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_common.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( N_("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 #define SPS_MAX (32)
  87 #define PPS_MAX (256)
  88 struct decoder_sys_t
  89 {
  90     block_bytestream_t bytestream;
  91
  92     int     i_state;
  93     size_t  i_offset;
  94     uint8_t startcode[4];
  95
  96     bool    b_slice;
  97     block_t *p_frame;
  98
  99     bool   b_header;
 100     bool   b_sps;
 101     bool   b_pps;
 102     block_t *pp_sps[SPS_MAX];
 103     block_t *pp_pps[PPS_MAX];
 104
 105     /* avcC data */
 106     int i_avcC_length_size;
 107
 108     /* Useful values of the Sequence Parameter Set */
 109     int i_log2_max_frame_num;
 110     int b_frame_mbs_only;
 111     int i_pic_order_cnt_type;
 112     int i_delta_pic_order_always_zero_flag;
 113     int i_log2_max_pic_order_cnt_lsb;
 114
 115     /* Value from Picture Parameter Set */
 116     int i_pic_order_present_flag;
 117
 118     /* Useful values of the Slice Header */
 119     slice_t slice;
 120
 121     /* */
 122     mtime_t i_frame_pts;
 123     mtime_t i_frame_dts;
 124 };
 125
 126 enum
 127 {
 128     STATE_NOSYNC,
 129     STATE_NEXT_SYNC,
 130 };
 131
 132 enum nal_unit_type_e
 133 {
 134     NAL_UNKNOWN = 0,
 135     NAL_SLICE   = 1,
 136     NAL_SLICE_DPA   = 2,
 137     NAL_SLICE_DPB   = 3,
 138     NAL_SLICE_DPC   = 4,
 139     NAL_SLICE_IDR   = 5,    /* ref_idc != 0 */
 140     NAL_SEI         = 6,    /* ref_idc == 0 */
 141     NAL_SPS         = 7,
 142     NAL_PPS         = 8,
 143     NAL_AU_DELIMITER= 9
 144     /* ref_idc == 0 for 6,9,10,11,12 */
 145 };
 146
 147 enum nal_priority_e
 148 {
 149     NAL_PRIORITY_DISPOSABLE = 0,
 150     NAL_PRIORITY_LOW        = 1,
 151     NAL_PRIORITY_HIGH       = 2,
 152     NAL_PRIORITY_HIGHEST    = 3,
 153 };
 154
 155 static block_t *ParseNALBlock( decoder_t *, bool *pb_used_ts, block_t * );
 156
 157 static block_t *CreateAnnexbNAL( decoder_t *, const uint8_t *p, int );
 158
 159 static block_t *OutputPicture( decoder_t *p_dec );
 160 static void PutSPS( decoder_t *p_dec, block_t *p_frag );
 161 static void PutPPS( decoder_t *p_dec, block_t *p_frag );
 162 static void ParseSlice( decoder_t *p_dec, bool *pb_new_picture, slice_t *p_slice,
 163                         int i_nal_ref_idc, int i_nal_type, const block_t *p_frag );
 164
 165
 166 /*****************************************************************************
 167  * Open: probe the packetizer and return score
 168  * When opening after demux, the packetizer is only loaded AFTER the decoder
 169  * That means that what you set in fmt_out is ignored by the decoder in this special case
 170  *****************************************************************************/
 171 static int Open( vlc_object_t *p_this )
 172 {
 173     decoder_t     *p_dec = (decoder_t*)p_this;
 174     decoder_sys_t *p_sys;
 175     int i;
 176
 177     if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
 178         p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
 179         p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
 180         p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
 181         p_dec->fmt_in.i_codec != VLC_FOURCC( 'D', 'A', 'V', 'C') &&
 182         p_dec->fmt_in.i_codec != VLC_FOURCC( 'x', '2', '6', '4') &&
 183         p_dec->fmt_in.i_codec != VLC_FOURCC( 'X', '2', '6', '4') &&
 184         ( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
 185           p_dec->fmt_in.i_extra < 7 ) )
 186     {
 187         return VLC_EGENERIC;
 188     }
 189
 190     /* Allocate the memory needed to store the decoder's structure */
 191     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 192     {
 193         return VLC_ENOMEM;
 194     }
 195     p_sys->i_state = STATE_NOSYNC;
 196     p_sys->i_offset = 0;
 197     p_sys->startcode[0] = 0;
 198     p_sys->startcode[1] = 0;
 199     p_sys->startcode[2] = 0;
 200     p_sys->startcode[3] = 1;
 201     p_sys->bytestream = block_BytestreamInit();
 202     p_sys->b_slice = false;
 203     p_sys->p_frame = NULL;
 204     p_sys->b_header= false;
 205     p_sys->b_sps   = false;
 206     p_sys->b_pps   = false;
 207     for( i = 0; i < SPS_MAX; i++ )
 208         p_sys->pp_sps[i] = NULL;
 209     for( i = 0; i < PPS_MAX; i++ )
 210         p_sys->pp_pps[i] = NULL;
 211
 212     p_sys->slice.i_nal_type = -1;
 213     p_sys->slice.i_nal_ref_idc = -1;
 214     p_sys->slice.i_idr_pic_id = -1;
