git.sesse.net Git - vlc/blob - modules/demux/pva.c

   1 /*****************************************************************************
   2  * pva.c: PVA demuxer
   3  *****************************************************************************
   4  * Copyright (C) 2004 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Laurent Aimar <fenrir@via.ecp.fr>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27
  28 #ifdef HAVE_CONFIG_H
  29 # include "config.h"
  30 #endif
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_demux.h>
  35
  36 /*****************************************************************************
  37  * Module descriptor
  38  *****************************************************************************/
  39 static int  Open    ( vlc_object_t * );
  40 static void Close  ( vlc_object_t * );
  41
  42 vlc_module_begin ()
  43     set_description( N_("PVA demuxer" ) )
  44     set_capability( "demux", 10 )
  45     set_category( CAT_INPUT )
  46     set_subcategory( SUBCAT_INPUT_DEMUX )
  47     set_callbacks( Open, Close )
  48     add_shortcut( "pva" )
  49 vlc_module_end ()
  50
  51 /*****************************************************************************
  52  * Local prototypes
  53  *****************************************************************************/
  54
  55 struct demux_sys_t
  56 {
  57     es_out_id_t *p_video;
  58     es_out_id_t *p_audio;
  59
  60     /* counter */
  61     int          i_vc;
  62     int          i_ac;
  63
  64     /* audio/video block */
  65     block_t     *p_pes; /* audio */
  66     block_t     *p_es;  /* video */
  67
  68     int64_t     b_pcr_audio;
  69 };
  70
  71 static int  Demux   ( demux_t *p_demux );
  72 static int  Control ( demux_t *p_demux, int i_query, va_list args );
  73
  74 static int  ReSynch ( demux_t * );
  75 static void ParsePES( demux_t * );
  76
  77 /*****************************************************************************
  78  * Open
  79  *****************************************************************************/
  80 static int Open( vlc_object_t *p_this )
  81 {
  82     demux_t     *p_demux = (demux_t*)p_this;
  83     demux_sys_t *p_sys;
  84     es_format_t  fmt;
  85     const uint8_t *p_peek;
  86
  87     if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 ) return VLC_EGENERIC;
  88     if( p_peek[0] != 'A' || p_peek[1] != 'V' || p_peek[4] != 0x55 )
  89     {
  90         /* In case we had forced this demuxer we try to resynch */
  91         if( !p_demux->b_force || ReSynch( p_demux ) )
  92             return VLC_EGENERIC;
  93     }
  94
  95     /* Fill p_demux field */
  96     p_demux->pf_demux = Demux;
  97     p_demux->pf_control = Control;
  98     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
  99
 100     /* Register one audio and one video stream */
 101     es_format_Init( &fmt, AUDIO_ES, VLC_CODEC_MPGA );
 102     fmt.b_packetized = false;
 103     p_sys->p_audio = es_out_Add( p_demux->out, &fmt );
 104
 105     es_format_Init( &fmt, VIDEO_ES, VLC_CODEC_MPGV );
 106     fmt.b_packetized = false;
 107     p_sys->p_video = es_out_Add( p_demux->out, &fmt );
 108
 109     p_sys->i_vc    = -1;
 110     p_sys->i_ac    = -1;
 111     p_sys->p_pes   = NULL;
 112     p_sys->p_es    = NULL;
 113
 114     p_sys->b_pcr_audio = false;
 115
 116     return VLC_SUCCESS;
 117 }
 118
 119 /*****************************************************************************
 120  * Close
 121  *****************************************************************************/
 122 static void Close( vlc_object_t *p_this )
 123 {
 124     demux_t     *p_demux = (demux_t*)p_this;
 125     demux_sys_t *p_sys = p_demux->p_sys;
 126
