] = 0x00;
 474     p_nal->p_buffer[1] = 0x00;
 475     p_nal->p_buffer[2] = 0x00;
 476     p_nal->p_buffer[3] = 0x01;
 477
 478     /* Copy nalu */
 479     memcpy( &p_nal->p_buffer[4], p, i_size );
 480
 481     return p_nal;
 482 }
 483
 484 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 485                              uint8_t *src, int i_src )
 486 {
 487     uint8_t *end = &src[i_src];
 488     uint8_t *dst = malloc( i_src );
 489
 490     *pp_ret = dst;
 491
 492     if( dst )
 493     {
 494         while( src < end )
 495         {
 496             if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 497                 src[2] == 0x03 )
 498             {
 499                 *dst++ = 0x00;
 500                 *dst++ = 0x00;
 501
 502                 src += 3;
 503                 continue;
 504             }
 505             *dst++ = *src++;
 506         }
 507     }
 508     *pi_ret = dst - *pp_ret;
 509 }
 510
 511 static inline int bs_read_ue( bs_t *s )
 512 {
 513     int i = 0;
 514
 515     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 516     {
 517         i++;
 518     }
 519     return( ( 1 << i) - 1 + bs_read( s, i ) );
 520 }
 521
 522 static inline int bs_read_se( bs_t *s )
 523 {
 524     int val = bs_read_ue( s );
 525
 526     return val&0x01 ? (val+1)/2 : -(val/2);
 527 }
 528
 529 /*****************************************************************************
 530  * ParseNALBlock: parses annexB type NALs
 531  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 532  *****************************************************************************/
 533 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 534 {
 535     decoder_sys_t *p_sys = p_dec->p_sys;
 536     block_t *p_pic = NULL;
 537
 538     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 539     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 540
 541 #define OUTPUT \
 542     do {                                                      \
 543         if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I) \
 544             break;                                            \
 545                                                               \
 546         if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->p_sps && p_sys->p_pps ) \
 547         { \
 548             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 549             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 550             p_sps->i_dts = p_sys->p_frame->i_dts;           \
 551             p_sps->i_pts = p_sys->p_frame->i_pts;           \
 552             block_ChainAppend( &p_sps, p_pps );               \
 553             block_ChainAppend( &p_sps, p_sys->p_frame );      \
 554             p_sys->b_header = VLC_TRUE;                       \
 555             p_pic = block_ChainGather( p_sps );               \
 556         } else { \
 557             p_pic = block_ChainGather( p_sys->p_frame ); \
 558         } \
 559         p_pic->i_length = 0;    /* FIXME */                   \
 560         p_pic->i_flags |= p_sys->slice.i_frame_type;          \
 561             \
 562         p_sys->slice.i_frame_type = 0;                        \
 563         p_sys->p_frame = NULL;                                \
 564         p_sys->b_slice = VLC_FALSE;                           \
 565     } while(0)
 566
 567     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 568     {
 569         block_ChainRelease( p_sys->p_frame );
 570         msg_Warn( p_dec, "waiting for SPS/PPS" );
 571
 572         /* Reset context */
 573         p_sys->slice.i_frame_type = 0;
 574         p_sys->p_frame = NULL;
 575         p_sys->b_slice = VLC_FALSE;
 576     }
 577
 578     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 579         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 580     {
 581         p_sys->b_slice = VLC_TRUE;
 582         /* Fragment will be discarded later on */
 583     }
 584     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 585     {
 586         uint8_t *dec = NULL;
 587         int i_dec = 0, i_first_mb, i_slice_type;
 588         slice_t slice;
 589         vlc_bool_t b_pic;
 590         bs_t s;
 591
 592         /* do not convert the whole frame */
 593         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 594                          __MIN( p_frag->i_buffer - 5, 60 ) );
 595         bs_init( &s, dec, i_dec );
 596
 597         /* first_mb_in_slice */
 598         i_first_mb = bs_read_ue( &s );
 599
 600         /* slice_type */
 601         switch( (i_slice_type = bs_read_ue( &s )) )
 602         {
 603         case 0: case 5:
 604             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 605             break;
 606         case 1: case 6:
 607             slice.i_frame_type = BLOCK_FLAG_TYPE_B;
 608             break;
 609         case 2: case 7:
 610             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 611             break;
 612         case 3: case 8: /* SP */
 613             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 614             break;
 615         case 4: case 9:
 616             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 617             break;
 618         default:
 619             slice.i_frame_type = 0;
 620             break;
 621         }
 622
 623         /* */
 624         slice.i_nal_type = i_nal_type;
 625         slice.i_nal_ref_idc = i_nal_ref_idc;
 626
 627         slice.i_pic_parameter_set_id = bs_read_ue( &s );
 628         slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 629
 630         slice.i_field_pic_flag = 0;
 631         slice.i_bottom_field_flag = -1;
 632         if( !p_sys->b_frame_mbs_only )
 633         {
 634             /* field_pic_flag */
 635             slice.i_field_pic_flag = bs_read( &s, 1 );
 636             if( slice.i_field_pic_flag )
 637                 slice.i_bottom_field_flag = bs_read( &s, 1 );
 638         }
 639
 640         slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
 641         if( slice.i_nal_type == NAL_SLICE_IDR )
 642             slice.i_idr_pic_id = bs_read_ue( &s );
 643
 644         slice.i_pic_order_cnt_lsb = -1;
 645         slice.i_delta_pic_order_cnt_bottom = -1;
 646         slice.i_delta_pic_order_cnt0 = 0;
 647         slice.i_delta_pic_order_cnt1 = 0;
 648         if( p_sys->i_pic_order_cnt_type == 0 )
 649         {
 650             slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
 651             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 652                 slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
 653         }
 654         else if( (p_sys->i_pic_order_cnt_type == 1) &&
 655                  (!p_sys->i_delta_pic_order_always_zero_flag) )
 656         {
 657             slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
 658             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 659                 slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
 660         }
 661
 662         /* Detection of the first VCL NAL unit of a primary coded picture
 663          * (cf. 7.4.1.2.4) */
 664         b_pic = VLC_FALSE;
 665         if( slice.i_frame_num != p_sys->slice.i_frame_num ||
 666             slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
 667             slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
 668             slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
 669             b_pic = VLC_TRUE;
 670         if( (slice.i_bottom_field_flag != -1) &&
 671             (p_sys->slice.i_bottom_field_flag != -1) &&
 672             (slice.i_bottom_field_flag != p_sys->slice.i_bottom_field_flag) )
 673             b_pic = VLC_TRUE;
 674         if( p_sys->i_pic_order_cnt_type == 0 &&
 675             ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
 676               slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
 677             b_pic = VLC_TRUE;
 678         else if( p_sys->i_pic_order_cnt_type == 1 &&
 679                  ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
 680                    slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
 681             b_pic = VLC_TRUE;
 682         if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
 683             ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
 684                 b_pic = VLC_TRUE;
 685
 686         /* */
 687         p_sys->slice = slice;
 688
 689         if( b_pic && p_sys->b_slice )
 690             OUTPUT;
 691
 692         p_sys->b_slice = VLC_TRUE;
 693
 694         free( dec );
 695     }
 696     else if( i_nal_type == NAL_SPS )
 697     {
 698         uint8_t *dec = NULL;
 699         int     i_dec = 0;
 700         bs_t s;
 701         int i_tmp;
 702
 703         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 704
 705         p_sys->b_sps = VLC_TRUE;
 706
 707         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 708                          p_frag->i_buffer - 5 );
 709
 710         bs_init( &s, dec, i_dec );
 711         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 712         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 713         /* sps id */
 714         bs_read_ue( &s );
 715         /* Skip i_log2_max_frame_num */
 716         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 717         if( p_sys->i_log2_max_frame_num > 12)
 718             p_sys->i_log2_max_frame_num = 12;
 719         /* Read poc_type */
 720         p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 721         if( p_sys->i_pic_order_cnt_type == 0 )
 722         {
 723             /* skip i_log2_max_poc_lsb */
