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 #include <vlc/input.h>                  /* hmmm, just for INPUT_RATE_DEFAULT */
  35
  36 #include "vlc_bits.h"
  37
  38 /*****************************************************************************
  39  * Module descriptor
  40  *****************************************************************************/
  41 static int  Open ( vlc_object_t * );
  42 static void Close( vlc_object_t * );
  43
  44 vlc_module_begin();
  45     set_category( CAT_SOUT );
  46     set_subcategory( SUBCAT_SOUT_PACKETIZER );
  47     set_description( _("MPEG4 video packetizer") );
  48     set_capability( "packetizer", 50 );
  49     set_callbacks( Open, Close );
  50 vlc_module_end();
  51
  52
  53 /****************************************************************************
  54  * Local prototypes
  55  ****************************************************************************/
  56 static block_t *Packetize( decoder_t *, block_t ** );
  57
  58 struct decoder_sys_t
  59 {
  60     /*
  61      * Common properties
  62      */
  63     mtime_t i_interpolated_pts;
  64     mtime_t i_interpolated_dts;
  65     mtime_t i_last_ref_pts;
  66     mtime_t i_last_time_ref;
  67     mtime_t i_time_ref;
  68     mtime_t i_last_time;
  69     mtime_t i_last_timeincr;
  70
  71     vlc_bool_t  b_vop;
  72     int         i_buffer;
  73     int         i_buffer_size;
  74     uint8_t     *p_buffer;
  75     unsigned int i_flags;
  76
  77     int         i_fps_num;
  78     int         i_fps_den;
  79     int         i_last_incr;
  80     int         i_last_incr_diff;
  81
  82     vlc_bool_t  b_frame;
  83 };
  84
  85 static int m4v_FindStartCode( uint8_t **, uint8_t * );
  86 static int m4v_VOLParse( decoder_t *, es_format_t *, uint8_t *, int );
  87 static int vlc_log2( unsigned int );
  88
  89 #define VIDEO_OBJECT_MASK                       0x01f
  90 #define VIDEO_OBJECT_LAYER_MASK                 0x00f
  91
  92 #define VIDEO_OBJECT_START_CODE                 0x100
  93 #define VIDEO_OBJECT_LAYER_START_CODE           0x120
  94 #define VISUAL_OBJECT_SEQUENCE_START_CODE       0x1b0
  95 #define VISUAL_OBJECT_SEQUENCE_END_CODE         0x1b1
  96 #define USER_DATA_START_CODE                    0x1b2
  97 #define GROUP_OF_VOP_START_CODE                 0x1b3
  98 #define VIDEO_SESSION_ERROR_CODE                0x1b4
  99 #define VISUAL_OBJECT_START_CODE                0x1b5
 100 #define VOP_START_CODE                          0x1b6
 101 #define FACE_OBJECT_START_CODE                  0x1ba
 102 #define FACE_OBJECT_PLANE_START_CODE            0x1bb
 103 #define MESH_OBJECT_START_CODE                  0x1bc
 104 #define MESH_OBJECT_PLANE_START_CODE            0x1bd
 105 #define STILL_TEXTURE_OBJECT_START_CODE         0x1be
 106 #define TEXTURE_SPATIAL_LAYER_START_CODE        0x1bf
 107 #define TEXTURE_SNR_LAYER_START_CODE            0x1c0
 108
 109 /*****************************************************************************
 110  * Open: probe the packetizer and return score
 111  *****************************************************************************/
 112 static int Open( vlc_object_t *p_this )
 113 {
 114     decoder_t     *p_dec = (decoder_t*)p_this;
 115     decoder_sys_t *p_sys;
 116
 117     switch( p_dec->fmt_in.i_codec )
 118     {
 119         case VLC_FOURCC( 'm', '4', 's', '2'):
 120         case VLC_FOURCC( 'M', '4', 'S', '2'):
 121         case VLC_FOURCC( 'm', 'p', '4', 's'):
 122         case VLC_FOURCC( 'M', 'P', '4', 'S'):
 123         case VLC_FOURCC( 'm', 'p', '4', 'v'):
 124         case VLC_FOURCC( 'D', 'I', 'V', 'X'):
 125         case VLC_FOURCC( 'd', 'i', 'v', 'x'):
 126         case VLC_FOURCC( 'X', 'V', 'I', 'D'):
