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 #ifdef HAVE_CONFIG_H
  32 # include "config.h"
  33 #endif
  34
  35 #include <vlc/vlc.h>
  36 #include <vlc_plugin.h>
  37 #include <vlc_sout.h>
  38 #include <vlc_codec.h>
  39 #include <vlc_block.h>
  40
  41 #include "vlc_block_helper.h"
  42 #include "vlc_bits.h"
  43
  44 /*****************************************************************************
  45  * Module descriptor
  46  *****************************************************************************/
  47 static int  Open ( vlc_object_t * );
  48 static void Close( vlc_object_t * );
  49
  50 vlc_module_begin();
  51     set_category( CAT_SOUT );
  52     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  53     set_description( _("H.264 video packetizer") );
  54     set_capability( "packetizer", 50 );
  55     set_callbacks( Open, Close );
  56 vlc_module_end();
  57
  58
  59 /****************************************************************************
  60  * Local prototypes
  61  ****************************************************************************/
  62 static block_t *Packetize( decoder_t *, block_t ** );
  63 static block_t *PacketizeAVC1( decoder_t *, block_t ** );
  64
  65 typedef struct
  66 {
  67     int i_nal_type;
  68     int i_nal_ref_idc;
  69
  70     int i_frame_type;
  71     int i_pic_parameter_set_id;
  72     int i_frame_num;
  73
  74     int i_field_pic_flag;
  75     int i_bottom_field_flag;
  76
  77     int i_idr_pic_id;
  78
  79     int i_pic_order_cnt_lsb;
  80     int i_delta_pic_order_cnt_bottom;
  81
  82     int i_delta_pic_order_cnt0;
  83     int i_delta_pic_order_cnt1;
  84 } slice_t;
  85
  86 struct decoder_sys_t
  87 {
  88     block_bytestream_t bytestream;
  89
  90     int     i_state;
  91     size_t  i_offset;
  92     uint8_t startcode[4];
  93
  94     bool b_slice;
  95     block_t    *p_frame;
  96
  97     bool   b_sps;
  98     bool   b_pps;
  99     bool   b_header;
 100
 101     /* avcC data */
 102     int i_avcC_length_size;
 103     block_t *p_sps;
 104     block_t *p_pps;
 105
 106     /* Useful values of the Sequence Parameter Set */
 107     int i_log2_max_frame_num;
 108     int b_frame_mbs_only;
 109     int i_pic_order_cnt_type;
 110     int i_delta_pic_order_always_zero_flag;
 111     int i_log2_max_pic_order_cnt_lsb;
 112
 113     /* Value from Picture Parameter Set */
 114     int i_pic_order_present_flag;
 115
 116     /* Useful values of the Slice Header */
 117     slice_t slice;
 118 };
 119
 120 enum
 121 {
 122     STATE_NOSYNC,
 123     STATE_NEXT_SYNC,
 124 };
 125
 126 enum nal_unit_type_e
 127 {
 128     NAL_UNKNOWN = 0,
 129     NAL_SLICE   = 1,
 130     NAL_SLICE_DPA   = 2,
 131     NAL_SLICE_DPB   = 3,
 132     NAL_SLICE_DPC   = 4,
 133     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 134     NAL_SEI         = 6,    /* ref_idc == 0 */
 135     NAL_SPS         = 7,
 136     NAL_PPS         = 8,
 137     NAL_AU_DELIMITER= 9
 138     /* ref_idc == 0 for 6,9,10,11,12 */
 139 };
 140
 141 enum nal_priority_e
 142 {
 143     NAL_PRIORITY_DISPOSABLE = 0,
 144     NAL_PRIORITY_LOW        = 1,
 145     NAL_PRIORITY_HIGH       = 2,
 146     NAL_PRIORITY_HIGHEST    = 3,
 147 };
 148
 149 static block_t *ParseNALBlock( decoder_t *, block_t * );
 150
 151 static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
 152
 153 /*****************************************************************************
 154  * Open: probe the packetizer and return score
 155  * When opening after demux, the packetizer is only loaded AFTER the decoder
 156  * That means that what you set in fmt_out is ignored by the decoder in this special case
 157  *****************************************************************************/
 158 static int Open( vlc_object_t *p_this )
 159 {
 160     decoder_t     *p_dec = (decoder_t*)p_this;
 161     decoder_sys_t *p_sys;
 162
 163     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 164         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 165         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 166         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 167         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 168         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 169           p_dec->fmt_in.i_extra < 7 ) )
 170     {
 171         return VLC_EGENERIC;
 172     }
 173