 215     p_sys->slice.i_frame_num = -1;
 216     p_sys->slice.i_frame_type = 0;
 217     p_sys->slice.i_pic_parameter_set_id = -1;
 218     p_sys->slice.i_field_pic_flag = 0;
 219     p_sys->slice.i_bottom_field_flag = -1;
 220     p_sys->slice.i_pic_order_cnt_lsb = -1;
 221     p_sys->slice.i_delta_pic_order_cnt_bottom = -1;
 222
 223     p_sys->i_frame_dts = -1;
 224     p_sys->i_frame_pts = -1;
 225
 226     /* Setup properties */
 227     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 228     p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
 229
 230     if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
 231     {
 232         /* This type of stream is produced by mp4 and matroska
 233          * when we want to store it in another streamformat, you need to convert
 234          * The fmt_in.p_extra should ALWAYS contain the avcC
 235          * The fmt_out.p_extra should contain all the SPS and PPS with 4 byte startcodes */
 236         uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
 237         int i_sps, i_pps;
 238         bool b_dummy;
 239         int i;
 240
 241         /* Parse avcC */
 242         p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
 243
 244         /* Read SPS */
 245         i_sps = (*p++)&0x1f;
 246         for( i = 0; i < i_sps; i++ )
 247         {
 248             uint16_t i_length = GetWBE( p ); p += 2;
 249             if( i_length >
 250                 (uint8_t*)p_dec->fmt_in.p_extra + p_dec->fmt_in.i_extra - p )
 251             {
 252                 return VLC_EGENERIC;
 253             }
 254             block_t *p_sps = CreateAnnexbNAL( p_dec, p, i_length );
 255             if( !p_sps )
 256                 return VLC_EGENERIC;
 257             ParseNALBlock( p_dec, &b_dummy, p_sps );
 258             p += i_length;
 259         }
 260         /* Read PPS */
 261         i_pps = *p++;
 262         for( i = 0; i < i_pps; i++ )
 263         {
 264             uint16_t i_length = GetWBE( p ); p += 2;
 265             if( i_length >
 266                 (uint8_t*)p_dec->fmt_in.p_extra + p_dec->fmt_in.i_extra - p )
 267             {
 268                 return VLC_EGENERIC;
 269             }
 270             block_t *p_pps = CreateAnnexbNAL( p_dec, p, i_length );
 271             if( !p_pps )
 272                 return VLC_EGENERIC;
 273             ParseNALBlock( p_dec, &b_dummy, p_pps );
 274             p += i_length;
 275         }
 276         msg_Dbg( p_dec, "avcC length size=%d, sps=%d, pps=%d",
 277                  p_sys->i_avcC_length_size, i_sps, i_pps );
 278
 279         if( !p_sys->b_sps || !p_sys->b_pps )
 280             return VLC_EGENERIC;
 281
 282         /* FIXME: FFMPEG isn't happy at all if you leave this */
 283         if( p_dec->fmt_out.i_extra > 0 )
 284             free( p_dec->fmt_out.p_extra );
 285         p_dec->fmt_out.i_extra = 0;
 286         p_dec->fmt_out.p_extra = NULL;
 287
 288         /* Set the new extradata */
 289         for( i = 0; i < SPS_MAX; i++ )
 290         {
 291             if( p_sys->pp_sps[i] )
 292                 p_dec->fmt_out.i_extra += p_sys->pp_sps[i]->i_buffer;
 293         }
 294         for( i = 0; i < PPS_MAX; i++ )
 295         {
 296             if( p_sys->pp_pps[i] )
 297                 p_dec->fmt_out.i_extra += p_sys->pp_pps[i]->i_buffer;
 298         }
 299         p_dec->fmt_out.p_extra = malloc( p_dec->fmt_out.i_extra );
 300         if( p_dec->fmt_out.p_extra )
 301         {
 302             uint8_t *p_dst = p_dec->fmt_out.p_extra;
 303
 304             for( i = 0; i < SPS_MAX; i++ )
 305             {
 306                 if( p_sys->pp_sps[i] )
 307                 {
 308                     memcpy( p_dst, p_sys->pp_sps[i]->p_buffer, p_sys->pp_sps[i]->i_buffer );
 309                     p_dst += p_sys->pp_sps[i]->i_buffer;
 310                 }
 311             }
 312             for( i = 0; i < PPS_MAX; i++ )
 313             {
 314                 if( p_sys->pp_pps[i] )
 315                 {
 316                     memcpy( p_dst, p_sys->pp_pps[i]->p_buffer, p_sys->pp_pps[i]->i_buffer );
 317                     p_dst += p_sys->pp_pps[i]->i_buffer;
 318                 }
 319             }
 320             p_sys->b_header = true;
 321         }
 322         else
 323         {
 324             p_dec->fmt_out.i_extra = 0;
 325         }
 326
 327         /* Set callback */
 328         p_dec->pf_packetize = PacketizeAVC1;
 329     }
 330     else