 127         case VLC_FOURCC( 'X', 'v', 'i', 'D'):
 128         case VLC_FOURCC( 'x', 'v', 'i', 'd'):
 129         case VLC_FOURCC( 'D', 'X', '5', '0'):
 130         case VLC_FOURCC( 'd', 'x', '5', '0'):
 131         case VLC_FOURCC( 0x04, 0,   0,   0):
 132         case VLC_FOURCC( '3', 'I', 'V', '2'):
 133         case VLC_FOURCC( 'm', '4', 'c', 'c'):
 134         case VLC_FOURCC( 'M', '4', 'C', 'C'):
 135             break;
 136
 137         default:
 138             return VLC_EGENERIC;
 139     }
 140
 141     /* Allocate the memory needed to store the decoder's structure */
 142     if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
 143     {
 144         msg_Err( p_dec, "out of memory" );
 145         return VLC_EGENERIC;
 146     }
 147     memset( p_sys, 0, sizeof(decoder_sys_t) );
 148
 149     /* Setup properties */
 150     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 151     p_dec->fmt_out.i_codec = VLC_FOURCC( 'm', 'p', '4', 'v' );
 152
 153     if( p_dec->fmt_in.i_extra )
 154     {
 155         /* We have a vol */
 156         p_dec->fmt_out.i_extra = p_dec->fmt_in.i_extra;
 157         p_dec->fmt_out.p_extra = malloc( p_dec->fmt_in.i_extra );
 158         memcpy( p_dec->fmt_out.p_extra, p_dec->fmt_in.p_extra,
 159                 p_dec->fmt_in.i_extra );
 160
 161         msg_Dbg( p_dec, "opening with vol size:%d", p_dec->fmt_in.i_extra );
 162         m4v_VOLParse( p_dec, &p_dec->fmt_out,
 163                       p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 164     }
 165     else
 166     {
 167         /* No vol, we'll have to look for one later on */
 168         p_dec->fmt_out.i_extra = 0;
 169         p_dec->fmt_out.p_extra = 0;
 170     }
 171
 172     /* Set callback */
 173     p_dec->pf_packetize = Packetize;
 174
 175     return VLC_SUCCESS;
 176 }
 177
 178 /*****************************************************************************
 179  * Close: clean up the packetizer
 180  *****************************************************************************/
 181 static void Close( vlc_object_t *p_this )
 182 {
 183     decoder_t *p_dec = (decoder_t*)p_this;
 184
 185     if( p_dec->p_sys->p_buffer ) free( p_dec->p_sys->p_buffer );
 186     free( p_dec->p_sys );
 187 }
 188
 189 /****************************************************************************
 190  * Packetize: the whole thing
 191  ****************************************************************************/
 192 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 193 {
 194     decoder_sys_t *p_sys = p_dec->p_sys;
 195
 196     block_t *p_chain_out = NULL;
 197     block_t *p_block;
 198     uint8_t *p_vol = NULL;
 199     uint8_t *p_start;
 200
 201     if( !pp_block || !*pp_block ) return NULL;
 202
 203     p_block = *pp_block;
 204
 205     /* Append data */
 206     if( p_sys->i_buffer + p_block->i_buffer > p_sys->i_buffer_size )
 207     {
 208         p_sys->i_buffer_size += p_block->i_buffer + 1024;
 209         p_sys->p_buffer = realloc( p_sys->p_buffer, p_sys->i_buffer_size );
 210     }
 211     memcpy( &p_sys->p_buffer[p_sys->i_buffer], p_block->p_buffer,
 212             p_block->i_buffer );
 213     p_sys->i_buffer += p_block->i_buffer;
 214
 215     if( p_sys->i_buffer > 10*1000000 )
 216     {
 217         msg_Warn( p_dec, "reseting context" );
 218         p_sys->i_buffer = 0;
 219     }
 220
 221     /* Search vop */
 222     p_start = &p_sys->p_buffer[p_sys->i_buffer - p_block->i_buffer - 4];
 223     if( p_start < p_sys->p_buffer )
 224     {
 225         p_start = p_sys->p_buffer;
 226     }
 227     for( ;; )
 228     {
 229         if( m4v_FindStartCode( &p_start, &p_sys->p_buffer[p_sys->i_buffer] ) )
 230         {
