git.sesse.net Git - vlc/blob - modules/packetizer/mpeg4video.c

   1 /*****************************************************************************
   2  * mpeg4video.c: mpeg 4 video packetizer
   3  *****************************************************************************
   4  * Copyright (C) 2001, 2002 VideoLAN
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *          Eric Petit <titer@videolan.org>
   9  *          Gildas Bazin <gbazin@videolan.org>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  24  *****************************************************************************/
  25
  26 /*****************************************************************************
  27  * Preamble
  28  *****************************************************************************/
  29 #include <stdlib.h>                                      /* malloc(), free() */
  30
  31 #include <vlc/vlc.h>
  32 #include <vlc/decoder.h>
  33 #include <vlc/sout.h>
  34
  35 #include "vlc_bits.h"
  36
  37 /*****************************************************************************
  38  * Module descriptor
  39  *****************************************************************************/
  40 static int  Open ( vlc_object_t * );
  41 static void Close( vlc_object_t * );
  42
  43 vlc_module_begin();
  44     set_category( CAT_SOUT );
  45     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  46     set_description( _("MPEG4 video packetizer") );
  47     set_capability( "packetizer", 50 );
  48     set_callbacks( Open, Close );
  49 vlc_module_end();
  50
  51
  52 /****************************************************************************
  53  * Local prototypes
  54  ****************************************************************************/
  55 static block_t *Packetize( decoder_t *, block_t ** );
  56
  57 struct decoder_sys_t
  58 {
  59     /*
  60      * Common properties
  61      */
  62     mtime_t i_interpolated_pts;
  63     mtime_t i_interpolated_dts;
  64     mtime_t i_last_ref_pts;
  65     mtime_t i_last_time_ref;
  66     mtime_t i_time_ref;
  67     mtime_t i_last_time;
  68     mtime_t i_last_timeincr;
  69
  70     vlc_bool_t  b_vop;
  71     int         i_buffer;
  72     int         i_buffer_size;
  73     uint8_t     *p_buffer;
  74     unsigned int i_flags;
  75
  76     int         i_fps_num;
  77     int         i_fps_den;
  78     int         i_last_incr;
  79     int         i_last_incr_diff;
  80
  81     vlc_bool_t  b_frame;
  82 };
  83
  84 static int m4v_FindStartCode( uint8_t **, uint8_t * );
  85 static int m4v_VOLParse( decoder_t *, es_format_t *, uint8_t *, int );
  86 static int vlc_log2( unsigned int );
  87
  88 #define VIDEO_OBJECT_MASK                       0x01f
  89 #define VIDEO_OBJECT_LAYER_MASK                 0x00f
  90
  91 #define VIDEO_OBJECT_START_CODE                 0x100
  92 #define VIDEO_OBJECT_LAYER_START_CODE           0x120
  93 #define VISUAL_OBJECT_SEQUENCE_START_CODE       0x1b0
  94 #define VISUAL_OBJECT_SEQUENCE_END_CODE         0x1b1
  95 #define USER_DATA_START_CODE                    0x1b2
  96 #define GROUP_OF_VOP_START_CODE                 0x1b3
  97 #define VIDEO_SESSION_ERROR_CODE                0x1b4
  98 #define VISUAL_OBJECT_START_CODE                0x1b5
  99 #define VOP_START_CODE                          0x1b6
 100 #define FACE_OBJECT_START_CODE                  0x1ba
 101 #define FACE_OBJECT_PLANE_START_CODE            0x1bb
 102 #define MESH_OBJECT_START_CODE                  0x1bc
 103 #define MESH_OBJECT_PLANE_START_CODE            0x1bd
 104 #define STILL_TEXTURE_OBJECT_START_CODE         0x1be
 105 #define TEXTURE_SPATIAL_LAYER_START_CODE        0x1bf
 106 #define TEXTURE_SNR_LAYER_START_CODE            0x1c0
 107
 108 /*****************************************************************************