 331     {
 332         /* This type of stream contains data with 3 of 4 byte startcodes
 333          * The fmt_in.p_extra MAY contain SPS/PPS with 4 byte startcodes
 334          * The fmt_out.p_extra should be the same */
 335
 336         /* Set callback */
 337         p_dec->pf_packetize = Packetize;
 338
 339         /* */
 340         if( p_dec->fmt_in.i_extra > 0 )
 341         {
 342             block_t *p_init = block_New( p_dec, p_dec->fmt_in.i_extra );
 343             block_t *p_pic;
 344
 345             memcpy( p_init->p_buffer, p_dec->fmt_in.p_extra,
 346                     p_dec->fmt_in.i_extra );
 347
 348             while( ( p_pic = Packetize( p_dec, &p_init ) ) )
 349             {
 350                 /* Should not occur because we should only receive SPS/PPS */
 351                 block_Release( p_pic );
 352             }
 353         }
 354     }
 355
 356     return VLC_SUCCESS;
 357 }
 358
 359 /*****************************************************************************
 360  * Close: clean up the packetizer
 361  *****************************************************************************/
 362 static void Close( vlc_object_t *p_this )
 363 {
 364     decoder_t *p_dec = (decoder_t*)p_this;
 365     decoder_sys_t *p_sys = p_dec->p_sys;
 366     int i;
 367
 368     if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
 369     for( i = 0; i < SPS_MAX; i++ )
 370     {
 371         if( p_sys->pp_sps[i] )
 372             block_Release( p_sys->pp_sps[i] );
 373     }
 374     for( i = 0; i < PPS_MAX; i++ )
 375     {
 376         if( p_sys->pp_pps[i] )
 377             block_Release( p_sys->pp_pps[i] );
 378     }
 379     block_BytestreamRelease( &p_sys->bytestream );
 380     free( p_sys );
 381 }
 382
 383 /****************************************************************************
 384  * Packetize: the whole thing
 385  * Search for the startcodes 3 or more bytes
 386  * Feed ParseNALBlock ALWAYS with 4 byte startcode prepended NALs
 387  ****************************************************************************/
 388 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 389 {
 390     decoder_sys_t *p_sys = p_dec->p_sys;
 391     block_t       *p_pic;
 392
 393     if( !pp_block || !*pp_block )
 394         return NULL;
 395
 396     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 397     {
 398         if( (*pp_block)->i_flags&BLOCK_FLAG_CORRUPTED )
 399         {
 400             p_sys->i_state = STATE_NOSYNC;
 401             block_BytestreamFlush( &p_sys->bytestream );
 402
 403             if( p_sys->p_frame )
 404                 block_ChainRelease( p_sys->p_frame );
 405             p_sys->p_frame = NULL;
 406             p_sys->slice.i_frame_type = 0;
 407             p_sys->b_slice = false;
 408         }
 409         block_Release( *pp_block );
 410         return NULL;
 411     }
 412
 413     block_BytestreamPush( &p_sys->bytestream, *pp_block );
 414
 415     for( ;; )
 416     {
 417         bool b_used_ts;
 418
 419         switch( p_sys->i_state )
 420         {
 421             case STATE_NOSYNC:
 422                 /* Skip until 3 byte startcode 0 0 1 */
 423                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 424                       &p_sys->i_offset, p_sys->startcode+1, 3 ) == VLC_SUCCESS)
 425                 {
 426                     p_sys->i_state = STATE_NEXT_SYNC;
 427                 }
 428
 429                 if( p_sys->i_offset )
 430                 {
 431                     /* skip the data */
 432                     block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
 433                     p_sys->i_offset = 0;
 434                     block_BytestreamFlush( &p_sys->bytestream );
 435                 }
 436
 437                 if( p_sys->i_state != STATE_NEXT_SYNC )
 438                 {
 439                     /* Need more data */
 440                     return NULL;
 441                 }
 442
 443                 p_sys->i_offset = 1; /* To find next startcode */
 444
 445             case STATE_NEXT_SYNC:
 446                 /* Find the next 3 byte startcode 0 0 1*/
 447                 if( block_FindStartcodeFromOffset( &p_sys->bytestream,
 448                       &p_sys->i_offset, p_sys->startcode+1, 3 ) != VLC_SUCCESS)
 449                 {
 450                     /* Need more data */
 451                     return NULL;
 452                 }
 453                 block_BytestreamFlush( &p_sys->bytestream );