 231             block_Release( p_block );
 232             *pp_block = NULL;
 233             return p_chain_out;
 234         }
 235         /* fprintf( stderr, "start code=0x1%2.2x\n", p_start[3] ); */
 236
 237         if( p_vol )
 238         {
 239             /* Copy the complete VOL */
 240             p_dec->fmt_out.i_extra = p_start - p_vol;
 241             p_dec->fmt_out.p_extra =
 242                 realloc( p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 243             memcpy( p_dec->fmt_out.p_extra, p_vol, p_dec->fmt_out.i_extra );
 244             m4v_VOLParse( p_dec, &p_dec->fmt_out,
 245                           p_dec->fmt_out.p_extra, p_dec->fmt_out.i_extra );
 246
 247             p_vol = NULL;
 248         }
 249         if( p_sys->b_vop )
 250         {
 251             /* Output the complete VOP we have */
 252             int     i_out = p_start - p_sys->p_buffer;
 253             block_t *p_out = block_New( p_dec, i_out );
 254
 255             /* extract data */
 256             memcpy( p_out->p_buffer, p_sys->p_buffer, i_out );
 257             if( i_out < p_sys->i_buffer )
 258             {
 259                 memmove( p_sys->p_buffer, &p_sys->p_buffer[i_out],
 260                          p_sys->i_buffer - i_out );
 261             }
 262             p_sys->i_buffer -= i_out;
 263             p_start -= i_out;
 264
 265             p_out->i_flags = p_sys->i_flags;
 266             p_out->i_pts = p_sys->i_interpolated_pts;
 267             p_out->i_dts = p_sys->i_interpolated_dts;
 268
 269             /* FIXME doesn't work when there is multiple VOP in one block */
 270             if( p_block->i_dts > p_sys->i_interpolated_dts )
 271             {
 272                 p_out->i_length = p_block->i_dts - p_sys->i_interpolated_dts;
 273             }
 274
 275             if( p_dec->fmt_out.i_extra > 0 )
 276             {
 277                 block_ChainAppend( &p_chain_out, p_out );
 278             }
 279             else
 280             {
 281                 msg_Warn( p_dec, "waiting for VOL" );
 282                 block_Release( p_out );
 283             }
 284
 285             p_sys->b_vop = VLC_FALSE;
 286         }
 287
 288         if( p_start[3] >= 0x20 && p_start[3] <= 0x2f )
 289         {
 290             /* Start of the VOL */
 291             p_vol = p_start;
 292         }
 293         else if( p_start[3] == 0xb3 )
 294         {
 295             /* GOP header */
 296         }
 297         else if( p_start[3] == 0xb6 )
 298         {
 299             /* Parse the VOP */
 300             bs_t s;
 301             int i_modulo_time_base = 0;
 302             int i_time_increment_bits;
 303             int64_t i_time_increment, i_time_ref;
 304
 305             /* FIXME: we don't actually check we received enough data to read
 306              * the VOP time increment. */
 307             bs_init( &s, &p_start[4],
 308                      p_sys->i_buffer - (p_start - p_sys->p_buffer) - 4 );
 309
 310             switch( bs_read( &s, 2 ) )
 311             {
 312                 case 0:
 313                     p_sys->i_flags = BLOCK_FLAG_TYPE_I;
 314                     break;
 315                 case 1:
 316                     p_sys->i_flags = BLOCK_FLAG_TYPE_P;
 317                     break;
 318                 case 2:
 319                     p_sys->i_flags = BLOCK_FLAG_TYPE_B;
 320                     p_sys->b_frame = VLC_TRUE;
 321                     break;
 322                 case 3: /* gni ? */
 323                     p_sys->i_flags = BLOCK_FLAG_TYPE_PB;
 324                     break;
 325             }
 326
 327             while( bs_read( &s, 1 ) ) i_modulo_time_base++;