 174     /* Allocate the memory needed to store the decoder's structure */
 175     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 176     {
 177         msg_Err( p_dec, "out of memory" );
 178         return VLC_EGENERIC;
 179     }
 180     p_sys->i_state = STATE_NOSYNC;
 181     p_sys->i_offset = 0;
 182     p_sys->startcode[0] = 0;
 183     p_sys->startcode[1] = 0;
 184     p_sys->startcode[2] = 0;
 185     p_sys->startcode[3] = 1;
 186     p_sys->bytestream = block_BytestreamInit();
 187     p_sys->b_slice = false;
 188     p_sys->p_frame = NULL;
 189     p_sys->b_sps   = false;
 190     p_sys->b_pps   = false;
 191     p_sys->p_sps   = 0;
 192     p_sys->p_pps   = 0;
 193     p_sys->b_header= false;
 194
 195     p_sys->slice.i_nal_type = -1;
 196     p_sys->slice.i_nal_ref_idc = -1;
 197     p_sys->slice.i_idr_pic_id = -1;
 198     p_sys->slice.i_frame_num = -1;
 199     p_sys->slice.i_frame_type = 0;
 200     p_sys->slice.i_pic_parameter_set_id = -1;
 201     p_sys->slice.i_field_pic_flag = 0;
 202     p_sys->slice.i_bottom_field_flag = -1;
 203     p_sys->slice.i_pic_order_cnt_lsb = -1;
 204     p_sys->slice.i_delta_pic_order_cnt_bottom = -1;
 205
 206     /* Setup properties */
 207     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 208     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 209
 210     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 211     {
 212         /* This type of stream is produced by mp4 and matroska
 213          * when we want to store it in another streamformat, you need to convert
 214          * The fmt_in.p_extra should ALWAYS contain the avcC
 215          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 216         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 217         int i_sps, i_pps;
 218         int i;
 219
 220         /* Parse avcC */
 221         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 222
 223         /* Read SPS */
 224         i_sps = (*p++)&0x1f;
 225         for( i = 0; i < i_sps; i++ )
 226         {
 227             uint16_t i_length = GetWBE( p ); p += 2;
 228             if( i_length >
 229                 (uint8_t*)p_dec->fmt_in.p_extra + p_dec->fmt_in.i_extra - p )
 230             {
 231                 return VLC_EGENERIC;
 232             }
 233             block_t *p_sps = nal_get_annexeb( p_dec, p, i_length );
 234             if( !p_sps )
 235                 return VLC_EGENERIC;
 236             p_sys->p_sps = block_Duplicate( p_sps );
 237             p_sps->i_pts = p_sps->i_dts = mdate();
 238             ParseNALBlock( p_dec, p_sps );
 239             p += i_length;
 240         }
 241         /* Read PPS */
 242         i_pps = *p++;
 243         for( i = 0; i < i_pps; i++ )
 244         {
 245             uint16_t i_length = GetWBE( p ); p += 2;
 246             if( i_length >
 247                 (uint8_t*)p_dec->fmt_in.p_extra + p_dec->fmt_in.i_extra - p )
 248             {
 249                 return VLC_EGENERIC;
 250             }
 251             block_t *p_pps = nal_get_annexeb( p_dec, p, i_length );
 252             if( !p_pps )
 253                 return VLC_EGENERIC;
 254             p_sys->p_pps = block_Duplicate( p_pps );
 255             p_pps->i_pts = p_pps->i_dts = mdate();
 256             ParseNALBlock( p_dec, p_pps );
 257             p += i_length;
 258         }
 259         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 260                  p_sys->i_avcC_length_size, i_sps, i_pps );
 261
 262         /* FIXME: FFMPEG isn't happy at all if you leave this */
 263         if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
 264         p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = NULL;
 265
 266         /* Set the new extradata */
 267         p_dec->fmt_out.i_extra = p_sys->p_pps->i_buffer + p_sys->p_sps->i_buffer;
 268         p_dec->fmt_out.p_extra = (uint8_t*)malloc( p_dec->fmt_out.i_extra );
 269         if( p_dec->fmt_out.p_extra )
 270         {
 271             memcpy( (uint8_t*)p_dec->fmt_out.p_extra, p_sys->p_sps->p_buffer, p_sys->p_sps->i_buffer);
 272             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);
 273             p_sys->b_header = true;
 274         }
 275         else p_dec->fmt_out.i_extra = 0;
 276
 277         /* Set callback */
 278         p_dec->pf_packetize = PacketizeAVC1;
 279     }
 280     else
 281     {
 282         /* This type of stream contains data with 3 of 4 byte startcodes