 109  * Open: probe the packetizer and return score
 110  *****************************************************************************/
 111 static int Open( vlc_object_t *p_this )
 112 {
 113     decoder_t     *p_dec = (decoder_t*)p_this;
 114     decoder_sys_t *p_sys;
 115
 116     switch( p_dec->fmt_in.i_codec )
 117     {
 118         case VLC_FOURCC( 'm', '4', 's', '2'):
 119         case VLC_FOURCC( 'M', '4', 'S', '2'):
 120         case VLC_FOURCC( 'm', 'p', '4', 's'):
 121         case VLC_FOURCC( 'M', 'P', '4', 'S'):
 122         case VLC_FOURCC( 'm', 'p', '4', 'v'):
 123         case VLC_FOURCC( 'D', 'I', 'V', 'X'):
 124         case VLC_FOURCC( 'd', 'i', 'v', 'x'):
 125         case VLC_FOURCC( 'X', 'V', 'I', 'D'):
 126         case VLC_FOURCC( 'X', 'v', 'i', 'D'):
 127         case VLC_FOURCC( 'x', 'v', 'i', 'd'):
 128         case VLC_FOURCC( 'D', 'X', '5', '0'):
 129         case VLC_FOURCC( 'd', 'x', '5', '0'):
 130         case VLC_FOURCC( 0x04, 0,   0,   0):
 131         case VLC_FOURCC( '3', 'I', 'V', '2'):
 132         case VLC_FOURCC( 'm', '4', 'c', 'c'):
 133         case VLC_FOURCC( 'M', '4', 'C', 'C'):
 134             break;
 135
 136         default:
 137             return VLC_EGENERIC;
 138     }
 139
 140     /* Allocate the memory needed to store the decoder's structure */
 141     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 142     {
 143         msg_Err( p_dec, "out of memory" );
 144         return VLC_EGENERIC;
 145     }
 146     memset( p_sys, 0, sizeof(decoder_sys_t) );
 147
 148     /* Setup properties */
 149     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 150     p_dec->fmt_out.i_codec = VLC_FOURCC( 'm', 'p', '4', 'v' );
 151
 152     if( p_dec->fmt_in.i_extra )
 153     {
 154         /* We have a vol */
 155         p_dec->fmt_out.i_extra = p_dec->fmt_in.i_extra;
 156         p_dec->fmt_out.p_extra = malloc( p_dec->fmt_in.i_extra );
 157         memcpy( p_dec->fmt_out.p_extra, p_dec->fmt_in.p_extra,
 158                 p_dec->fmt_in.i_extra );
 159
 160         msg_Dbg( p_dec, "opening with vol size:%d", p_dec->fmt_in.i_extra );
 161         m4v_VOLParse( p_dec, &p_dec->fmt_out,
 162                       p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 163     }
 164     else
 165     {
 166         /* No vol, we'll have to look for one later on */
 167         p_dec->fmt_out.i_extra = 0;
 168         p_dec->fmt_out.p_extra = 0;
 169     }
 170
 171     /* Set callback */
 172     p_dec->pf_packetize = Packetize;
 173
 174     return VLC_SUCCESS;
 175 }
 176
 177 /*****************************************************************************
 178  * Close: clean up the packetizer
 179  *****************************************************************************/
 180 static void Close( vlc_object_t *p_this )
 181 {
 182     decoder_t *p_dec = (decoder_t*)p_this;
 183
 184     if( p_dec->p_sys->p_buffer ) free( p_dec->p_sys->p_buffer );
 185     free( p_dec->p_sys );
 186 }
 187
 188 /****************************************************************************
 189  * Packetize: the whole thing
 190  ****************************************************************************/
 191 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 192 {
 193     decoder_sys_t *p_sys = p_dec->p_sys;
 194
 195     block_t *p_chain_out = NULL;
 196     block_t *p_block;
 197     uint8_t *p_vol = NULL;
 198     uint8_t *p_start;
 199
 200     if( !pp_block || !*pp_block ) return NULL;
 201
 202     p_block = *pp_block;
 203
 204     /* Append data */
 205     if( p_sys->i_buffer + p_block->i_buffer > p_sys->i_buffer_size )
 206     {
 207         p_sys->i_buffer_size += p_block->i_buffer + 1024;
 208         p_sys->p_buffer = realloc( p_sys->p_buffer, p_sys->i_buffer_size );
 209     }
 210     memcpy( &p_sys->p_buffer[p_sys->i_buffer], p_block->p_buffer,
