git.sesse.net Git - vlc/blob - src/video_parser/vpar_headers.c

   1 /*****************************************************************************
   2  * vpar_headers.c : headers parsing
   3  * (c)1999 VideoLAN
   4  *****************************************************************************/
   5
   6 /*****************************************************************************
   7  * Preamble
   8  *****************************************************************************/
   9 #include <errno.h>
  10 #include <stdlib.h>
  11 #include <stdio.h>
  12 #include <unistd.h>
  13 #include <string.h>
  14 #include <sys/uio.h>
  15 #include <X11/Xlib.h>
  16 #include <X11/extensions/XShm.h>
  17
  18 #include "config.h"
  19 #include "common.h"
  20 #include "mtime.h"
  21 #include "vlc_thread.h"
  22
  23 #include "intf_msg.h"
  24 #include "debug.h"                    /* ?? temporaire, requis par netlist.h */
  25
  26 #include "input.h"
  27 #include "input_netlist.h"
  28 #include "decoder_fifo.h"
  29 #include "video.h"
  30 #include "video_output.h"
  31
  32 #include "vdec_idct.h"
  33 #include "video_decoder.h"
  34 #include "vdec_motion.h"
  35
  36 #include "vpar_blocks.h"
  37 #include "vpar_headers.h"
  38 #include "video_fifo.h"
  39 #include "vpar_synchro.h"
  40 #include "video_parser.h"
  41 #include "vpar_motion.h"
  42
  43 /*
  44  * Local prototypes
  45  */
  46 static __inline__ void NextStartCode( vpar_thread_t * p_vpar );
  47 static void SequenceHeader( vpar_thread_t * p_vpar );
  48 static void GroupHeader( vpar_thread_t * p_vpar );
  49 static void PictureHeader( vpar_thread_t * p_vpar );
  50 static void SliceHeader00( vpar_thread_t * p_vpar,
  51                            int * pi_mb_address, int i_mb_base,
  52                            u32 i_vert_code );
  53 static void SliceHeader01( vpar_thread_t * p_vpar,
  54                            int * pi_mb_address, int i_mb_base,
  55                            u32 i_vert_code );
  56 static void SliceHeader10( vpar_thread_t * p_vpar,
  57                            int * pi_mb_address, int i_mb_base,
  58                            u32 i_vert_code );
  59 static void SliceHeader11( vpar_thread_t * p_vpar,
  60                            int * pi_mb_address, int i_mb_base,
  61                            u32 i_vert_code );
  62 static __inline__ void SliceHeader( vpar_thread_t * p_vpar,
  63                                     int * pi_mb_address, int i_mb_base,
  64                                     u32 i_vert_code );
  65 static void ExtensionAndUserData( vpar_thread_t * p_vpar );
  66 static void QuantMatrixExtension( vpar_thread_t * p_vpar );
  67 static void SequenceScalableExtension( vpar_thread_t * p_vpar );
  68 static void SequenceDisplayExtension( vpar_thread_t * p_vpar );
  69 static void PictureDisplayExtension( vpar_thread_t * p_vpar );
  70 static void PictureSpatialScalableExtension( vpar_thread_t * p_vpar );
  71 static void PictureTemporalScalableExtension( vpar_thread_t * p_vpar );
  72 static void CopyrightExtension( vpar_thread_t * p_vpar );
  73
  74 /*
  75  * Standard variables
  76  */
  77
  78 /*****************************************************************************
  79  * pi_default_intra_quant : default quantization matrix
  80  *****************************************************************************/
  81 #ifndef VDEC_DFT
  82 int pi_default_intra_quant[] =
  83 {
  84     8,  16, 19, 22, 26, 27, 29, 34,
  85     16, 16, 22, 24, 27, 29, 34, 37,
  86     19, 22, 26, 27, 29, 34, 34, 38,
  87     22, 22, 26, 27, 29, 34, 37, 40,
  88     22, 26, 27, 29, 32, 35, 40, 48,
  89     26, 27, 29, 32, 35, 40, 48, 58,
  90     26, 27, 29, 34, 38, 46, 56, 69,
  91     27, 29, 35, 38, 46, 56, 69, 83
  92 };
  93 #else
  94 int pi_default_intra_quant[] =
  95 {
  96     2048,   5681,   6355,   6623,   6656,   5431,   4018,   2401,
  97     5681,   7880,   10207,  10021,  9587,   8091,   6534,   3625,
  98     6355,   10207,  11363,  10619,  9700,   8935,   6155,   3507,
  99     6623,   9186,   10226,  9557,   8730,   8041,   6028,   3322,
 100     5632,   9232,   9031,   8730,   8192,   7040,   5542,   3390,
 101     5230,   7533,   7621,   7568,   7040,   6321,   5225,   3219,
 102     3602,   5189,   5250,   5539,   5265,   5007,   4199,   2638,
 103     1907,   2841,   3230,   3156,   3249,   3108,   2638,   1617
 104 };
 105 #endif
 106
 107 /*****************************************************************************
 108  * pi_default_nonintra_quant : default quantization matrix
 109  *****************************************************************************/
 110 #ifndef VDEC_DFT
 111 int pi_default_nonintra_quant[] =
 112 {
 113     16, 16, 16, 16, 16, 16, 16, 16,
 114     16, 16, 16, 16, 16, 16, 16, 16,
 115     16, 16, 16, 16, 16, 16, 16, 16,
 116     16, 16, 16, 16, 16, 16, 16, 16,
 117     16, 16, 16, 16, 16, 16, 16, 16,
 118     16, 16, 16, 16, 16, 16, 16, 16,
 119     16, 16, 16, 16, 16, 16, 16, 16,
 120     16, 16, 16, 16, 16, 16, 16, 16
 121 };
 122 #else
 123 int pi_default_nonintra_quanit[] =
 124 {
 125     4096,   5680,   5344,   4816,   4096,   3216,   2224,   1136,
 126     5680,   7888,   7424,   6688,   5680,   4464,   3072,   1568,
 127     5344,   7424,   6992,   6288,   5344,   4208,   2896,   1472,
 128     4816,   6688,   6288,   5664,   4816,   3792,   2608,   1328,
 129     4096,   5680,   5344,   4816,   4096,   3216,   2224,   1136,
 130     3216,   4464,   4208,   3792,   3216,   2528,   1744,   880,
 131     2224,   3072,   2896,   2608,   2224,   1744,   1200,   608,
 132     1136,   1568,   1472,   1328,   1136,   880,    608,    304
 133 };
 134 #endif
 135
 136 /*****************************************************************************
 137  * pi_scan : zig-zag and alternate scan patterns
 138  *****************************************************************************/
 139 u8 pi_scan[2][64] =
 140 {
 141     { /* Zig-Zag pattern */
 142         0,1,8,16,9,2,3,10,17,24,32,25,18,11,4,5,
 143         12,19,26,33,40,48,41,34,27,20,13,6,7,14,21,28,
 144         35,42,49,56,57,50,43,36,29,22,15,23,30,37,44,51,
 145         58,59,52,45,38,31,39,46,53,60,61,54,47,55,62,63
 146     },
 147     { /* Alternate scan pattern */
 148         0,8,16,24,1,9,2,10,17,25,32,40,48,56,57,49,
 149         41,33,26,18,3,11,4,12,19,27,34,42,50,58,35,43,
 150         51,59,20,28,5,13,6,14,21,29,36,44,52,60,37,45,
 151         53,61,22,30,7,15,23,31,38,46,54,62,39,47,55,63
 152     }
 153 };
 154
 155 /*
 156  * Local inline functions.