 454
 455                 /* Get the new fragment and set the pts/dts */
 456                 block_t *p_block_bytestream = p_sys->bytestream.p_block;
 457
 458                 p_pic = block_New( p_dec, p_sys->i_offset +1 );
 459                 p_pic->i_pts = p_block_bytestream->i_pts;
 460                 p_pic->i_dts = p_block_bytestream->i_dts;
 461
 462                 /* Force 4 byte startcode 0 0 0 1 */
 463                 p_pic->p_buffer[0] = 0;
 464
 465                 block_GetBytes( &p_sys->bytestream, &p_pic->p_buffer[1],
 466                                 p_pic->i_buffer-1 );
 467
 468                 /* Remove trailing 0 bytes */
 469                 while( p_pic->i_buffer && (!p_pic->p_buffer[p_pic->i_buffer-1] ) )
 470                     p_pic->i_buffer--;
 471                 p_sys->i_offset = 0;
 472
 473                 /* Parse the NAL */
 474                 p_pic = ParseNALBlock( p_dec, &b_used_ts, p_pic );
 475                 if( b_used_ts )
 476                 {
 477                     p_block_bytestream->i_dts = -1;
 478                     p_block_bytestream->i_pts = -1;
 479                 }
 480
 481                 if( !p_pic )
 482                 {
 483                     p_sys->i_state = STATE_NOSYNC;
 484                     break;
 485                 }
 486 #if 0
 487                 msg_Dbg( p_dec, "pts=%"PRId64" dts=%"PRId64,
 488                          p_pic->i_pts, p_pic->i_dts );
 489 #endif
 490
 491                 /* So p_block doesn't get re-added several times */
 492                 *pp_block = block_BytestreamPop( &p_sys->bytestream );
 493
 494                 p_sys->i_state = STATE_NOSYNC;
 495
 496                 return p_pic;
 497         }
 498     }
 499 }
 500
 501 /****************************************************************************
 502  * PacketizeAVC1: Takes VCL blocks of data and creates annexe B type NAL stream
 503  * Will always use 4 byte 0 0 0 1 startcodes
 504  * Will prepend a SPS and PPS before each keyframe
 505  ****************************************************************************/
 506 static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
 507 {
 508     decoder_sys_t *p_sys = p_dec->p_sys;
 509     block_t       *p_block;
 510     block_t       *p_ret = NULL;
 511     uint8_t       *p;
 512
 513     if( !pp_block || !*pp_block )
 514         return NULL;
 515     if( (*pp_block)->i_flags&(BLOCK_FLAG_DISCONTINUITY|BLOCK_FLAG_CORRUPTED) )
 516     {
 517         block_Release( *pp_block );
 518         return NULL;
 519     }
 520
 521     p_block = *pp_block;
 522     *pp_block = NULL;
 523
 524     for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
 525     {
 526         block_t *p_pic;
 527         bool b_dummy;
 528         int i_size = 0;
 529         int i;
 530
 531         for( i = 0; i < p_sys->i_avcC_length_size; i++ )
 532         {
 533             i_size = (i_size << 8) | (*p++);
 534         }
 535
 536         if( i_size <= 0 ||
 537             i_size > ( p_block->p_buffer + p_block->i_buffer - p ) )
 538         {
 539             msg_Err( p_dec, "Broken frame : size %d is too big", i_size );
 540             break;
 541         }
 542
 543         block_t *p_part = CreateAnnexbNAL( p_dec, p, i_size );
 544         if( !p_part )
 545             break;
 546
 547         p_part->i_dts = p_block->i_dts;
 548         p_part->i_pts = p_block->i_pts;
 549
 550         /* Parse the NAL */
 551         if( ( p_pic = ParseNALBlock( p_dec, &b_dummy, p_part ) ) )
 552         {
 553             block_ChainAppend( &p_ret, p_pic );
 554         }
 555         p += i_size;
 556     }
 557     block_Release( p_block );
 558
 559     return p_ret;
 560 }
 561
 562 /****************************************************************************
 563  * Helpers
 564  ****************************************************************************/
 565 static block_t *CreateAnnexbNAL( decoder_t *p_dec, const uint8_t *p, int i_size )
 566 {
 567     block_t *p_nal;
 568
 569     p_nal = block_New( p_dec, 4 + i_size );
 570     if( !p_nal ) return NULL;
 571
 572     /* Add start code */
 573     p_nal->p_buffer[0] = 0x00;
 574     p_nal->p_buffer[1] = 0x00;
 575     p_nal->p_buffer[2] = 0x00;
 576     p_nal->p_buffer[3] = 0x01;
 577
 578     /* Copy nalu */
 579     memcpy( &p_nal->p_buffer[4], p, i_size );
 580
 581     VLC_UNUSED(p_dec);
 582     return p_nal;
 583 }
 584