 283          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 284          * The fmt_out.p_extra should be the same */
 285
 286         /* Set callback */
 287         p_dec->pf_packetize = Packetize;
 288
 289         /* */
 290         if( p_dec->fmt_in.i_extra > 0 )
 291         {
 292             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 293             block_t *p_pic;
 294
 295             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 296                     p_dec->fmt_in.i_extra );
 297
 298             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 299             {
 300                 /* Should not occur because we should only receive SPS/PPS */
 301                 block_Release( p_pic );
 302             }
 303         }
 304     }
 305
 306     return VLC_SUCCESS;
 307 }
 308
 309 /*****************************************************************************
 310  * Close: clean up the packetizer
 311  *****************************************************************************/
 312 static void Close( vlc_object_t *p_this )
 313 {
 314     decoder_t *p_dec = (decoder_t*)p_this;
 315     decoder_sys_t *p_sys = p_dec->p_sys;
 316
 317     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 318     if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 319     if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 320     block_BytestreamRelease( &p_sys->bytestream );
 321     free( p_sys );
 322 }
 323
 324 /****************************************************************************
 325  * Packetize: the whole thing
 326  * Search for the startcodes 3 or more bytes
 327  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 328  ****************************************************************************/
 329 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 330 {
 331     decoder_sys_t *p_sys = p_dec->p_sys;
 332     block_t       *p_pic;
 333
 334     if( !pp_block || !*pp_block )
 335         return NULL;
 336
 337     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 338     {
 339         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 340         {
 341             p_sys->i_state = STATE_NOSYNC;
 342             block_BytestreamFlush( &p_sys->bytestream );
 343
 344             if( p_sys->p_frame )
 345                 block_ChainRelease( p_sys->p_frame );
 346             p_sys->p_frame = NULL;
 347             p_sys->slice.i_frame_type = 0;
 348             p_sys->b_slice = false;
 349         }
 350         block_Release( *pp_block );
 351         return NULL;
 352     }
 353
 354     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 355
 356     for( ;; )
 357     {
 358         switch( p_sys->i_state )
 359         {
 360             case STATE_NOSYNC:
 361                 /* Skip until 3 byte startcode 0 0 1 */
 362                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 363                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 364                 {
 365                     p_sys->i_state = STATE_NEXT_SYNC;
 366                 }
 367
 368                 if( p_sys->i_offset )
 369                 {
 370                     /* skip the data */
 371                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 372                     p_sys->i_offset = 0;
 373                     block_BytestreamFlush( &p_sys->bytestream );
 374                 }
 375
 376                 if( p_sys->i_state != STATE_NEXT_SYNC )
 377                 {
 378                     /* Need more data */
 379                     return NULL;
 380                 }
 381
 382                 p_sys->i_offset = 1; /* To find next startcode */
 383
 384             case STATE_NEXT_SYNC:
 385                 /* Find the next 3 byte startcode 0 0 1*/
 386                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 387                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 388                 {
 389                     /* Need more data */
 390                     return NULL;
 391                 }
 392
 393                 /* Get the new fragment and set the pts/dts */
 394                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 395                 p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
 396                 p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
 397                 /* Force 4 byte startcode 0 0 0 1 */