 157  */
 158
 159 /*****************************************************************************
 160  * NextStartCode : Find the next start code
 161  *****************************************************************************/
 162 static __inline__ void NextStartCode( vpar_thread_t * p_vpar )
 163 {
 164     /* Re-align the buffer on an 8-bit boundary */
 165     RealignBits( &p_vpar->bit_stream );
 166
 167     while( ShowBits( &p_vpar->bit_stream, 24 ) != 0x01L && !p_vpar->b_die )
 168     {
 169         RemoveBits( &p_vpar->bit_stream, 8 );
 170     }
 171 }
 172
 173 /*****************************************************************************
 174  * ReferenceUpdate : Update the reference pointers when we have a new picture
 175  *****************************************************************************/
 176 static void __inline__ ReferenceUpdate( vpar_thread_t * p_vpar,
 177                                         int i_coding_type,
 178                                         picture_t * p_newref )
 179 {
 180     if( i_coding_type != B_CODING_TYPE )
 181     {
 182         if( p_vpar->sequence.p_forward != NULL )
 183             vout_UnlinkPicture( p_vpar->p_vout, p_vpar->sequence.p_forward );
 184         p_vpar->sequence.p_forward = p_vpar->sequence.p_backward;
 185         p_vpar->sequence.p_backward = p_newref;
 186         if( p_newref != NULL )
 187             vout_LinkPicture( p_vpar->p_vout, p_newref );
 188     }
 189 }
 190
 191 /*****************************************************************************
 192  * ReferenceReplace : Replace the last reference pointer when we destroy
 193  * a picture
 194  *****************************************************************************/
 195 static void __inline__ ReferenceReplace( vpar_thread_t * p_vpar,
 196                                          int i_coding_type,
 197                                          picture_t * p_newref )
 198 {
 199     if( i_coding_type != B_CODING_TYPE )
 200     {
 201         if( p_vpar->sequence.p_backward != NULL )
 202             vout_UnlinkPicture( p_vpar->p_vout, p_vpar->sequence.p_backward );
 203         p_vpar->sequence.p_backward = p_newref;
 204         if( p_newref != NULL )
 205             vout_LinkPicture( p_vpar->p_vout, p_newref );
 206     }
 207 }
 208
 209 /*****************************************************************************
 210  * LoadMatrix : Load a quantization matrix
 211  *****************************************************************************/
 212 static __inline__ void LoadMatrix( vpar_thread_t * p_vpar, quant_matrix_t * p_matrix )
 213 {
 214     int i_dummy;
 215
 216     if( !p_matrix->b_allocated )
 217     {
 218         /* Allocate a piece of memory to load the matrix. */
 219         p_matrix->pi_matrix = (int *)malloc( 64*sizeof(int) );
 220         p_matrix->b_allocated = 1;
 221     }
 222
 223     for( i_dummy = 0; i_dummy < 64; i_dummy++ )
 224     {
 225         p_matrix->pi_matrix[pi_scan[SCAN_ZIGZAG][i_dummy]]
 226              = GetBits( &p_vpar->bit_stream, 8 );
 227     }
 228
 229 #ifdef VDEC_DFT
 230     /* Discrete Fourier Transform requires the quantization matrices to
 231      * be normalized before using them. */
 232     vdec_NormQuantMatrix( p_matrix->pi_matrix );
 233 #endif
 234 }
 235
 236 /*****************************************************************************
 237  * LinkMatrix : Link a quantization matrix to another
 238  *****************************************************************************/
 239 static __inline__ void LinkMatrix( quant_matrix_t * p_matrix, int * pi_array )
 240 {
 241     int i_dummy;
 242
 243     if( p_matrix->b_allocated )
 244     {
 245         /* Deallocate the piece of memory. */
 246         free( p_matrix->pi_matrix );
 247         p_matrix->b_allocated = 0;
 248     }
 249
 250     p_matrix->pi_matrix = pi_array;
 251 }
 252
 253 /*
 254  * Exported functions.