 127     if( p_sys->p_es )  block_Release( p_sys->p_es );
 128     if( p_sys->p_pes ) block_Release( p_sys->p_pes );
 129
 130     free( p_sys );
 131 }
 132
 133
 134 /*****************************************************************************
 135  * Demux:
 136  *****************************************************************************
 137  * See http://multimedia.cx/mirror/av_format_v1.pdf
 138  *****************************************************************************/
 139 static int Demux( demux_t *p_demux )
 140 {
 141     demux_sys_t *p_sys = p_demux->p_sys;
 142
 143     const uint8_t *p_peek;
 144     int         i_size;
 145     block_t     *p_frame;
 146     int64_t     i_pts;
 147     int         i_skip;
 148
 149     if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
 150     {
 151         msg_Warn( p_demux, "eof ?" );
 152         return 0;
 153     }
 154     if( p_peek[0] != 'A' || p_peek[1] != 'V' || p_peek[4] != 0x55 )
 155     {
 156         msg_Warn( p_demux, "lost synchro" );
 157         if( ReSynch( p_demux ) )
 158         {
 159             return -1;
 160         }
 161         if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
 162         {
 163             msg_Warn( p_demux, "eof ?" );
 164             return 0;
 165         }
 166     }
 167
 168     i_size = GetWBE( &p_peek[6] );
 169     switch( p_peek[2] )
 170     {
 171         case 0x01:  /* VideoStream */
 172             if( p_sys->i_vc < 0 )
 173             {
 174                 msg_Dbg( p_demux, "first packet for video" );
 175             }
 176             else if( ((p_sys->i_vc + 1)&0xff) != p_peek[3] )
 177             {
 178                 msg_Dbg( p_demux, "packet lost (video)" );
 179                 if( p_sys->p_es )
 180                 {
 181                     block_ChainRelease( p_sys->p_es );
 182                     p_sys->p_es = NULL;
 183                 }
 184             }
 185             p_sys->i_vc = p_peek[3];
 186
 187             /* read the PTS and potential extra bytes TODO: make it a bit more optimised */
 188             i_pts = -1;
 189             i_skip = 8;
 190             if( p_peek[5]&0x10 )
 191             {
 192                 int i_pre = p_peek[5]&0x3;
 193
 194                 if( ( p_frame = stream_Block( p_demux->s, 8 + 4 + i_pre ) ) )
 195                 {
 196                     i_pts = GetDWBE( &p_frame->p_buffer[8] );
 197                     if( p_frame->i_buffer > 12 )
 198                     {
 199                         p_frame->p_buffer += 12;
 200                         p_frame->i_buffer -= 12;
 201                         block_ChainAppend( &p_sys->p_es, p_frame );
 202                     }
 203                     else
 204                     {
 205                         block_Release( p_frame );
 206                     }
 207                 }
 208                 i_size -= 4 + i_pre;
 209                 i_skip  = 0;
 210                 /* Set PCR */
 211                 if( ( p_frame = p_sys->p_es ) )
 212                 {
 213
 214                     if( p_frame->i_pts > VLC_TS_INVALID && !p_sys->b_pcr_audio )
 215                     {
 216                         es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_frame->i_pts);
 217                     }
 218                     es_out_Send( p_demux->out, p_sys->p_video, p_frame );
 219
 220                     p_sys->p_es = NULL;
 221                 }
 222             }
 223
 224             if( ( p_frame = stream_Block( p_demux->s, i_size + i_skip ) ) )
 225             {
 226                 p_frame->p_buffer += i_skip;
 227                 p_frame->i_buffer -= i_skip;
 228                 if( i_pts >= 0 )