 724             p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 725             if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 726                 p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 727         }
 728         else if( p_sys->i_pic_order_cnt_type == 1 )
 729         {
 730             int i_cycle;
 731             /* skip b_delta_pic_order_always_zero */
 732             p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 733             /* skip i_offset_for_non_ref_pic */
 734             bs_read_se( &s );
 735             /* skip i_offset_for_top_to_bottom_field */
 736             bs_read_se( &s );
 737             /* read i_num_ref_frames_in_poc_cycle */
 738             i_cycle = bs_read_ue( &s );
 739             if( i_cycle > 256 ) i_cycle = 256;
 740             while( i_cycle > 0 )
 741             {
 742                 /* skip i_offset_for_ref_frame */
 743                 bs_read_se(&s );
 744             }
 745         }
 746         /* i_num_ref_frames */
 747         bs_read_ue( &s );
 748         /* b_gaps_in_frame_num_value_allowed */
 749         bs_skip( &s, 1 );
 750
 751         /* Read size */
 752         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 753         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 754
 755         /* b_frame_mbs_only */
 756         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 757         if( p_sys->b_frame_mbs_only == 0 )
 758         {
 759             bs_skip( &s, 1 );
 760         }
 761         /* b_direct8x8_inference */
 762         bs_skip( &s, 1 );
 763
 764         /* crop */
 765         i_tmp = bs_read( &s, 1 );
 766         if( i_tmp )
 767         {
 768             /* left */
 769             bs_read_ue( &s );
 770             /* right */
 771             bs_read_ue( &s );
 772             /* top */
 773             bs_read_ue( &s );
 774             /* bottom */
 775             bs_read_ue( &s );
 776         }
 777
 778         /* vui */
 779         i_tmp = bs_read( &s, 1 );
 780         if( i_tmp )
 781         {
 782             /* read the aspect ratio part if any FIXME check it */
 783             i_tmp = bs_read( &s, 1 );
 784             if( i_tmp )
 785             {
 786                 static const struct { int w, h; } sar[14] =
 787                 {
 788                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 789                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 790                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 791                     { 64, 33 }, { 160,99 },
 792                 };
 793                 int i_sar = bs_read( &s, 8 );
 794                 int w, h;
 795
 796                 if( i_sar < 14 )
 797                 {
 798                     w = sar[i_sar].w;
 799                     h = sar[i_sar].h;
 800                 }
 801                 else
 802                 {
 803                     w = bs_read( &s, 16 );
 804                     h = bs_read( &s, 16 );
 805                 }
 806                 if( h != 0 )
 807                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 808                         h * p_dec->fmt_out.video.i_width /
 809                         p_dec->fmt_out.video.i_height;
 810                 else
 811                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 812             }
 813         }
 814
 815         free( dec );
 816
 817         if( p_sys->b_slice ) OUTPUT;
 818
 819         /* We have a new SPS */
 820         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 821         p_sys->p_sps = p_frag;
 822
 823         /* Do not append the SPS because we will insert it on keyframes */
 824         return p_pic;
 825     }
 826     else if( i_nal_type == NAL_PPS )
 827     {
 828         bs_t s;
 829
 830         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 831         bs_read_ue( &s ); // pps id
 832         bs_read_ue( &s ); // sps id
 833         bs_skip( &s, 1 ); // entropy coding mode flag
 834         p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 835
 836         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 837         p_sys->b_pps = VLC_TRUE;
 838
 839         /* TODO */
 840
 841         if( p_sys->b_slice ) OUTPUT;
 842
 843         /* We have a new PPS */
 844         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 845         p_sys->p_pps = p_frag;
 846
 847         /* Do not append the PPS because we will insert it on keyframes */
 848         return p_pic;
 849     }
 850     else if( i_nal_type == NAL_AU_DELIMITER ||
 851              i_nal_type == NAL_SEI ||
 852              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 853     {
 854         if( p_sys->b_slice ) OUTPUT;
 855     }
 856
 857 #undef OUTPUT
 858
 859     /* Append the block */
 860     block_ChainAppend( &p_sys->p_frame, p_frag );
 861
 862     return p_pic;
 863 }