 255  */
 256
 257 /*****************************************************************************
 258  * vpar_NextSequenceHeader : Find the next sequence header
 259  *****************************************************************************/
 260 int vpar_NextSequenceHeader( vpar_thread_t * p_vpar )
 261 {
 262     while( !p_vpar->b_die )
 263     {
 264         NextStartCode( p_vpar );
 265         if( ShowBits( &p_vpar->bit_stream, 32 ) == SEQUENCE_HEADER_CODE )
 266             return 0;
 267         RemoveBits( &p_vpar->bit_stream, 8 );
 268     }
 269     return 1;
 270 }
 271
 272 /*****************************************************************************
 273  * vpar_ParseHeader : Parse the next header
 274  *****************************************************************************/
 275 int vpar_ParseHeader( vpar_thread_t * p_vpar )
 276 {
 277     while( !p_vpar->b_die )
 278     {
 279         NextStartCode( p_vpar );
 280         switch( GetBits32( &p_vpar->bit_stream ) )
 281         {
 282         case SEQUENCE_HEADER_CODE:
 283             fprintf( stderr, "begin sequence header\n" );
 284             SequenceHeader( p_vpar );
 285             fprintf( stderr, "end sequence header\n" );
 286             return 0;
 287             break;
 288
 289         case GROUP_START_CODE:
 290             fprintf( stderr, "begin group\n" );
 291             GroupHeader( p_vpar );
 292             fprintf( stderr, "end group\n" );
 293             return 0;
 294             break;
 295
 296         case PICTURE_START_CODE:
 297             PictureHeader( p_vpar );
 298             return 0;
 299             break;
 300
 301         case SEQUENCE_END_CODE:
 302             fprintf( stderr, "sequence header end code\n" );
 303             return 1;
 304             break;
 305
 306         default:
 307         }
 308     }
 309
 310     return 0;
 311 }
 312
 313 /*
 314  * Following functions are local
 315  */
 316
 317 /*****************************************************************************
 318  * SequenceHeader : Parse the next sequence header
 319  *****************************************************************************/
 320 static void SequenceHeader( vpar_thread_t * p_vpar )
 321 {
 322 #define RESERVED    -1
 323     static float r_frame_rate_table[16] =
 324     {
 325         0.0,
 326         ((23.0*1000.0)/1001.0),
 327         24.0,
 328         25.0,
 329         ((30.0*1000.0)/1001.0),
 330         30.0,
 331         50.0,
 332         ((60.0*1000.0)/1001.0),
 333         60.0,
 334         RESERVED, RESERVED, RESERVED, RESERVED, RESERVED, RESERVED, RESERVED
 335     };
 336 #undef RESERVED
 337
 338     int i_height_save, i_width_save;
 339
 340     i_height_save = p_vpar->sequence.i_height;
 341     i_width_save = p_vpar->sequence.i_width;
 342
 343     p_vpar->sequence.i_width = GetBits( &p_vpar->bit_stream, 12 );
 344     p_vpar->sequence.i_height = GetBits( &p_vpar->bit_stream, 12 );
 345     p_vpar->sequence.i_aspect_ratio = GetBits( &p_vpar->bit_stream, 4 );
 346     p_vpar->sequence.r_frame_rate =
 347             r_frame_rate_table[ GetBits( &p_vpar->bit_stream, 4 ) ];
 348
 349     /* We don't need bit_rate_value, marker_bit, vbv_buffer_size,
 350      * constrained_parameters_flag */
 351     RemoveBits( &p_vpar->bit_stream, 30 );
 352
 353     /*
 354      * Quantization matrices
 355      */
 356     if( GetBits( &p_vpar->bit_stream, 1 ) ) /* load_intra_quantizer_matrix */
 357     {
 358         LoadMatrix( p_vpar, &p_vpar->sequence.intra_quant );
 359     }
 360     else
 361     {
 362         /* Use default matrix. */
 363         LinkMatrix( &p_vpar->sequence.intra_quant, pi_default_intra_quant );
 364     }
 365
 366     if( GetBits( &p_vpar->bit_stream, 1 ) ) /* load_non_intra_quantizer_matrix */
 367     {
 368         LoadMatrix( p_vpar, &p_vpar->sequence.nonintra_quant );
 369     }
 370     else
 371     {
 372         /* Use default matrix. */
 373         LinkMatrix( &p_vpar->sequence.nonintra_quant, pi_default_nonintra_quant );
 374     }
 375
 376     /* Unless later overwritten by a matrix extension, we have the same
 377      * matrices for luminance and chrominance. */
 378     LinkMatrix( &p_vpar->sequence.chroma_intra_quant,
 379                 p_vpar->sequence.intra_quant.pi_matrix );
 380     LinkMatrix( &p_vpar->sequence.chroma_nonintra_quant,
 381                 p_vpar->sequence.nonintra_quant.pi_matrix );
 382
 383     /*
 384      * Sequence Extension
 385      */
 386     NextStartCode( p_vpar );
 387     if( ShowBits( &p_vpar->bit_stream, 32 ) == EXTENSION_START_CODE )
 388     {
 389         int                         i_dummy;
 390         static f_chroma_pattern_t   ppf_chroma_pattern[4] =
 391                             {NULL, vpar_CodedPattern420,
 392                              vpar_CodedPattern422, vpar_CodedPattern444};
 393
 394         /* Turn the MPEG2 flag on */
 395         p_vpar->sequence.b_mpeg2 = 1;
 396
 397         /* Parse sequence_extension */
 398         RemoveBits32( &p_vpar->bit_stream );
 399         /* extension_start_code_identifier, profile_and_level_indication */
 400         RemoveBits( &p_vpar->bit_stream, 12 );
 401         p_vpar->sequence.b_progressive = GetBits( &p_vpar->bit_stream, 1 );
 402         p_vpar->sequence.i_chroma_format = GetBits( &p_vpar->bit_stream, 2 );
 403         p_vpar->sequence.pf_decode_pattern = ppf_chroma_pattern
 404                                     [p_vpar->sequence.i_chroma_format];
 405         p_vpar->sequence.i_width |= GetBits( &p_vpar->bit_stream, 2 ) << 12;
 406         p_vpar->sequence.i_height |= GetBits( &p_vpar->bit_stream, 2 ) << 12;
 407         /* bit_rate_extension, marker_bit, vbv_buffer_size_extension, low_delay */
 408         RemoveBits( &p_vpar->bit_stream, 22 );
 409         /* frame_rate_extension_n */
 410         i_dummy = GetBits( &p_vpar->bit_stream, 2 );
 411         /* frame_rate_extension_d */
 412         p_vpar->sequence.r_frame_rate *= (i_dummy + 1)
 413                                   / (GetBits( &p_vpar->bit_stream, 5 ) + 1);
 414
 415         p_vpar->sequence.pf_decode_mv = vpar_MPEG2MotionVector;
 416     }
 417     else
 418     {
 419         /* It's an MPEG-1 stream. Put adequate parameters. */
 420
 421         p_vpar->sequence.b_mpeg2 = 0;
 422         p_vpar->sequence.b_progressive = 1;
 423         p_vpar->sequence.i_chroma_format = CHROMA_420;
 424         p_vpar->sequence.pf_decode_pattern = vpar_CodedPattern420;
 425
 426         p_vpar->sequence.pf_decode_mv = vpar_MPEG1MotionVector;
 427     }
 428
 429     /* Update sizes */
 430     p_vpar->sequence.i_mb_width = (p_vpar->sequence.i_width + 15) / 16;
 431     p_vpar->sequence.i_mb_height = (p_vpar->sequence.b_progressive) ?