 211             p_block->i_buffer );
 212     p_sys->i_buffer += p_block->i_buffer;
 213
 214     if( p_sys->i_buffer > 10*1000000 )
 215     {
 216         msg_Warn( p_dec, "reseting context" );
 217         p_sys->i_buffer = 0;
 218     }
 219
 220     /* Search vop */
 221     p_start = &p_sys->p_buffer[p_sys->i_buffer - p_block->i_buffer - 4];
 222     if( p_start < p_sys->p_buffer )
 223     {
 224         p_start = p_sys->p_buffer;
 225     }
 226     for( ;; )
 227     {
 228         if( m4v_FindStartCode( &p_start, &p_sys->p_buffer[p_sys->i_buffer] ) )
 229         {
 230             block_Release( p_block );
 231             *pp_block = NULL;
 232             return p_chain_out;
 233         }
 234         /* fprintf( stderr, "start code=0x1%2.2x\n", p_start[3] ); */
 235
 236         if( p_vol )
 237         {
 238             if( !p_dec->fmt_out.i_extra )
 239             {
 240                 /* Copy the complete VOL */
 241                 p_dec->fmt_out.i_extra = p_start - p_vol;
 242                 p_dec->fmt_out.p_extra =
 243                     realloc( p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 244                 memcpy( p_dec->fmt_out.p_extra, p_vol,
 245                         p_dec->fmt_out.i_extra );
 246                 m4v_VOLParse( p_dec, &p_dec->fmt_out,
 247                               p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 248             }
 249
 250             /* Remove VOL from the original stream */
 251             memmove( p_vol, p_start,
 252                      p_sys->i_buffer - (p_start - p_sys->p_buffer) );
 253             p_sys->i_buffer -= p_dec->fmt_out.i_extra;
 254             p_start = p_vol;
 255
 256             p_vol = NULL;
 257         }
 258         if( p_sys->b_vop )
 259         {
 260             /* Output the complete VOP we have */
 261             int     i_out = p_start - p_sys->p_buffer;
 262             block_t *p_out = block_New( p_dec, i_out );
 263
 264             /* extract data */
 265             memcpy( p_out->p_buffer, p_sys->p_buffer, i_out );
 266             if( i_out < p_sys->i_buffer )
 267             {
 268                 memmove( p_sys->p_buffer, &p_sys->p_buffer[i_out],
 269                          p_sys->i_buffer - i_out );
 270             }
 271             p_sys->i_buffer -= i_out;
 272             p_start -= i_out;
 273
 274             p_out->i_flags = p_sys->i_flags;
 275             p_out->i_pts = p_sys->i_interpolated_pts;
 276             p_out->i_dts = p_sys->i_interpolated_dts;
 277
 278             /* FIXME doesn't work when there is multiple VOP in one block */
 279             if( p_block->i_dts > p_sys->i_interpolated_dts )
 280             {
 281                 p_out->i_length = p_block->i_dts - p_sys->i_interpolated_dts;
 282             }
 283
 284             if( p_dec->fmt_out.i_extra > 0 )
 285             {
 286                 block_ChainAppend( &p_chain_out, p_out );
 287             }
 288             else
 289             {
 290                 msg_Warn( p_dec, "waiting for VOL" );
 291                 block_Release( p_out );
 292             }
 293
 294             p_sys->b_vop = VLC_FALSE;
 295         }
 296
 297         if( p_start[3] >= 0x20 && p_start[3] <= 0x2f )
 298         {
 299             /* Start of the VOL */
 300             p_vol = p_start;
 301         }
 302         else if( p_start[3] == 0xb3 )
 303         {
 304             /* GOP header */
 305         }
 306         else if( p_start[3] == 0xb6 )
 307         {
 308             /* Parse the VOP */
 309             bs_t s;
 310             int i_modulo_time_base = 0;
 311             int i_time_increment_bits;
 312             int64_t i_time_increment, i_time_ref;
 313
 314             /* FIXME: we don't actually check we received enough data to read
 315              * the VOP time increment. */