 229                     p_frame->i_pts = VLC_TS_0 + i_pts * 100 / 9;
 230                 block_ChainAppend( &p_sys->p_es, p_frame );
 231             }
 232             break;
 233
 234         case 0x02:  /* MainAudioStream */
 235             if( p_sys->i_ac < 0 )
 236             {
 237                 msg_Dbg( p_demux, "first packet for audio" );
 238             }
 239             else if( ((p_sys->i_ac + 1)&0xff) != p_peek[3] )
 240             {
 241                 msg_Dbg( p_demux, "packet lost (audio)" );
 242                 if( p_sys->p_pes )
 243                 {
 244                     block_ChainRelease( p_sys->p_pes );
 245                     p_sys->p_pes = NULL;
 246                 }
 247             }
 248             p_sys->i_ac = p_peek[3];
 249
 250             if( p_peek[5]&0x10 && p_sys->p_pes )
 251             {
 252                 ParsePES( p_demux );
 253             }
 254             if( ( p_frame = stream_Block( p_demux->s, i_size + 8 ) ) )
 255             {
 256                 p_frame->p_buffer += 8;
 257                 p_frame->i_buffer -= 8;
 258                 /* XXX this a hack, some streams aren't compliant and
 259                  * don't set pes_start flag */
 260                 if( p_sys->p_pes && p_frame->i_buffer > 4 &&
 261                     p_frame->p_buffer[0] == 0x00 &&
 262                     p_frame->p_buffer[1] == 0x00 &&
 263                     p_frame->p_buffer[2] == 0x01 )
 264                 {
 265                     ParsePES( p_demux );
 266                 }
 267                 block_ChainAppend( &p_sys->p_pes, p_frame );
 268             }
 269             break;
 270
 271         default:
 272             msg_Warn( p_demux, "unknown id=0x%x", p_peek[2] );
 273             stream_Read( p_demux->s, NULL, i_size + 8 );
 274             break;
 275     }
 276     return 1;
 277 }
 278
 279 /*****************************************************************************
 280  * Control:
 281  *****************************************************************************/
 282 static int Control( demux_t *p_demux, int i_query, va_list args )
 283 {
 284     /* demux_sys_t *p_sys = p_demux->p_sys; */
 285     double f, *pf;
 286     int64_t i64;
 287     switch( i_query )
 288     {
 289         case DEMUX_GET_POSITION:
 290             if( ( i64 = stream_Size( p_demux->s ) ) > 0 )
 291             {
 292                 pf = (double*) va_arg( args, double* );
 293                 double current = stream_Tell( p_demux->s );
 294                 *pf = current / (double)i64;
 295                 return VLC_SUCCESS;
 296             }
 297             return VLC_EGENERIC;
 298
 299         case DEMUX_SET_POSITION:
 300             f = (double) va_arg( args, double );
 301             i64 = stream_Size( p_demux->s );
 302
 303             if( stream_Seek( p_demux->s, (int64_t)(i64 * f) ) || ReSynch( p_demux ) )
 304             {
 305                 return VLC_EGENERIC;
 306             }
 307             return VLC_SUCCESS;
 308
 309 #if 0
 310         case DEMUX_GET_TIME:
 311             pi64 = (int64_t*)va_arg( args, int64_t * );
 312             if( p_sys->i_time < 0 )
 313             {
 314                 *pi64 = 0;
 315                 return VLC_EGENERIC;
 316             }
 317             *pi64 = p_sys->i_time;
 318             return VLC_SUCCESS;
 319
 320 #if 0
 321         case DEMUX_GET_LENGTH:
 322             pi64 = (int64_t*)va_arg( args, int64_t * );
 323             if( p_sys->i_mux_rate > 0 )
 324             {
 325                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) / p_sys->i_mux_rate;
 326                 return VLC_SUCCESS;
 327             }
 328             *pi64 = 0;