 432                                    (p_vpar->sequence.i_height + 15) / 16 :
 433                                    2 * (p_vpar->sequence.i_height + 31) / 32;
 434     p_vpar->sequence.i_mb_size = p_vpar->sequence.i_mb_width
 435                                         * p_vpar->sequence.i_mb_height;
 436     p_vpar->sequence.i_width = (p_vpar->sequence.i_mb_width * 16);
 437     p_vpar->sequence.i_height = (p_vpar->sequence.i_mb_height * 16);
 438     p_vpar->sequence.i_size = p_vpar->sequence.i_width
 439                                         * p_vpar->sequence.i_height;
 440
 441     /* Update chromatic information */
 442     switch( p_vpar->sequence.i_chroma_format )
 443     {
 444     case CHROMA_420:
 445         p_vpar->sequence.i_chroma_nb_blocks = 2;
 446         p_vpar->sequence.i_chroma_width = p_vpar->sequence.i_width >> 2;
 447         p_vpar->sequence.i_chroma_mb_width = 8;
 448         p_vpar->sequence.i_chroma_mb_height = 8;
 449         break;
 450
 451     case CHROMA_422:
 452         p_vpar->sequence.i_chroma_nb_blocks = 4;
 453         p_vpar->sequence.i_chroma_width = p_vpar->sequence.i_width >> 1;
 454         p_vpar->sequence.i_chroma_mb_width = 8;
 455         p_vpar->sequence.i_chroma_mb_height = 16;
 456         break;
 457
 458     case CHROMA_444:
 459         p_vpar->sequence.i_chroma_nb_blocks = 8;
 460         p_vpar->sequence.i_chroma_width = p_vpar->sequence.i_width;
 461         p_vpar->sequence.i_chroma_mb_width = 16;
 462         p_vpar->sequence.i_chroma_mb_height = 16;
 463     }
 464
 465     /* Slice Header functions */
 466     if( p_vpar->sequence.i_height <= 2800 )
 467     {
 468         if( p_vpar->sequence.i_scalable_mode != SC_DP )
 469         {
 470             p_vpar->sequence.pf_slice_header = SliceHeader00;
 471         }
 472         else
 473         {
 474             p_vpar->sequence.pf_slice_header = SliceHeader01;
 475         }
 476     }
 477     else
 478     {
 479         if( p_vpar->sequence.i_scalable_mode != SC_DP )
 480         {
 481             p_vpar->sequence.pf_slice_header = SliceHeader10;
 482         }
 483         else
 484         {
 485             p_vpar->sequence.pf_slice_header = SliceHeader11;
 486         }
 487     }
 488
 489     if(    p_vpar->sequence.i_width != i_width_save
 490         || p_vpar->sequence.i_height != i_height_save )
 491     {
 492          /* What do we do in case of a size change ??? */
 493     }
 494
 495     /* Extension and User data */
 496     ExtensionAndUserData( p_vpar );
 497 }
 498
 499 /*****************************************************************************
 500  * GroupHeader : Parse the next group of pictures header
 501  *****************************************************************************/
 502 static void GroupHeader( vpar_thread_t * p_vpar )
 503 {
 504     /* Nothing to do, we don't care. */
 505     RemoveBits( &p_vpar->bit_stream, 27 );
 506     ExtensionAndUserData( p_vpar );
 507 }
 508
 509 /*****************************************************************************
 510  * PictureHeader : Parse the next picture header
 511  *****************************************************************************/
 512 static void PictureHeader( vpar_thread_t * p_vpar )
 513 {
 514     static f_macroblock_type_t ppf_macroblock_type[5] = {NULL,
 515                                                   vpar_IMBType, vpar_PMBType,
 516                                                   vpar_BMBType, vpar_DMBType};
 517
 518     int                 i_structure;
 519     int                 i_mb_address, i_mb_base, i_mb;
 520     elem_t *            p_y, p_u, p_v;
 521     boolean_t           b_parsable;
 522     u32                 i_dummy;
 523
 524     RemoveBits( &p_vpar->bit_stream, 10 ); /* temporal_reference */
 525     p_vpar->picture.i_coding_type = GetBits( &p_vpar->bit_stream, 3 );
 526     p_vpar->picture.pf_macroblock_type = ppf_macroblock_type
 527                                          [p_vpar->picture.i_coding_type];
 528     RemoveBits( &p_vpar->bit_stream, 16 ); /* vbv_delay */
 529
 530     if( p_vpar->picture.i_coding_type == P_CODING_TYPE || p_vpar->picture.i_coding_type == B_CODING_TYPE )
 531     {
 532         p_vpar->picture.pb_full_pel_vector[0] = GetBits( &p_vpar->bit_stream, 1 );
 533         p_vpar->picture.i_forward_f_code = GetBits( &p_vpar->bit_stream, 3 );
 534     }
 535     if( p_vpar->picture.i_coding_type == B_CODING_TYPE )
 536     {
 537         p_vpar->picture.pb_full_pel_vector[1] = GetBits( &p_vpar->bit_stream, 1 );
 538         p_vpar->picture.i_backward_f_code = GetBits( &p_vpar->bit_stream, 3 );
 539     }
 540
 541     /* extra_information_picture */
 542     while( GetBits( &p_vpar->bit_stream, 1 ) )
 543     {
 544         RemoveBits( &p_vpar->bit_stream, 8 );
 545     }
 546
 547     /*
 548      * Picture Coding Extension
 549      */
 550     NextStartCode( p_vpar );
 551     if( ShowBits( &p_vpar->bit_stream, 32 ) == EXTENSION_START_CODE )
 552     {
 553         /* Parse picture_coding_extension */
 554         RemoveBits32( &p_vpar->bit_stream );
 555         /* extension_start_code_identifier */
 556         RemoveBits( &p_vpar->bit_stream, 4 );
 557
 558         p_vpar->picture.ppi_f_code[0][0] = GetBits( &p_vpar->bit_stream, 4 );
 559         p_vpar->picture.ppi_f_code[0][1] = GetBits( &p_vpar->bit_stream, 4 );
 560         p_vpar->picture.ppi_f_code[1][0] = GetBits( &p_vpar->bit_stream, 4 );
 561         p_vpar->picture.ppi_f_code[1][1] = GetBits( &p_vpar->bit_stream, 4 );
 562         p_vpar->picture.i_intra_dc_precision = GetBits( &p_vpar->bit_stream, 2 );
 563         i_structure = GetBits( &p_vpar->bit_stream, 2 );
 564         p_vpar->picture.b_top_field_first = GetBits( &p_vpar->bit_stream, 1 );
 565         p_vpar->picture.b_frame_pred_frame_dct
 566              = GetBits( &p_vpar->bit_stream, 1 );
 567         p_vpar->picture.b_concealment_mv = GetBits( &p_vpar->bit_stream, 1 );
 568         p_vpar->picture.b_q_scale_type = GetBits( &p_vpar->bit_stream, 1 );
 569         p_vpar->picture.b_intra_vlc_format = GetBits( &p_vpar->bit_stream, 1 );
 570         p_vpar->picture.b_alternate_scan = GetBits( &p_vpar->bit_stream, 1 );
 571         p_vpar->picture.b_repeat_first_field = GetBits( &p_vpar->bit_stream, 1 );
 572         /* repeat_first_field (ISO/IEC 13818-2 6.3.10 is necessary to know
 573          * the length of the picture_display_extension structure.