 316             bs_init( &s, &p_start[4],
 317                      p_sys->i_buffer - (p_start - p_sys->p_buffer) - 4 );
 318
 319             switch( bs_read( &s, 2 ) )
 320             {
 321                 case 0:
 322                     p_sys->i_flags = BLOCK_FLAG_TYPE_I;
 323                     break;
 324                 case 1:
 325                     p_sys->i_flags = BLOCK_FLAG_TYPE_P;
 326                     break;
 327                 case 2:
 328                     p_sys->i_flags = BLOCK_FLAG_TYPE_B;
 329                     p_sys->b_frame = VLC_TRUE;
 330                     break;
 331                 case 3: /* gni ? */
 332                     p_sys->i_flags = BLOCK_FLAG_TYPE_PB;
 333                     break;
 334             }
 335
 336             while( bs_read( &s, 1 ) ) i_modulo_time_base++;
 337             if( !bs_read1( &s ) ) continue; /* Marker */
 338
 339             /* VOP time increment */
 340             i_time_increment_bits = vlc_log2(p_dec->p_sys->i_fps_num - 1) + 1;
 341             if( i_time_increment_bits < 1 ) i_time_increment_bits = 1;
 342             i_time_increment = bs_read( &s, i_time_increment_bits );
 343
 344             /* Interpolate PTS/DTS */
 345             if( !(p_sys->i_flags & BLOCK_FLAG_TYPE_B) )
 346             {
 347                 p_sys->i_last_time_ref = p_sys->i_time_ref;
 348                 p_sys->i_time_ref +=
 349                     (i_modulo_time_base * p_dec->p_sys->i_fps_num);
 350                 i_time_ref = p_sys->i_time_ref;
 351             }
 352             else
 353             {
 354                 i_time_ref = p_sys->i_last_time_ref +
 355                     (i_modulo_time_base * p_dec->p_sys->i_fps_num);
 356             }
 357
 358             if( p_dec->p_sys->i_fps_num )
 359             p_sys->i_interpolated_pts +=
 360                 ( (i_time_ref + i_time_increment -
 361                    p_sys->i_last_time - p_sys->i_last_timeincr) *
 362                   I64C(1000000) / p_dec->p_sys->i_fps_num );
 363
 364             p_sys->i_last_time = i_time_ref;
 365             p_sys->i_last_timeincr = i_time_increment;
 366
 367             /* Correct interpolated dts when we receive a new pts/dts */
 368             if( p_block->i_pts > 0 )
 369                 p_sys->i_interpolated_pts = p_block->i_pts;
 370             if( p_block->i_dts > 0 )
 371                 p_sys->i_interpolated_dts = p_block->i_dts;
 372
 373             if( (p_sys->i_flags & BLOCK_FLAG_TYPE_B) || !p_sys->b_frame )
 374             {
 375                 /* Trivial case (DTS == PTS) */
 376
 377                 p_sys->i_interpolated_dts = p_sys->i_interpolated_pts;
 378
 379                 if( p_block->i_pts > 0 )
 380                     p_sys->i_interpolated_dts = p_block->i_pts;
 381                 if( p_block->i_dts > 0 )
 382                     p_sys->i_interpolated_dts = p_block->i_dts;
 383
 384                 p_sys->i_interpolated_pts = p_sys->i_interpolated_dts;
 385             }
 386             else
 387             {
 388                 if( p_sys->i_last_ref_pts > 0 )
 389                     p_sys->i_interpolated_dts = p_sys->i_last_ref_pts;
 390
 391                 p_sys->i_last_ref_pts = p_sys->i_interpolated_pts;
 392             }
 393
 394             p_sys->b_vop = VLC_TRUE;
 395
 396             /* Don't re-use the same PTS/DTS twice */
 397             p_block->i_pts = p_block->i_dts = 0;
 398         }
 399
 400         p_start += 4; /* Next */
 401     }
 402 }
 403
 404 /****************************************************************************
 405  * m4v_FindStartCode
 406  ****************************************************************************/
 407 static int m4v_FindStartCode( uint8_t **pp_start, uint8_t *p_end )
 408 {
 409     uint8_t *p = *pp_start;
 410
 411     /* We wait for 4+1 bytes */