 585 static void CreateDecodedNAL( uint8_t **pp_ret, int *pi_ret,
 586                               const uint8_t *src, int i_src )
 587 {
 588     const uint8_t *end = &src[i_src];
 589     uint8_t *dst = malloc( i_src );
 590
 591     *pp_ret = dst;
 592
 593     if( dst )
 594     {
 595         while( src < end )
 596         {
 597             if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
 598                 src[2] == 0x03 )
 599             {
 600                 *dst++ = 0x00;
 601                 *dst++ = 0x00;
 602
 603                 src += 3;
 604                 continue;
 605             }
 606             *dst++ = *src++;
 607         }
 608     }
 609     *pi_ret = dst - *pp_ret;
 610 }
 611
 612 static inline int bs_read_ue( bs_t *s )
 613 {
 614     int i = 0;
 615
 616     while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
 617     {
 618         i++;
 619     }
 620     return( ( 1 << i) - 1 + bs_read( s, i ) );
 621 }
 622
 623 static inline int bs_read_se( bs_t *s )
 624 {
 625     int val = bs_read_ue( s );
 626
 627     return val&0x01 ? (val+1)/2 : -(val/2);
 628 }
 629
 630 /*****************************************************************************
 631  * ParseNALBlock: parses annexB type NALs
 632  * All p_frag blocks are required to start with 0 0 0 1 4-byte startcode
 633  *****************************************************************************/
 634 static block_t *ParseNALBlock( decoder_t *p_dec, bool *pb_used_ts, block_t *p_frag )
 635 {
 636     decoder_sys_t *p_sys = p_dec->p_sys;
 637     block_t *p_pic = NULL;
 638
 639     const int i_nal_ref_idc = (p_frag->p_buffer[4] >> 5)&0x03;
 640     const int i_nal_type = p_frag->p_buffer[4]&0x1f;
 641     const mtime_t i_frag_dts = p_frag->i_dts;
 642     const mtime_t i_frag_pts = p_frag->i_pts;
 643
 644     if( p_sys->b_slice && ( !p_sys->b_sps || !p_sys->b_pps ) )
 645     {
 646         block_ChainRelease( p_sys->p_frame );
 647         msg_Warn( p_dec, "waiting for SPS/PPS" );
 648
 649         /* Reset context */
 650         p_sys->slice.i_frame_type = 0;
 651         p_sys->p_frame = NULL;
 652         p_sys->b_slice = false;
 653     }
 654
 655     if( ( !p_sys->b_sps || !p_sys->b_pps ) &&
 656         i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 657     {
 658         p_sys->b_slice = true;
 659         /* Fragment will be discarded later on */
 660     }
 661     else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
 662     {
 663         slice_t slice;
 664         bool  b_new_picture;
 665
 666         ParseSlice( p_dec, &b_new_picture, &slice, i_nal_ref_idc, i_nal_type, p_frag );
 667
 668         /* */
 669         if( b_new_picture && p_sys->b_slice )
 670             p_pic = OutputPicture( p_dec );
 671
 672         /* */
 673         p_sys->slice = slice;
 674         p_sys->b_slice = true;
 675     }
 676     else if( i_nal_type == NAL_SPS )
 677     {
 678         if( p_sys->b_slice )
 679             p_pic = OutputPicture( p_dec );
 680
 681         PutSPS( p_dec, p_frag );
 682
 683         /* Do not append the SPS because we will insert it on keyframes */
 684         p_frag = NULL;
 685     }
 686     else if( i_nal_type == NAL_PPS )
 687     {
 688         if( p_sys->b_slice )
 689             p_pic = OutputPicture( p_dec );
 690
 691         PutPPS( p_dec, p_frag );
 692
 693         /* Do not append the PPS because we will insert it on keyframes */
 694         p_frag = NULL;
 695     }
 696     else if( i_nal_type == NAL_AU_DELIMITER ||
 697              i_nal_type == NAL_SEI ||
 698              ( i_nal_type >= 13 && i_nal_type <= 18 ) )
 699     {
 700         if( p_sys->b_slice )
 701             p_pic = OutputPicture( p_dec );
 702
 703         /* TODO parse SEI for CC support */
 704     }
 705
 706     /* Append the block */
 707     if( p_frag )
 708         block_ChainAppend( &p_sys->p_frame, p_frag );
 709
 710     *pb_used_ts = false;
 711     if( p_sys->i_frame_dts < 0 && p_sys->i_frame_pts < 0 )
 712     {
 713         p_sys->i_frame_dts = i_frag_dts;
 714         p_sys->i_frame_pts = i_frag_pts;
 715         *pb_used_ts = true;
 716     }
 717     return p_pic;
 718 }
 719
 720 static block_t *OutputPicture( decoder_t *p_dec )
 721 {
 722     decoder_sys_t *p_sys = p_dec->p_sys;
 723     block_t *p_pic;
 724
 725     if( !p_sys->b_header && p_sys->slice.i_frame_type != BLOCK_FLAG_TYPE_I)
 726         return NULL;
 727
 728     if( p_sys->slice.i_frame_type == BLOCK_FLAG_TYPE_I && p_sys->b_sps && p_sys->b_pps )