 398                 p_pic->p_buffer[0] = 0;
 399
 400                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 401                                 p_pic->i_buffer-1 );
 402
 403                 /* Remove trailing 0 bytes */
 404                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 405                     p_pic->i_buffer--;
 406                 p_sys->i_offset = 0;
 407
 408                 /* Parse the NAL */
 409                 if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
 410                 {
 411                     p_sys->i_state = STATE_NOSYNC;
 412                     break;
 413                 }
 414 #if 0
 415                 msg_Dbg( p_dec, "pts=%"PRId64" dts=%"PRId64,
 416                          p_pic->i_pts, p_pic->i_dts );
 417 #endif
 418
 419                 /* So p_block doesn't get re-added several times */
 420                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 421
 422                 p_sys->i_state = STATE_NOSYNC;
 423
 424                 return p_pic;
 425         }
 426     }
 427 }
 428
 429 /****************************************************************************
 430  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 431  * Will always use 4 byte 0 0 0 1 startcodes
 432  * Will prepend a SPS and PPS before each keyframe
 433  ****************************************************************************/
 434 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 435 {
 436     decoder_sys_t *p_sys = p_dec->p_sys;
 437     block_t       *p_block;
 438     block_t       *p_ret = NULL;
 439     uint8_t       *p;
 440
 441     if( !pp_block || !*pp_block )
 442         return NULL;
 443     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 444     {
 445         block_Release( *pp_block );
 446         return NULL;
 447     }
 448
 449     p_block = *pp_block;
 450     *pp_block = NULL;
 451
 452     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 453     {
 454         block_t *p_pic;
 455         int i_size = 0;
 456         int i;
 457
 458         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 459         {
 460             i_size = (i_size << 8) | (*p++);
 461         }
 462
 463         if( i_size <= 0 ||
 464             i_size > ( p_block->p_buffer + p_block->i_buffer - p ) )
 465         {
 466             msg_Err( p_dec, "Broken frame : size %d is too big", i_size );
 467             break;
 468         }
 469
 470         block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
 471         if( !p_part )
 472             break;
 473         p_part->i_dts = p_block->i_dts;
 474         p_part->i_pts = p_block->i_pts;
 475
 476         /* Parse the NAL */
 477         if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
 478         {
 479             block_ChainAppend( &p_ret, p_pic );
 480         }
 481         p += i_size;
 482     }
 483     block_Release( p_block );
 484
 485     return p_ret;
 486 }
 487
 488 static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
 489 {
 490     block_t *p_nal;
 491
 492     p_nal = block_New( p_dec, 4 + i_size );
 493     if( !p_nal ) return NULL;
 494
 495     /* Add start code */
 496     p_nal->p_buffer[0] = 0x00;
 497     p_nal->p_buffer[1] = 0x00;
 498     p_nal->p_buffer[2] = 0x00;
 499     p_nal->p_buffer[3] = 0x01;
 500
 501     /* Copy nalu */
 502     memcpy( &p_nal->p_buffer[4], p, i_size );
 503
 504     return p_nal;
 505 }
 506
 507 static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
 508                              uint8_t *src, int i_src )
 509 {
 510     uint8_t *end = &src[i_src];
 511     uint8_t *dst = malloc( i_src );
 512
 513     *pp_ret = dst;
 514
 515     if( dst )
 516     {
 517         while( src < end )
 518         {
 519             if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 520                 src[2] == 0x03 )
 521             {
 522                 *dst++ = 0x00;
 523                 *dst++ = 0x00;
 524
 525                 src += 3;
 526                 continue;
 527             }
 528             *dst++ = *src++;
 529         }
 530     }
 531     *pi_ret = dst - *pp_ret;
 532 }
 533
 534 static inline int bs_read_ue( bs_t *s )
 535 {
 536     int i = 0;
 537
 538     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 539     {
 540         i++;
 541     }
 542     return( ( 1 << i) - 1 + bs_read( s, i ) );
 543 }
 544
 545 static inline int bs_read_se( bs_t *s )