 574          * chroma_420_type (obsolete) */
 575         RemoveBits( &p_vpar->bit_stream, 1 );
 576         p_vpar->picture.b_progressive_frame = GetBits( &p_vpar->bit_stream, 1 );
 577
 578         /* composite_display_flag */
 579         if( GetBits( &p_vpar->bit_stream, 1 ) )
 580         {
 581             /* v_axis, field_sequence, sub_carrier, burst_amplitude,
 582              * sub_carrier_phase */
 583             RemoveBits( &p_vpar->bit_stream, 20 );
 584         }
 585     }
 586     else
 587     {
 588         /* MPEG-1 compatibility flags */
 589         p_vpar->picture.i_intra_dc_precision = 0; /* 8 bits */
 590         i_structure = FRAME_STRUCTURE;
 591         p_vpar->picture.b_frame_pred_frame_dct = 1;
 592         p_vpar->picture.b_concealment_mv = 0;
 593         p_vpar->picture.b_q_scale_type = 0;
 594         p_vpar->picture.b_intra_vlc_format = 0;
 595         p_vpar->picture.b_alternate_scan = 0; /* zigzag */
 596         p_vpar->picture.b_repeat_first_field = 0;
 597         p_vpar->picture.b_progressive_frame = 1;
 598     }
 599
 600     if( p_vpar->picture.i_current_structure &&
 601         (i_structure == FRAME_STRUCTURE ||
 602          i_structure == p_vpar->picture.i_current_structure) )
 603     {
 604         /* We don't have the second field of the buffered frame. */
 605         if( p_vpar->picture.p_picture != NULL )
 606         {
 607             ReferenceReplace( p_vpar,
 608                       p_vpar->picture.i_coding_type,
 609                       NULL );
 610
 611             for( i_mb = 0; i_mb < p_vpar->sequence.i_mb_size >> 1; i_mb++ )
 612             {
 613                 vpar_DestroyMacroblock( &p_vpar->vfifo,
 614                                         p_vpar->picture.pp_mb[i_mb] );
 615             }
 616             vout_DestroyPicture( p_vpar->p_vout, p_vpar->picture.p_picture );
 617         }
 618
 619         p_vpar->picture.i_current_structure = 0;
 620
 621         intf_DbgMsg("vpar debug: odd number of field picture.\n");
 622     }
 623
 624     if( p_vpar->picture.i_current_structure )
 625     {
 626         /* Second field of a frame. We will decode it if, and only if we
 627          * have decoded the first frame. */
 628         b_parsable = (p_vpar->picture.p_picture != NULL);
 629     }
 630     else
 631     {
 632         /* Do we have the reference pictures ? */
 633         b_parsable = !((p_vpar->picture.i_coding_type == P_CODING_TYPE) &&
 634                        (p_vpar->sequence.p_forward == NULL)) ||
 635                       ((p_vpar->picture.i_coding_type == B_CODING_TYPE) &&
 636                        (p_vpar->sequence.p_forward == NULL ||
 637                         p_vpar->sequence.p_backward == NULL));
 638
 639         if( b_parsable )
 640         {
 641             /* Does synchro say we have enough time to decode it ? */
 642             b_parsable = vpar_SynchroChoose( p_vpar,
 643                                p_vpar->picture.i_coding_type, i_structure );
 644         }
 645     }
 646
 647     if( !b_parsable )
 648     {
 649         /* Update the reference pointers. */
 650         ReferenceUpdate( p_vpar, p_vpar->picture.i_coding_type, NULL );
 651
 652         /* Warn Synchro we have trashed a picture. */
 653         vpar_SynchroTrash( p_vpar, p_vpar->picture.i_coding_type, i_structure );
 654
 655         /* Update context. */
 656         if( i_structure != FRAME_STRUCTURE )
 657             p_vpar->picture.i_current_structure = i_structure;
 658         p_vpar->picture.p_picture = NULL;
 659
 660         return;
 661     }
 662     fprintf(stderr, "begin picture\n");
 663
 664     /* OK, now we are sure we will decode the picture. */
 665 #define P_picture p_vpar->picture.p_picture
 666     p_vpar->picture.b_error = 0;
 667
 668     if( !p_vpar->picture.i_current_structure )
 669     {
 670         /* This is a new frame. Get a structure from the video_output. */
 671         P_picture = vout_CreatePicture( p_vpar->p_vout,
 672                                         99+p_vpar->sequence.i_chroma_format, /*???*/
 673                                         p_vpar->sequence.i_width,
 674                                         p_vpar->sequence.i_height,
 675                                         p_vpar->sequence.i_width*sizeof(yuv_data_t) );
 676
 677         /* Initialize values. */
 678         P_picture->date = vpar_SynchroDecode( p_vpar,
 679                                               p_vpar->picture.i_coding_type,
 680                                               i_structure );
 681         p_vpar->picture.i_l_stride = - 8 + ( p_vpar->sequence.i_width
 682                     << ( 1 - p_vpar->picture.b_frame_structure ) );
 683         p_vpar->picture.i_c_stride = -8 + ( p_vpar->sequence.i_width
 684                     << (( 1 - p_vpar->picture.b_frame_structure ) +
 685                         ( 3 - p_vpar->sequence.i_chroma_format )) );
 686
 687         /* Update the reference pointers. */
 688         ReferenceUpdate( p_vpar, p_vpar->picture.i_coding_type, P_picture );
 689     }
 690     p_vpar->picture.i_current_structure |= i_structure;
 691     p_vpar->picture.i_structure = i_structure;
 692     p_vpar->picture.b_frame_structure = (i_structure == FRAME_STRUCTURE);
 693
 694     /* Initialize picture data for decoding. */