 729     {
 730         block_t *p_list = NULL;
 731         int i;
 732
 733         for( i = 0; i < SPS_MAX; i++ )
 734         {
 735             if( p_sys->pp_sps[i] )
 736                 block_ChainAppend( &p_list, block_Duplicate( p_sys->pp_sps[i] ) );
 737         }
 738         for( i = 0; i < PPS_MAX; i++ )
 739         {
 740             if( p_sys->pp_pps[i] )
 741                 block_ChainAppend( &p_list, block_Duplicate( p_sys->pp_pps[i] ) );
 742         }
 743         if( p_list )
 744             p_sys->b_header = true;
 745
 746         block_ChainAppend( &p_list, p_sys->p_frame );
 747         p_pic = block_ChainGather( p_list );
 748     }
 749     else
 750     {
 751         p_pic = block_ChainGather( p_sys->p_frame );
 752     }
 753     p_pic->i_dts = p_sys->i_frame_dts;
 754     p_pic->i_pts = p_sys->i_frame_pts;
 755     p_pic->i_length = 0;    /* FIXME */
 756     p_pic->i_flags |= p_sys->slice.i_frame_type;
 757
 758     p_sys->slice.i_frame_type = 0;
 759     p_sys->p_frame = NULL;
 760     p_sys->i_frame_dts = -1;
 761     p_sys->i_frame_pts = -1;
 762     p_sys->b_slice = false;
 763
 764     return p_pic;
 765 }
 766
 767 static void PutSPS( decoder_t *p_dec, block_t *p_frag )
 768 {
 769     decoder_sys_t *p_sys = p_dec->p_sys;
 770
 771     uint8_t *pb_dec = NULL;
 772     int     i_dec = 0;
 773     bs_t s;
 774     int i_tmp;
 775     int i_sps_id;
 776
 777     CreateDecodedNAL( &pb_dec, &i_dec, &p_frag->p_buffer[5],
 778                      p_frag->i_buffer - 5 );
 779
 780     bs_init( &s, pb_dec, i_dec );
 781     int i_profile_idc = bs_read( &s, 8 );
 782     /* Skip constraint_set0123, reserved(4), level(8) */
 783     bs_skip( &s, 1+1+1+1 + 4 + 8 );
 784     /* sps id */
 785     i_sps_id = bs_read_ue( &s );
 786     if( i_sps_id >= SPS_MAX )
 787     {
 788         msg_Warn( p_dec, "invalid SPS (sps_id=%d)", i_sps_id );
 789         free( pb_dec );
 790         block_Release( p_frag );
 791         return;
 792     }
 793
 794     if( 100 == i_profile_idc || 110 == i_profile_idc ||
 795         122 == i_profile_idc || 244 == i_profile_idc ||
 796          44 == i_profile_idc ||  83 == i_profile_idc ||
 797          86 == i_profile_idc )
 798     {
 799         /* chroma_format_idc */
 800         int i_chroma_format_idc = bs_read_ue( &s );
 801         if( 3 == i_chroma_format_idc )
 802             /* seperate_colour_plane_flag */
 803             bs_skip( &s, 1 );
 804         /* bit_depth_luma_minus8 */
 805         bs_read_ue( &s );
 806         /* bit_depth_chroma_minus8 */
 807         bs_read_ue( &s );
 808         /* qpprime_y_zero_transform_bypass_flag */
 809         bs_skip( &s, 1 );
 810         /* seq_scaling_matrix_present_flag */
 811         i_tmp = bs_read( &s, 1 );
 812         if( i_tmp )
 813         {
 814             for( int i = 0; i < ((3 != i_chroma_format_idc) ? 8 : 12); i++ ) {
 815                 /* seq_scaling_list_present_flag[i] */
 816                 i_tmp = bs_read( &s, 1 );
 817                 if( !i_tmp )
 818                     continue;
 819                 int i_size_of_scaling_list = (i < 6 ) ? 16 : 64;
 820                 /* scaling_list (...) */
 821                 int i_lastscale = 8;
 822                 int i_nextscale = 8;
 823                 for( int j = 0; j < i_size_of_scaling_list; j++ ) {
 824                     if( i_nextscale != 0 ) {
 825                         /* delta_scale */
 826                         i_tmp = bs_read( &s, 1 );
 827                         i_nextscale = ( i_lastscale + i_tmp + 256 ) % 256;
 828                         /* useDefaultScalingMatrixFlag = ... */
 829                     }
 830                     /* scalinglist[j] */
 831                     i_lastscale = ( i_nextscale == 0 ) ? i_lastscale : i_nextscale;
 832                 }
 833             }
 834         }
 835     }
 836
 837     /* Skip i_log2_max_frame_num */
 838     p_sys->i_log2_max_frame_num = bs_read_ue( &s );
 839     if( p_sys->i_log2_max_frame_num > 12)
 840         p_sys->i_log2_max_frame_num = 12;
 841     /* Read poc_type */
 842     p_sys->i_pic_order_cnt_type = bs_read_ue( &s );
 843     if( p_sys->i_pic_order_cnt_type == 0 )
 844     {
 845         /* skip i_log2_max_poc_lsb */
 846         p_sys->i_log2_max_pic_order_cnt_lsb = bs_read_ue( &s );
 847         if( p_sys->i_log2_max_pic_order_cnt_lsb > 12 )
 848             p_sys->i_log2_max_pic_order_cnt_lsb = 12;
 849     }