 546 {
 547     int val = bs_read_ue( s );
 548
 549     return val&0x01 ? (val+1)/2 : -(val/2);
 550 }
 551
 552 /*****************************************************************************
 553  * ParseNALBlock: parses annexB type NALs
 554  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 555  *****************************************************************************/
 556 static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
 557 {
 558     decoder_sys_t *p_sys = p_dec->p_sys;
 559     block_t *p_pic = NULL;
 560
 561     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 562     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 563
 564 #define OUTPUT \
 565     do {                                                      \
 566         if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I) \
 567             break;                                            \
 568                                                               \
 569         if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->p_sps && p_sys->p_pps ) \
 570         { \
 571             block_t *p_sps = block_Duplicate( p_sys->p_sps ); \
 572             block_t *p_pps = block_Duplicate( p_sys->p_pps ); \
 573             p_sps->i_dts = p_sys->p_frame->i_dts;           \
 574             p_sps->i_pts = p_sys->p_frame->i_pts;           \
 575             block_ChainAppend( &p_sps, p_pps );               \
 576             block_ChainAppend( &p_sps, p_sys->p_frame );      \
 577             p_sys->b_header = true;                       \
 578             p_pic = block_ChainGather( p_sps );               \
 579         } else { \
 580             p_pic = block_ChainGather( p_sys->p_frame ); \
 581         } \
 582         p_pic->i_length = 0;    /* FIXME */                   \
 583         p_pic->i_flags |= p_sys->slice.i_frame_type;          \
 584             \
 585         p_sys->slice.i_frame_type = 0;                        \
 586         p_sys->p_frame = NULL;                                \
 587         p_sys->b_slice = false;                           \
 588     } while(0)
 589
 590     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 591     {
 592         block_ChainRelease( p_sys->p_frame );
 593         msg_Warn( p_dec, "waiting for SPS/PPS" );
 594
 595         /* Reset context */
 596         p_sys->slice.i_frame_type = 0;
 597         p_sys->p_frame = NULL;
 598         p_sys->b_slice = false;
 599     }
 600
 601     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 602         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 603     {
 604         p_sys->b_slice = true;
 605         /* Fragment will be discarded later on */
 606     }
 607     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 608     {
 609         uint8_t *dec = NULL;
 610         int i_dec = 0, i_first_mb, i_slice_type;
 611         slice_t slice;
 612         bool b_pic;
 613         bs_t s;
 614
 615         /* do not convert the whole frame */
 616         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 617                          __MIN( p_frag->i_buffer - 5, 60 ) );
 618         bs_init( &s, dec, i_dec );
 619
 620         /* first_mb_in_slice */
 621         i_first_mb = bs_read_ue( &s );
 622
 623         /* slice_type */
 624         switch( (i_slice_type = bs_read_ue( &s )) )
 625         {
 626         case 0: case 5:
 627             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 628             break;
 629         case 1: case 6:
 630             slice.i_frame_type = BLOCK_FLAG_TYPE_B;
 631             break;
 632         case 2: case 7:
 633             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 634             break;
 635         case 3: case 8: /* SP */
 636             slice.i_frame_type = BLOCK_FLAG_TYPE_P;
 637             break;
 638         case 4: case 9:
 639             slice.i_frame_type = BLOCK_FLAG_TYPE_I;
 640             break;
 641         default:
 642             slice.i_frame_type = 0;
 643             break;
 644         }
 645
 646         /* */
 647         slice.i_nal_type = i_nal_type;
 648         slice.i_nal_ref_idc = i_nal_ref_idc;
 649
 650         slice.i_pic_parameter_set_id = bs_read_ue( &s );
 651         slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
 652
 653         slice.i_field_pic_flag = 0;
 654         slice.i_bottom_field_flag = -1;
 655         if( !p_sys->b_frame_mbs_only )
 656         {