 695     if( i_structure == BOTTOM_FIELD )
 696     {
 697         i_mb_base = p_vpar->sequence.i_mb_size >> 1;
 698         p_vpar->mb.i_l_y = 16;
 699         p_vpar->mb.i_c_y = p_vpar->sequence.i_chroma_mb_height;
 700     }
 701     else
 702     {
 703         i_mb_base = 0;
 704         p_vpar->mb.i_l_y = p_vpar->mb.i_c_y = 0;
 705     }
 706     i_mb_address = 0;
 707     p_vpar->mb.i_l_x = p_vpar->mb.i_c_x = 0;
 708
 709     /* Extension and User data. */
 710     ExtensionAndUserData( p_vpar );
 711
 712     /* Picture data (ISO/IEC 13818-2 6.2.3.7). */
 713     NextStartCode( p_vpar );
 714     while( i_mb_address+i_mb_base < p_vpar->sequence.i_mb_size
 715            && !p_vpar->picture.b_error && !p_vpar->b_die )
 716     {
 717         if( ((i_dummy = ShowBits( &p_vpar->bit_stream, 32 ))
 718                  < SLICE_START_CODE_MIN) ||
 719             (i_dummy > SLICE_START_CODE_MAX) )
 720         {
 721             intf_DbgMsg("vpar debug: premature end of picture");
 722             p_vpar->picture.b_error = 1;
 723             break;
 724         }
 725         RemoveBits32( &p_vpar->bit_stream );
 726
 727         /* Decode slice data. */
 728         p_vpar->sequence.pf_slice_header( p_vpar, &i_mb_address, i_mb_base, i_dummy & 255 );
 729     }
 730
 731     if( p_vpar->picture.b_error )
 732     {
 733         /* Trash picture. */
 734 fprintf(stderr, "Image trashee\n");
 735         for( i_mb = 0; p_vpar->picture.pp_mb[i_mb]; i_mb++ )
 736         {
 737             vpar_DestroyMacroblock( &p_vpar->vfifo, p_vpar->picture.pp_mb[i_mb] );
 738         }
 739
 740         ReferenceReplace( p_vpar, p_vpar->picture.i_coding_type, NULL );
 741         vout_DestroyPicture( p_vpar->p_vout, P_picture );
 742
 743         /* Prepare context for the next picture. */
 744         P_picture = NULL;
 745         if( p_vpar->picture.i_current_structure == FRAME_STRUCTURE )
 746             p_vpar->picture.i_current_structure = 0;
 747     }
 748     else if( p_vpar->picture.i_current_structure == FRAME_STRUCTURE )
 749     {
 750 fprintf(stderr, "Image decodee\n");
 751         /* Frame completely parsed. */
 752         P_picture->i_deccount = p_vpar->sequence.i_mb_size;
 753         for( i_mb = 0; i_mb < p_vpar->sequence.i_mb_size; i_mb++ )
 754         {
 755             vpar_DecodeMacroblock( &p_vpar->vfifo, p_vpar->picture.pp_mb[i_mb] );
 756         }
 757
 758         /* Link referenced pictures for the decoder
 759          * They are unlinked in vpar_ReleaseMacroblock() & vpar_DestroyMacroblock() */
 760         if( p_vpar->sequence.p_forward != NULL )
 761         {
 762                 vout_LinkPicture( p_vpar->p_vout, p_vpar->sequence.p_forward );
 763         }
 764         if( p_vpar->sequence.p_backward != NULL )
 765         {
 766             vout_LinkPicture( p_vpar->p_vout, p_vpar->sequence.p_backward );
 767         }
 768
 769         /* Prepare context for the next picture. */
 770         P_picture = NULL;
 771         p_vpar->picture.i_current_structure = 0;
 772     }
 773 #undef P_picture
 774 }
 775
 776 /*****************************************************************************
 777  * SliceHeader : Parse the next slice structure
 778  *****************************************************************************/
 779 static __inline__ void SliceHeader( vpar_thread_t * p_vpar,
 780                                     int * pi_mb_address, int i_mb_base,
 781                                     u32 i_vert_code )
 782 {
 783     /* DC predictors initialization table */
 784     static int              pi_dc_dct_reinit[4] = {128,256,512,1024};
 785
 786     int                     i_mb_address_save = *pi_mb_address;
 787
 788     /* slice_vertical_position_extension and priority_breakpoint already done */
 789     LoadQuantizerScale( p_vpar );
 790
 791     if( GetBits( &p_vpar->bit_stream, 1 ) )
 792     {
 793         /* intra_slice, slice_id */
 794         RemoveBits( &p_vpar->bit_stream, 8 );
 795         /* extra_information_slice */
 796         while( GetBits( &p_vpar->bit_stream, 1 ) )
 797         {
 798             RemoveBits( &p_vpar->bit_stream, 8 );
 799         }
 800     }
 801     *pi_mb_address = (i_vert_code - 1)*p_vpar->sequence.i_mb_width;
 802
 803     /* Reset DC coefficients predictors (ISO/IEC 13818-2 7.2.1). Why
 804      * does the reference decoder put 0 instead of the normative values ? */
 805     p_vpar->slice.pi_dc_dct_pred[0] = p_vpar->slice.pi_dc_dct_pred[1]
 806         = p_vpar->slice.pi_dc_dct_pred[2]
 807         = pi_dc_dct_reinit[p_vpar->picture.i_intra_dc_precision];
 808
 809     /* Reset motion vector predictors (ISO/IEC 13818-2 7.6.3.4). */
 810     memset( p_vpar->slice.pppi_pmv, 0, 8*sizeof(int) );
 811
 812     do
 813     {
 814         vpar_ParseMacroblock( p_vpar, pi_mb_address, i_mb_address_save,
 815                               i_mb_base );
 816         i_mb_address_save = *pi_mb_address;
 817     }
 818     while( ShowBits( &p_vpar->bit_stream, 23 ) && !p_vpar->b_die );
 819     NextStartCode( p_vpar );
 820 }
 821
 822 /*****************************************************************************
 823  * SliceHeaderXY : Parse the next slice structure
 824  *****************************************************************************
 825  * X = i_height > 2800 ?