 850     else if( p_sys->i_pic_order_cnt_type == 1 )
 851     {
 852         int i_cycle;
 853         /* skip b_delta_pic_order_always_zero */
 854         p_sys->i_delta_pic_order_always_zero_flag = bs_read( &s, 1 );
 855         /* skip i_offset_for_non_ref_pic */
 856         bs_read_se( &s );
 857         /* skip i_offset_for_top_to_bottom_field */
 858         bs_read_se( &s );
 859         /* read i_num_ref_frames_in_poc_cycle */
 860         i_cycle = bs_read_ue( &s );
 861         if( i_cycle > 256 ) i_cycle = 256;
 862         while( i_cycle > 0 )
 863         {
 864             /* skip i_offset_for_ref_frame */
 865             bs_read_se(&s );
 866             i_cycle--;
 867         }
 868     }
 869     /* i_num_ref_frames */
 870     bs_read_ue( &s );
 871     /* b_gaps_in_frame_num_value_allowed */
 872     bs_skip( &s, 1 );
 873
 874     /* Read size */
 875     p_dec->fmt_out.video.i_width  = 16 * ( bs_read_ue( &s ) + 1 );
 876     p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
 877
 878     /* b_frame_mbs_only */
 879     p_sys->b_frame_mbs_only = bs_read( &s, 1 );
 880     if( p_sys->b_frame_mbs_only == 0 )
 881     {
 882         bs_skip( &s, 1 );
 883     }
 884     /* b_direct8x8_inference */
 885     bs_skip( &s, 1 );
 886
 887     /* crop */
 888     i_tmp = bs_read( &s, 1 );
 889     if( i_tmp )
 890     {
 891         /* left */
 892         bs_read_ue( &s );
 893         /* right */
 894         bs_read_ue( &s );
 895         /* top */
 896         bs_read_ue( &s );
 897         /* bottom */
 898         bs_read_ue( &s );
 899     }
 900
 901     /* vui */
 902     i_tmp = bs_read( &s, 1 );
 903     if( i_tmp )
 904     {
 905         /* read the aspect ratio part if any */
 906         i_tmp = bs_read( &s, 1 );
 907         if( i_tmp )
 908         {
 909             static const struct { int w, h; } sar[17] =
 910             {
 911                 { 0,   0 }, { 1,   1 }, { 12, 11 }, { 10, 11 },
 912                 { 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
 913                 { 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
 914                 { 64, 33 }, { 160,99 }, {  4,  3 }, {  3,  2 },
 915                 {  2,  1 },
 916             };
 917             int i_sar = bs_read( &s, 8 );
 918             int w, h;
 919
 920             if( i_sar < 17 )
 921             {
 922                 w = sar[i_sar].w;
 923                 h = sar[i_sar].h;
 924             }
 925             else if( i_sar == 255 )
 926             {
 927                 w = bs_read( &s, 16 );
 928                 h = bs_read( &s, 16 );
 929             }
 930             else
 931             {
 932                 w = 0;
 933                 h = 0;
 934             }
 935
 936             if( h != 0 )
 937                 p_dec->fmt_out.video.i_aspect = (int64_t)VOUT_ASPECT_FACTOR *
 938                         ( w * p_dec->fmt_out.video.i_width ) /
 939                         ( h * p_dec->fmt_out.video.i_height);
 940             else
 941                 p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
 942         }
 943     }
 944
 945     free( pb_dec );
 946
 947     /* We have a new SPS */
 948     if( !p_sys->b_sps )
 949         msg_Dbg( p_dec, "found NAL_SPS (sps_id=%d)", i_sps_id );
 950     p_sys->b_sps = true;
 951
 952     if( p_sys->pp_sps[i_sps_id] )
 953         block_Release( p_sys->pp_sps[i_sps_id] );
 954     p_sys->pp_sps[i_sps_id] = p_frag;
 955 }
 956
 957 static void PutPPS( decoder_t *p_dec, block_t *p_frag )
 958 {
 959     decoder_sys_t *p_sys = p_dec->p_sys;
 960     bs_t s;
 961     int i_pps_id;
 962     int i_sps_id;
 963
 964     bs_init( &s, &p_frag->p_buffer[5], p_frag->i_buffer - 5 );
 965     i_pps_id = bs_read_ue( &s ); // pps id
 966     i_sps_id = bs_read_ue( &s ); // sps id
 967     if( i_pps_id >= PPS_MAX || i_sps_id >= SPS_MAX )
 968     {
 969         msg_Warn( p_dec, "invalid PPS (pps_id=%d sps_id=%d)", i_pps_id, i_sps_id );
 970         block_Release( p_frag );
 971         return;
 972     }
 973     bs_skip( &s, 1 ); // entropy coding mode flag
 974     p_sys->i_pic_order_present_flag = bs_read( &s, 1 );
 975     /* TODO */
 976
 977     /* We have a new PPS */
 978     if( !p_sys->b_pps )
 979         msg_Dbg( p_dec, "found NAL_PPS (pps_id=%d sps_id=%d)", i_pps_id, i_sps_id );
 980     p_sys->b_pps = true;
 981
 982     if( p_sys->pp_pps[i_pps_id] )
 983         block_Release( p_sys->pp_pps[i_pps_id] );