 657             /* field_pic_flag */
 658             slice.i_field_pic_flag = bs_read( &s, 1 );
 659             if( slice.i_field_pic_flag )
 660                 slice.i_bottom_field_flag = bs_read( &s, 1 );
 661         }
 662
 663         slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
 664         if( slice.i_nal_type == NAL_SLICE_IDR )
 665             slice.i_idr_pic_id = bs_read_ue( &s );
 666
 667         slice.i_pic_order_cnt_lsb = -1;
 668         slice.i_delta_pic_order_cnt_bottom = -1;
 669         slice.i_delta_pic_order_cnt0 = 0;
 670         slice.i_delta_pic_order_cnt1 = 0;
 671         if( p_sys->i_pic_order_cnt_type == 0 )
 672         {
 673             slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
 674             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 675                 slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
 676         }
 677         else if( (p_sys->i_pic_order_cnt_type == 1) &&
 678                  (!p_sys->i_delta_pic_order_always_zero_flag) )
 679         {
 680             slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
 681             if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
 682                 slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
 683         }
 684
 685         /* Detection of the first VCL NAL unit of a primary coded picture
 686          * (cf. 7.4.1.2.4) */
 687         b_pic = false;
 688         if( slice.i_frame_num != p_sys->slice.i_frame_num ||
 689             slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
 690             slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
 691             slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
 692             b_pic = true;
 693         if( (slice.i_bottom_field_flag != -1) &&
 694             (p_sys->slice.i_bottom_field_flag != -1) &&
 695             (slice.i_bottom_field_flag != p_sys->slice.i_bottom_field_flag) )
 696             b_pic = true;
 697         if( p_sys->i_pic_order_cnt_type == 0 &&
 698             ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
 699               slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
 700             b_pic = true;
 701         else if( p_sys->i_pic_order_cnt_type == 1 &&
 702                  ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
 703                    slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
 704             b_pic = true;
 705         if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
 706             ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
 707                 b_pic = true;
 708
 709         /* */
 710         p_sys->slice = slice;
 711
 712         if( b_pic && p_sys->b_slice )
 713             OUTPUT;
 714
 715         p_sys->b_slice = true;
 716
 717         free( dec );
 718     }
 719     else if( i_nal_type == NAL_SPS )
 720     {
 721         uint8_t *dec = NULL;
 722         int     i_dec = 0;
 723         bs_t s;
 724         int i_tmp;
 725
 726         if( !p_sys->b_sps ) msg_Dbg( p_dec, "found NAL_SPS" );
 727
 728         p_sys->b_sps = true;
 729
 730         nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[5],
 731                          p_frag->i_buffer - 5 );
 732
 733         bs_init( &s, dec, i_dec );
 734         /* Skip profile(8), constraint_set012, reserver(5), level(8) */
 735         bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
 736         /* sps id */
 737         bs_read_ue( &s );
 738         /* Skip i_log2_max_frame_num */
 739         p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 740         if( p_sys->i_log2_max_frame_num > 12)
 741             p_sys->i_log2_max_frame_num = 12;
 742         /* Read poc_type */
 743         p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 744         if( p_sys->i_pic_order_cnt_type == 0 )
 745         {
 746             /* skip i_log2_max_poc_lsb */
 747             p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 748             if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 749                 p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 750         }
 751         else if( p_sys->i_pic_order_cnt_type == 1 )
 752         {
 753             int i_cycle;
 754             /* skip b_delta_pic_order_always_zero */
 755             p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 756             /* skip i_offset_for_non_ref_pic */