 329             return VLC_EGENERIC;
 330
 331 #endif
 332         case DEMUX_GET_FPS:
 333             pf = (double*)va_arg( args, double * );
 334             *pf = (double)1000000.0 / (double)p_sys->i_pcr_inc;
 335             return VLC_SUCCESS;
 336 #endif
 337         case DEMUX_SET_TIME:
 338         default:
 339             return VLC_EGENERIC;
 340     }
 341 }
 342
 343 /*****************************************************************************
 344  * ReSynch:
 345  *****************************************************************************/
 346 static int ReSynch( demux_t *p_demux )
 347 {
 348     const uint8_t *p_peek;
 349     int      i_skip;
 350     int      i_peek;
 351
 352     while( vlc_object_alive (p_demux) )
 353     {
 354         if( ( i_peek = stream_Peek( p_demux->s, &p_peek, 1024 ) ) < 8 )
 355         {
 356             return VLC_EGENERIC;
 357         }
 358         i_skip = 0;
 359
 360         while( i_skip < i_peek - 5 )
 361         {
 362             if( p_peek[0] == 'A' && p_peek[1] == 'V' && p_peek[4] == 0x55 )
 363             {
 364                 if( i_skip > 0 )
 365                 {
 366                     stream_Read( p_demux->s, NULL, i_skip );
 367                 }
 368                 return VLC_SUCCESS;
 369             }
 370             p_peek++;
 371             i_skip++;
 372         }
 373
 374         stream_Read( p_demux->s, NULL, i_skip );
 375     }
 376
 377     return VLC_EGENERIC;
 378 }
 379
 380 static void ParsePES( demux_t *p_demux )
 381 {
 382     demux_sys_t *p_sys = p_demux->p_sys;
 383     block_t     *p_pes = p_sys->p_pes;
 384     uint8_t     hdr[30];
 385
 386     unsigned    i_skip;
 387     mtime_t     i_dts = -1;
 388     mtime_t     i_pts = -1;
 389
 390     p_sys->p_pes = NULL;
 391
 392     /* FIXME find real max size */
 393     block_ChainExtract( p_pes, hdr, 30 );
 394
 395     /* See §2.4.3.6 of ISO 13818-1 */
 396     if( hdr[0] != 0 || hdr[1] != 0 || hdr[2] != 1 )
 397     {
 398         msg_Warn( p_demux, "invalid hdr [0x%2.2x:%2.2x:%2.2x:%2.2x]",
 399                   hdr[0], hdr[1],hdr[2],hdr[3] );
 400         block_ChainRelease( p_pes );
 401         return;
 402     }
 403     // hdr[4] i_pes_size, 2 bytes
 404     // hdr[6] Marker -> original_or_copy
 405
 406     /* we assume mpeg2 PES */
 407     i_skip = hdr[8] + 9;
 408     if( hdr[7]&0x80 )    /* has pts */
 409     {
 410         i_pts = ((mtime_t)(hdr[ 9]&0x0e ) << 29)|
 411                  (mtime_t)(hdr[10] << 22)|
 412                 ((mtime_t)(hdr[11]&0xfe) << 14)|
 413                  (mtime_t)(hdr[12] << 7)|
 414                  (mtime_t)(hdr[12] >> 1);
 415
 416         if( hdr[7]&0x40 )    /* has dts */
 417         {
 418              i_dts = ((mtime_t)(hdr[14]&0x0e ) << 29)|
 419                      (mtime_t)(hdr[15] << 22)|
 420                     ((mtime_t)(hdr[16]&0xfe) << 14)|
 421                      (mtime_t)(hdr[17] << 7)|
 422                      (mtime_t)(hdr[18] >> 1);
 423         }
 424     }
 425
 426     p_pes = block_ChainGather( p_pes );
 427     if( p_pes->i_buffer <= i_skip )
 428     {
 429         block_ChainRelease( p_pes );
 430         return;
 431     }
 432
 433     p_pes->i_buffer -= i_skip;
 434     p_pes->p_buffer += i_skip;
 435
 436     if( i_dts >= 0 )
 437         p_pes->i_dts = VLC_TS_0 + i_dts * 100 / 9;
 438     if( i_pts >= 0 )
 439         p_pes->i_pts = VLC_TS_0 + i_pts * 100 / 9;
 440
 441     /* Set PCR */
 442     if( p_pes->i_pts > 0 )
 443     {
 444         es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_pes->i_pts);
 445         p_sys->b_pcr_audio = true;
 446     }
 447     es_out_Send( p_demux->out, p_sys->p_audio, p_pes );
 448 }
 449