 328             if( !bs_read1( &s ) ) continue; /* Marker */
 329
 330             /* VOP time increment */
 331             i_time_increment_bits = vlc_log2(p_dec->p_sys->i_fps_num - 1) + 1;
 332             if( i_time_increment_bits < 1 ) i_time_increment_bits = 1;
 333             i_time_increment = bs_read( &s, i_time_increment_bits );
 334
 335             /* Interpolate PTS/DTS */
 336             if( !(p_sys->i_flags & BLOCK_FLAG_TYPE_B) )
 337             {
 338                 p_sys->i_last_time_ref = p_sys->i_time_ref;
 339                 p_sys->i_time_ref +=
 340                     (i_modulo_time_base * p_dec->p_sys->i_fps_num);
 341                 i_time_ref = p_sys->i_time_ref;
 342             }
 343             else
 344             {
 345                 i_time_ref = p_sys->i_last_time_ref +
 346                     (i_modulo_time_base * p_dec->p_sys->i_fps_num);
 347             }
 348
 349             if( p_dec->p_sys->i_fps_num < 5 && /* Work-around buggy streams */
 350                 p_dec->fmt_in.video.i_frame_rate > 0 &&
 351                 p_dec->fmt_in.video.i_frame_rate_base > 0 )
 352             {
 353                 p_sys->i_interpolated_pts += I64C(1000000) *
 354                     p_dec->fmt_in.video.i_frame_rate_base *
 355                     p_block->i_rate / INPUT_RATE_DEFAULT /
 356                     p_dec->fmt_in.video.i_frame_rate;
 357             }
 358             else if( p_dec->p_sys->i_fps_num )
 359                 p_sys->i_interpolated_pts +=
 360                     ( I64C(1000000) * (i_time_ref + i_time_increment -
 361                        p_sys->i_last_time - p_sys->i_last_timeincr) *
 362                       p_block->i_rate / INPUT_RATE_DEFAULT /
 363                       p_dec->p_sys->i_fps_num );
 364
 365             p_sys->i_last_time = i_time_ref;
 366             p_sys->i_last_timeincr = i_time_increment;
 367
 368             /* Correct interpolated dts when we receive a new pts/dts */
 369             if( p_block->i_pts > 0 )
 370                 p_sys->i_interpolated_pts = p_block->i_pts;
 371             if( p_block->i_dts > 0 )
 372                 p_sys->i_interpolated_dts = p_block->i_dts;
 373
 374             if( (p_sys->i_flags & BLOCK_FLAG_TYPE_B) || !p_sys->b_frame )
 375             {
 376                 /* Trivial case (DTS == PTS) */
 377
 378                 p_sys->i_interpolated_dts = p_sys->i_interpolated_pts;
 379
 380                 if( p_block->i_pts > 0 )
 381                     p_sys->i_interpolated_dts = p_block->i_pts;
 382                 if( p_block->i_dts > 0 )
 383                     p_sys->i_interpolated_dts = p_block->i_dts;
 384
 385                 p_sys->i_interpolated_pts = p_sys->i_interpolated_dts;
 386             }
 387             else
 388             {
 389                 if( p_sys->i_last_ref_pts > 0 )
 390                     p_sys->i_interpolated_dts = p_sys->i_last_ref_pts;
 391
 392                 p_sys->i_last_ref_pts = p_sys->i_interpolated_pts;
 393             }
 394
 395             p_sys->b_vop = VLC_TRUE;
 396
 397             /* Don't re-use the same PTS/DTS twice */
 398             p_block->i_pts = p_block->i_dts = 0;
 399         }
 400
 401         p_start += 4; /* Next */
 402     }
 403 }
 404
 405 /****************************************************************************
 406  * m4v_FindStartCode
 407  ****************************************************************************/
 408 static int m4v_FindStartCode( uint8_t **pp_start, uint8_t *p_end )
 409 {
 410     uint8_t *p = *pp_start;
 411
 412     /* We wait for 4+1 bytes */
 413     for( p = *pp_start; p < p_end - 5; p++ )
 414     {
 415         if( p[0] == 0 && p[1] == 0 && p[2] == 1 )