 757             bs_read_se( &s );
 758             /* skip i_offset_for_top_to_bottom_field */
 759             bs_read_se( &s );
 760             /* read i_num_ref_frames_in_poc_cycle */
 761             i_cycle = bs_read_ue( &s );
 762             if( i_cycle > 256 ) i_cycle = 256;
 763             while( i_cycle > 0 )
 764             {
 765                 /* skip i_offset_for_ref_frame */
 766                 bs_read_se(&s );
 767             }
 768         }
 769         /* i_num_ref_frames */
 770         bs_read_ue( &s );
 771         /* b_gaps_in_frame_num_value_allowed */
 772         bs_skip( &s, 1 );
 773
 774         /* Read size */
 775         p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 776         p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 777
 778         /* b_frame_mbs_only */
 779         p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 780         if( p_sys->b_frame_mbs_only == 0 )
 781         {
 782             bs_skip( &s, 1 );
 783         }
 784         /* b_direct8x8_inference */
 785         bs_skip( &s, 1 );
 786
 787         /* crop */
 788         i_tmp = bs_read( &s, 1 );
 789         if( i_tmp )
 790         {
 791             /* left */
 792             bs_read_ue( &s );
 793             /* right */
 794             bs_read_ue( &s );
 795             /* top */
 796             bs_read_ue( &s );
 797             /* bottom */
 798             bs_read_ue( &s );
 799         }
 800
 801         /* vui */
 802         i_tmp = bs_read( &s, 1 );
 803         if( i_tmp )
 804         {
 805             /* read the aspect ratio part if any FIXME check it */
 806             i_tmp = bs_read( &s, 1 );
 807             if( i_tmp )
 808             {
 809                 static const struct { int w, h; } sar[14] =
 810                 {
 811                     { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 812                     { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 813                     { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 814                     { 64, 33 }, { 160,99 },
 815                 };
 816                 int i_sar = bs_read( &s, 8 );
 817                 int w, h;
 818
 819                 if( i_sar < 14 )
 820                 {
 821                     w = sar[i_sar].w;
 822                     h = sar[i_sar].h;
 823                 }
 824                 else
 825                 {
 826                     w = bs_read( &s, 16 );
 827                     h = bs_read( &s, 16 );
 828                 }
 829                 if( h != 0 )
 830                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR * w /
 831                         h * p_dec->fmt_out.video.i_width /
 832                         p_dec->fmt_out.video.i_height;
 833                 else
 834                     p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 835             }
 836         }
 837
 838         free( dec );
 839
 840         if( p_sys->b_slice ) OUTPUT;
 841
 842         /* We have a new SPS */
 843         if( p_sys->p_sps ) block_Release( p_sys->p_sps );
 844         p_sys->p_sps = p_frag;
 845
 846         /* Do not append the SPS because we will insert it on keyframes */
 847         return p_pic;
 848     }
 849     else if( i_nal_type == NAL_PPS )
 850     {
 851         bs_t s;
 852
 853         bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 854         bs_read_ue( &s ); // pps id
 855         bs_read_ue( &s ); // sps id
 856         bs_skip( &s, 1 ); // entropy coding mode flag
 857         p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 858
 859         if( !p_sys->b_pps ) msg_Dbg( p_dec, "found NAL_PPS" );
 860         p_sys->b_pps = true;
 861
 862         /* TODO */
 863
 864         if( p_sys->b_slice ) OUTPUT;
 865
 866         /* We have a new PPS */
 867         if( p_sys->p_pps ) block_Release( p_sys->p_pps );
 868         p_sys->p_pps = p_frag;
 869
 870         /* Do not append the PPS because we will insert it on keyframes */
 871         return p_pic;
 872     }
 873     else if( i_nal_type == NAL_AU_DELIMITER ||
 874              i_nal_type == NAL_SEI ||
 875              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 876     {
 877         if( p_sys->b_slice ) OUTPUT;
 878     }
 879
 880 #undef OUTPUT
 881
 882     /* Append the block */
 883     block_ChainAppend( &p_sys->p_frame, p_frag );
 884
 885     return p_pic;
 886 }