 826  * Y = scalable_mode == SC_DP ?
 827  *****************************************************************************/
 828 static void SliceHeader00( vpar_thread_t * p_vpar,
 829                            int * pi_mb_address, int i_mb_base,
 830                            u32 i_vert_code )
 831 {
 832     SliceHeader( p_vpar, pi_mb_address, i_mb_base, i_vert_code );
 833 }
 834
 835 static void SliceHeader01( vpar_thread_t * p_vpar,
 836                            int * pi_mb_address, int i_mb_base,
 837                            u32 i_vert_code )
 838 {
 839     RemoveBits( &p_vpar->bit_stream, 7 ); /* priority_breakpoint */
 840     SliceHeader( p_vpar, pi_mb_address, i_mb_base, i_vert_code );
 841 }
 842
 843 static void SliceHeader10( vpar_thread_t * p_vpar,
 844                            int * pi_mb_address, int i_mb_base,
 845                            u32 i_vert_code )
 846 {
 847     i_vert_code += GetBits( &p_vpar->bit_stream, 3 ) << 7;
 848     SliceHeader( p_vpar, pi_mb_address, i_mb_base, i_vert_code );
 849 }
 850
 851 static void SliceHeader11( vpar_thread_t * p_vpar,
 852                            int * pi_mb_address, int i_mb_base,
 853                            u32 i_vert_code )
 854 {
 855     i_vert_code += GetBits( &p_vpar->bit_stream, 3 ) << 7;
 856     RemoveBits( &p_vpar->bit_stream, 7 ); /* priority_breakpoint */
 857     SliceHeader( p_vpar, pi_mb_address, i_mb_base, i_vert_code );
 858 }
 859
 860 /*****************************************************************************
 861  * ExtensionAndUserData : Parse the extension_and_user_data structure
 862  *****************************************************************************/
 863 static void ExtensionAndUserData( vpar_thread_t * p_vpar )
 864 {
 865     while( !p_vpar->b_die )
 866     {
 867         NextStartCode( p_vpar );
 868         switch( ShowBits( &p_vpar->bit_stream, 32 ) )
 869         {
 870         case EXTENSION_START_CODE:
 871             RemoveBits32( &p_vpar->bit_stream );
 872             switch( GetBits( &p_vpar->bit_stream, 4 ) )
 873             {
 874             case SEQUENCE_DISPLAY_EXTENSION_ID:
 875                 SequenceDisplayExtension( p_vpar );
 876                 break;
 877             case QUANT_MATRIX_EXTENSION_ID:
 878                 QuantMatrixExtension( p_vpar );
 879                 break;
 880             case SEQUENCE_SCALABLE_EXTENSION_ID:
 881                 SequenceScalableExtension( p_vpar );
 882                 break;
 883             case PICTURE_DISPLAY_EXTENSION_ID:
 884                 PictureDisplayExtension( p_vpar );
 885                 break;
 886             case PICTURE_SPATIAL_SCALABLE_EXTENSION_ID:
 887                 PictureSpatialScalableExtension( p_vpar );
 888                 break;
 889             case PICTURE_TEMPORAL_SCALABLE_EXTENSION_ID:
 890                 PictureTemporalScalableExtension( p_vpar );
 891                 break;
 892             case COPYRIGHT_EXTENSION_ID:
 893                 CopyrightExtension( p_vpar );
 894                 break;
 895             default:
 896             }
 897             break;
 898
 899         case USER_DATA_START_CODE:
 900             RemoveBits32( &p_vpar->bit_stream );
 901             /* Wait for the next start code */
 902             break;
 903
 904         default:
 905             return;
 906         }
 907     }
 908 }
 909
 910
 911 /*****************************************************************************
 912  * SequenceDisplayExtension : Parse the sequence_display_extension structure *
 913  *****************************************************************************/
 914
 915 static void SequenceDisplayExtension( vpar_thread_t * p_vpar )
 916 {
 917     /* We don't care sequence_display_extension. */
 918     /* video_format */
 919     RemoveBits( &p_vpar->bit_stream, 3 );
 920     if( GetBits( &p_vpar->bit_stream, 1 ) )
 921     {
 922         /* Three bytes for color_desciption */
 923         RemoveBits( &p_vpar->bit_stream, 24 );
 924     }
 925     /* display_horizontal and vertical_size and a marker_bit */
 926     RemoveBits( &p_vpar->bit_stream, 29 );
 927 }
 928
 929
 930 /*****************************************************************************
 931  * QuantMatrixExtension : Load quantization matrices for luminance           *
 932  *                        and chrominance                                    *
 933  *****************************************************************************/
 934
 935 static void QuantMatrixExtension( vpar_thread_t * p_vpar )
 936 {
 937     if( GetBits( &p_vpar->bit_stream, 1 ) )
 938     {
 939         /* Load intra_quantiser_matrix for luminance. */
 940         LoadMatrix( p_vpar, &p_vpar->sequence.intra_quant );
 941     }
 942     else
 943     {
 944         /* Use the default matrix. */
 945         LinkMatrix( &p_vpar->sequence.intra_quant,
 946                     pi_default_intra_quant );
 947     }
 948     if( GetBits( &p_vpar->bit_stream, 1 ) )
 949     {
 950         /* Load non_intra_quantiser_matrix for luminance. */
 951         LoadMatrix( p_vpar, &p_vpar->sequence.nonintra_quant );
 952     }
 953     else
 954     {
 955         /* Use the default matrix. */
 956         LinkMatrix( &p_vpar->sequence.nonintra_quant,
 957                     pi_default_nonintra_quant );
 958     }
 959     if( GetBits( &p_vpar->bit_stream, 1 ) )
 960     {
 961         /* Load intra_quantiser_matrix for chrominance. */
 962         LoadMatrix( p_vpar, &p_vpar->sequence.chroma_intra_quant );
 963     }
 964     else