 412     for( p = *pp_start; p < p_end - 5; p++ )
 413     {
 414         if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
 415         {
 416             *pp_start = p;
 417             return VLC_SUCCESS;
 418         }
 419     }
 420
 421     *pp_start = p_end;
 422     return VLC_EGENERIC;
 423 }
 424
 425
 426 /* look at ffmpeg av_log2 ;) */
 427 static int vlc_log2( unsigned int v )
 428 {
 429     int n = 0;
 430     static const int vlc_log2_table[16] =
 431     {
 432         0,0,1,1,2,2,2,2, 3,3,3,3,3,3,3,3
 433     };
 434
 435     if( v&0xffff0000 )
 436     {
 437         v >>= 16;
 438         n += 16;
 439     }
 440     if( v&0xff00 )
 441     {
 442         v >>= 8;
 443         n += 8;
 444     }
 445     if( v&0xf0 )
 446     {
 447         v >>= 4;
 448         n += 4;
 449     }
 450     n += vlc_log2_table[v];
 451
 452     return n;
 453 }
 454
 455 /* m4v_VOLParse:
 456  *  TODO:
 457  *      - support aspect ratio
 458  */
 459 static int m4v_VOLParse( decoder_t *p_dec, es_format_t *fmt,
 460                          uint8_t *p_vol, int i_vol )
 461 {
 462     bs_t s;
 463     int i_vo_type;
 464     int i_vo_ver_id;
 465     int i_ar;
 466     int i_shape;
 467
 468     for( ;; )
 469     {
 470         if( p_vol[0] == 0x00 && p_vol[1] == 0x00 &&
 471             p_vol[2] == 0x01 &&
 472             p_vol[3] >= 0x20 && p_vol[3] <= 0x2f )
 473         {
 474             break;
 475         }
 476         p_vol++;
 477         i_vol--;
 478         if( i_vol <= 4 )
 479         {
 480             return VLC_EGENERIC;
 481         }
 482     }
 483
 484     /* parse the vol */
 485     bs_init( &s, &p_vol[4], i_vol - 4 );
 486
 487     bs_skip( &s, 1 );   /* random access */
 488     i_vo_type = bs_read( &s, 8 );
 489     if( bs_read1( &s ) )
 490     {
 491         i_vo_ver_id = bs_read( &s, 4 );
 492         bs_skip( &s, 3 );
 493     }
 494     else
 495     {
 496         i_vo_ver_id = 1;
 497     }
 498     i_ar = bs_read( &s, 4 );
 499     if( i_ar == 0xf )
 500     {
 501         int i_ar_width, i_ar_height;
 502
 503         i_ar_width = bs_read( &s, 8 );
 504         i_ar_height= bs_read( &s, 8 );
 505     }
 506     if( bs_read1( &s ) )
 507     {
 508         int i_chroma_format;
 509         int i_low_delay;
 510
 511         /* vol control parameter */
 512         i_chroma_format = bs_read( &s, 2 );
 513         i_low_delay = bs_read1( &s );
 514
 515         if( bs_read1( &s ) )
 516         {
 517             bs_skip( &s, 16 );
 518             bs_skip( &s, 16 );
 519             bs_skip( &s, 16 );
 520             bs_skip( &s, 3 );
 521             bs_skip( &s, 11 );
 522             bs_skip( &s, 1 );
 523             bs_skip( &s, 16 );
 524         }
 525     }
 526     /* shape 0->RECT, 1->BIN, 2->BIN_ONLY, 3->GRAY */
 527     i_shape = bs_read( &s, 2 );
 528     if( i_shape == 3 && i_vo_ver_id != 1 )
 529     {
 530         bs_skip( &s, 4 );
 531     }
 532
 533     if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */
 534
 535     p_dec->p_sys->i_fps_num = bs_read( &s, 16 ); /* Time increment resolution*/
 536     if( !p_dec->p_sys->i_fps_num ) p_dec->p_sys->i_fps_num = 1;
 537
 538     if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */
 539
 540     if( bs_read1( &s ) )
 541     {
 542         int i_time_increment_bits =
 543             vlc_log2( p_dec->p_sys->i_fps_num - 1 ) + 1;
 544
 545         if( i_time_increment_bits < 1 ) i_time_increment_bits = 1;
 546
 547         p_dec->p_sys->i_fps_den = bs_read( &s, i_time_increment_bits );
 548     }
 549     if( i_shape == 0 )
 550     {
 551         bs_skip( &s, 1 );
 552         fmt->video.i_width = bs_read( &s, 13 );
 553         bs_skip( &s, 1 );
 554         fmt->video.i_height= bs_read( &s, 13 );
 555         bs_skip( &s, 1 );
 556     }
 557     return VLC_SUCCESS;
 558 }