 416         {
 417             *pp_start = p;
 418             return VLC_SUCCESS;
 419         }
 420     }
 421
 422     *pp_start = p_end;
 423     return VLC_EGENERIC;
 424 }
 425
 426
 427 /* look at ffmpeg av_log2 ;) */
 428 static int vlc_log2( unsigned int v )
 429 {
 430     int n = 0;
 431     static const int vlc_log2_table[16] =
 432     {
 433         0,0,1,1,2,2,2,2, 3,3,3,3,3,3,3,3
 434     };
 435
 436     if( v&0xffff0000 )
 437     {
 438         v >>= 16;
 439         n += 16;
 440     }
 441     if( v&0xff00 )
 442     {
 443         v >>= 8;
 444         n += 8;
 445     }
 446     if( v&0xf0 )
 447     {
 448         v >>= 4;
 449         n += 4;
 450     }
 451     n += vlc_log2_table[v];
 452
 453     return n;
 454 }
 455
 456 /* m4v_VOLParse:
 457  *  TODO:
 458  *      - support aspect ratio
 459  */
 460 static int m4v_VOLParse( decoder_t *p_dec, es_format_t *fmt,
 461                          uint8_t *p_vol, int i_vol )
 462 {
 463     bs_t s;
 464     int i_vo_type;
 465     int i_vo_ver_id;
 466     int i_ar;
 467     int i_shape;
 468
 469     for( ;; )
 470     {
 471         if( p_vol[0] == 0x00 && p_vol[1] == 0x00 &&
 472             p_vol[2] == 0x01 &&
 473             p_vol[3] >= 0x20 && p_vol[3] <= 0x2f )
 474         {
 475             break;
 476         }
 477         p_vol++;
 478         i_vol--;
 479         if( i_vol <= 4 )
 480         {
 481             return VLC_EGENERIC;
 482         }
 483     }
 484
 485     /* parse the vol */
 486     bs_init( &s, &p_vol[4], i_vol - 4 );
 487
 488     bs_skip( &s, 1 );   /* random access */
 489     i_vo_type = bs_read( &s, 8 );
 490     if( bs_read1( &s ) )
 491     {
 492         i_vo_ver_id = bs_read( &s, 4 );
 493         bs_skip( &s, 3 );
 494     }
 495     else
 496     {
 497         i_vo_ver_id = 1;
 498     }
 499     i_ar = bs_read( &s, 4 );
 500     if( i_ar == 0xf )
 501     {
 502         int i_ar_width, i_ar_height;
 503
 504         i_ar_width = bs_read( &s, 8 );
 505         i_ar_height= bs_read( &s, 8 );
 506     }
 507     if( bs_read1( &s ) )
 508     {
 509         int i_chroma_format;
 510         int i_low_delay;
 511
 512         /* vol control parameter */
 513         i_chroma_format = bs_read( &s, 2 );
 514         i_low_delay = bs_read1( &s );
 515
 516         if( bs_read1( &s ) )
 517         {
 518             bs_skip( &s, 16 );
 519             bs_skip( &s, 16 );
 520             bs_skip( &s, 16 );
 521             bs_skip( &s, 3 );
 522             bs_skip( &s, 11 );
 523             bs_skip( &s, 1 );
 524             bs_skip( &s, 16 );
 525         }
 526     }
 527     /* shape 0->RECT, 1->BIN, 2->BIN_ONLY, 3->GRAY */
 528     i_shape = bs_read( &s, 2 );
 529     if( i_shape == 3 && i_vo_ver_id != 1 )
 530     {
 531         bs_skip( &s, 4 );
 532     }
 533
 534     if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */
 535
 536     p_dec->p_sys->i_fps_num = bs_read( &s, 16 ); /* Time increment resolution*/
 537     if( !p_dec->p_sys->i_fps_num ) p_dec->p_sys->i_fps_num = 1;
 538
 539     if( !bs_read1( &s ) ) return VLC_EGENERIC; /* Marker */
 540
 541     if( bs_read1( &s ) )
 542     {
 543         int i_time_increment_bits =
 544             vlc_log2( p_dec->p_sys->i_fps_num - 1 ) + 1;
 545
 546         if( i_time_increment_bits < 1 ) i_time_increment_bits = 1;
 547
 548         p_dec->p_sys->i_fps_den = bs_read( &s, i_time_increment_bits );
 549     }
 550     if( i_shape == 0 )
 551     {
 552         bs_skip( &s, 1 );
 553         fmt->video.i_width = bs_read( &s, 13 );
 554         bs_skip( &s, 1 );
 555         fmt->video.i_height= bs_read( &s, 13 );
 556         bs_skip( &s, 1 );
 557     }
 558     return VLC_SUCCESS;
 559 }