 965     {
 966         /* Link the chrominance intra matrix to the luminance one. */
 967         LinkMatrix( &p_vpar->sequence.chroma_intra_quant,
 968                     p_vpar->sequence.intra_quant.pi_matrix );
 969     }
 970     if( GetBits( &p_vpar->bit_stream, 1 ) )
 971     {
 972         /* Load non_intra_quantiser_matrix for chrominance. */
 973         LoadMatrix( p_vpar, &p_vpar->sequence.chroma_nonintra_quant );
 974     }
 975     else
 976     {
 977         /* Link the chrominance intra matrix to the luminance one. */
 978         LinkMatrix( &p_vpar->sequence.chroma_intra_quant,
 979                     p_vpar->sequence.intra_quant.pi_matrix );
 980     }
 981     if( GetBits( &p_vpar->bit_stream, 1 ) )
 982     {
 983         /* Load non_intra_quantiser_matrix for chrominance. */
 984         LoadMatrix( p_vpar, &p_vpar->sequence.chroma_nonintra_quant );
 985     }
 986     else
 987     {
 988         /* Link the chrominance nonintra matrix to the luminance one. */
 989         LinkMatrix( &p_vpar->sequence.chroma_nonintra_quant,
 990                     p_vpar->sequence.nonintra_quant.pi_matrix );
 991     }
 992 }
 993
 994
 995 /*****************************************************************************
 996  * SequenceScalableExtension : Parse the sequence_scalable_extension         *
 997  *                             structure to handle scalable coding           *
 998  *****************************************************************************/
 999
1000 static void SequenceScalableExtension( vpar_thread_t * p_vpar )
1001 {
1002     /* We don't care about anything scalable except the scalable mode. */
1003     switch( p_vpar->sequence.i_scalable_mode = GetBits( &p_vpar->bit_stream, 2 ) )
1004     /* The length of the structure depends on the value of the scalable_mode */
1005     {
1006         case 1:
1007             RemoveBits32( &p_vpar->bit_stream );
1008             RemoveBits( &p_vpar->bit_stream, 21 );
1009             break;
1010         case 2:
1011             RemoveBits( &p_vpar->bit_stream, 12 );
1012             break;
1013         default:
1014             RemoveBits( &p_vpar->bit_stream, 4 );
1015     }
1016
1017 }
1018 /*****************************************************************************
1019  * PictureDisplayExtension : Parse the picture_display_extension structure   *
1020  *****************************************************************************/
1021
1022 static void PictureDisplayExtension( vpar_thread_t * p_vpar )
1023 {
1024     /* Number of frame center offset */
1025     int nb;
1026     /* I am not sure it works but it should
1027         (fewer tests than shown in §6.3.12) */
1028     nb = p_vpar->sequence.b_progressive ? p_vpar->sequence.b_progressive +
1029                                           p_vpar->picture.b_repeat_first_field +
1030                                           p_vpar->picture.b_top_field_first
1031                          : ( p_vpar->picture.b_frame_structure + 1 ) +
1032                            p_vpar->picture.b_repeat_first_field;
1033     RemoveBits( &p_vpar->bit_stream, 34 * nb );
1034 }
1035
1036
1037 /*****************************************************************************
1038  * PictureSpatialScalableExtension                                           *
1039  *****************************************************************************/
1040
1041 static void PictureSpatialScalableExtension( vpar_thread_t * p_vpar )
1042 {
1043     /* That's scalable, so we trash it */
1044     RemoveBits32( &p_vpar->bit_stream );
1045     RemoveBits( &p_vpar->bit_stream, 16 );
1046 }
1047
1048
1049 /*****************************************************************************
1050  * PictureTemporalScalableExtension                                          *
1051  *****************************************************************************/
1052
1053 static void PictureTemporalScalableExtension( vpar_thread_t * p_vpar )
1054 {
1055     /* Scalable again, trashed again */
1056     RemoveBits( &p_vpar->bit_stream, 23 );
1057 }
1058
1059
1060 /*****************************************************************************
1061  * CopyrightExtension : Keeps some legal informations                        *
1062  *****************************************************************************/
1063
1064 static void CopyrightExtension( vpar_thread_t * p_vpar )
1065 {
1066     u32     i_copyright_nb_1, i_copyright_nb_2; /* local integers */
1067     p_vpar->sequence.b_copyright_flag = GetBits( &p_vpar->bit_stream, 1 );
1068         /* A flag that says whether the copyright information is significant */
1069     p_vpar->sequence.i_copyright_id = GetBits( &p_vpar->bit_stream, 8 );
1070         /* An identifier compliant with ISO/CEI JTC 1/SC 29 */
1071     p_vpar->sequence.b_original = GetBits( &p_vpar->bit_stream, 1 );
1072         /* Reserved bits */
1073     RemoveBits( &p_vpar->bit_stream, 8 );
1074         /* The copyright_number is split in three parts */
1075         /* first part */
1076     i_copyright_nb_1 = GetBits( &p_vpar->bit_stream, 20 );
1077     RemoveBits( &p_vpar->bit_stream, 1 );
1078         /* second part */
1079     i_copyright_nb_2 = GetBits( &p_vpar->bit_stream, 22 );
1080     RemoveBits( &p_vpar->bit_stream, 1 );
1081         /* third part and sum */
1082     p_vpar->sequence.i_copyright_nb = ( (u64)i_copyright_nb_1 << 44 ) +
1083                                       ( (u64)i_copyright_nb_2 << 22 ) +
1084                                       ( (u64)GetBits( &p_vpar->bit_stream, 22 ) );
1085 }