 984     p_sys->pp_pps[i_pps_id] = p_frag;
 985 }
 986
 987 static void ParseSlice( decoder_t *p_dec, bool *pb_new_picture, slice_t *p_slice,
 988                         int i_nal_ref_idc, int i_nal_type, const block_t *p_frag )
 989 {
 990     decoder_sys_t *p_sys = p_dec->p_sys;
 991     uint8_t *pb_dec;
 992     int i_dec;
 993     int i_first_mb, i_slice_type;
 994     slice_t slice;
 995     bs_t s;
 996
 997     /* do not convert the whole frame */
 998     CreateDecodedNAL( &pb_dec, &i_dec, &p_frag->p_buffer[5],
 999                      __MIN( p_frag->i_buffer - 5, 60 ) );
1000     bs_init( &s, pb_dec, i_dec );
1001
1002     /* first_mb_in_slice */
1003     i_first_mb = bs_read_ue( &s );
1004
1005     /* slice_type */
1006     switch( (i_slice_type = bs_read_ue( &s )) )
1007     {
1008     case 0: case 5:
1009         slice.i_frame_type = BLOCK_FLAG_TYPE_P;
1010         break;
1011     case 1: case 6:
1012         slice.i_frame_type = BLOCK_FLAG_TYPE_B;
1013         break;
1014     case 2: case 7:
1015         slice.i_frame_type = BLOCK_FLAG_TYPE_I;
1016         break;
1017     case 3: case 8: /* SP */
1018         slice.i_frame_type = BLOCK_FLAG_TYPE_P;
1019         break;
1020     case 4: case 9:
1021         slice.i_frame_type = BLOCK_FLAG_TYPE_I;
1022         break;
1023     default:
1024         slice.i_frame_type = 0;
1025         break;
1026     }
1027
1028     /* */
1029     slice.i_nal_type = i_nal_type;
1030     slice.i_nal_ref_idc = i_nal_ref_idc;
1031
1032     slice.i_pic_parameter_set_id = bs_read_ue( &s );
1033     slice.i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
1034
1035     slice.i_field_pic_flag = 0;
1036     slice.i_bottom_field_flag = -1;
1037     if( !p_sys->b_frame_mbs_only )
1038     {
1039         /* field_pic_flag */
1040         slice.i_field_pic_flag = bs_read( &s, 1 );
1041         if( slice.i_field_pic_flag )
1042             slice.i_bottom_field_flag = bs_read( &s, 1 );
1043     }
1044
1045     slice.i_idr_pic_id = p_sys->slice.i_idr_pic_id;
1046     if( slice.i_nal_type == NAL_SLICE_IDR )
1047         slice.i_idr_pic_id = bs_read_ue( &s );
1048
1049     slice.i_pic_order_cnt_lsb = -1;
1050     slice.i_delta_pic_order_cnt_bottom = -1;
1051     slice.i_delta_pic_order_cnt0 = 0;
1052     slice.i_delta_pic_order_cnt1 = 0;
1053     if( p_sys->i_pic_order_cnt_type == 0 )
1054     {
1055         slice.i_pic_order_cnt_lsb = bs_read( &s, p_sys->i_log2_max_pic_order_cnt_lsb + 4 );
1056         if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
1057             slice.i_delta_pic_order_cnt_bottom = bs_read_se( &s );
1058     }
1059     else if( (p_sys->i_pic_order_cnt_type == 1) &&
1060              (!p_sys->i_delta_pic_order_always_zero_flag) )
1061     {
1062         slice.i_delta_pic_order_cnt0 = bs_read_se( &s );
1063         if( p_sys->i_pic_order_present_flag && !slice.i_field_pic_flag )
1064             slice.i_delta_pic_order_cnt1 = bs_read_se( &s );
1065     }
1066     free( pb_dec );
1067
1068     /* Detection of the first VCL NAL unit of a primary coded picture
1069      * (cf. 7.4.1.2.4) */
1070     bool b_pic = false;
1071     if( slice.i_frame_num != p_sys->slice.i_frame_num ||
1072         slice.i_pic_parameter_set_id != p_sys->slice.i_pic_parameter_set_id ||
1073         slice.i_field_pic_flag != p_sys->slice.i_field_pic_flag ||
1074         slice.i_nal_ref_idc != p_sys->slice.i_nal_ref_idc )
1075         b_pic = true;
1076     if( (slice.i_bottom_field_flag != -1) &&
1077         (p_sys->slice.i_bottom_field_flag != -1) &&
1078         (slice.i_bottom_field_flag != p_sys->slice.i_bottom_field_flag) )
1079         b_pic = true;
1080     if( p_sys->i_pic_order_cnt_type == 0 &&
1081         ( slice.i_pic_order_cnt_lsb != p_sys->slice.i_pic_order_cnt_lsb ||
1082           slice.i_delta_pic_order_cnt_bottom != p_sys->slice.i_delta_pic_order_cnt_bottom ) )
1083         b_pic = true;
1084     else if( p_sys->i_pic_order_cnt_type == 1 &&
1085              ( slice.i_delta_pic_order_cnt0 != p_sys->slice.i_delta_pic_order_cnt0 ||
1086                slice.i_delta_pic_order_cnt1 != p_sys->slice.i_delta_pic_order_cnt1 ) )
1087         b_pic = true;
1088     if( ( slice.i_nal_type == NAL_SLICE_IDR || p_sys->slice.i_nal_type == NAL_SLICE_IDR ) &&
1089         ( slice.i_nal_type != p_sys->slice.i_nal_type || slice.i_idr_pic_id != p_sys->slice.i_idr_pic_id ) )
1090             b_pic = true;
1091
1092     /* */
1093     *pb_new_picture = b_pic;
1094     *p_slice = slice;
1095 }
1096
1097