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

   1 /*****************************************************************************
   2  * pva.c: PVA demuxer
   3  *****************************************************************************
   4  * Copyright (C) 2004 VLC authors and VideoLAN
   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 it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * 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     p_sys = malloc( sizeof( demux_sys_t ) );
  96     if( unlikely(p_sys == NULL) )
  97         return VLC_ENOMEM;
  98
  99     /* Fill p_demux field */
 100     p_demux->pf_demux = Demux;
 101     p_demux->pf_control = Control;
 102     p_demux->p_sys = p_sys;
 103
 104     /* Register one audio and one video stream */
 105     es_format_Init( &fmt, AUDIO_ES, VLC_CODEC_MPGA );
 106     fmt.b_packetized = false;
 107     p_sys->p_audio = es_out_Add( p_demux->out, &fmt );
 108
 109     es_format_Init( &fmt, VIDEO_ES, VLC_CODEC_MPGV );
 110     fmt.b_packetized = false;
 111     p_sys->p_video = es_out_Add( p_demux->out, &fmt );
 112
 113     p_sys->i_vc    = -1;
 114     p_sys->i_ac    = -1;
 115     p_sys->p_pes   = NULL;
 116     p_sys->p_es    = NULL;
 117
 118     p_sys->b_pcr_audio = false;
 119
 120     return VLC_SUCCESS;
 121 }
 122
 123 /*****************************************************************************
 124  * Close
 125  *****************************************************************************/
 126 static void Close( vlc_object_t *p_this )
 127 {
 128     demux_t     *p_demux = (demux_t*)p_this;
 129     demux_sys_t *p_sys = p_demux->p_sys;
 130
 131     if( p_sys->p_es )  block_Release( p_sys->p_es );
 132     if( p_sys->p_pes ) block_Release( p_sys->p_pes );
 133
 134     free( p_sys );
 135 }
 136
 137
 138 /*****************************************************************************
 139  * Demux:
 140  *****************************************************************************
 141  * See http://multimedia.cx/mirror/av_format_v1.pdf
 142  *****************************************************************************/
 143 static int Demux( demux_t *p_demux )
 144 {
 145     demux_sys_t *p_sys = p_demux->p_sys;
 146
 147     const uint8_t *p_peek;
 148     int         i_size;
 149     block_t     *p_frame;
 150     int64_t     i_pts;
 151     int         i_skip;
 152
 153     if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
 154     {
 155         msg_Warn( p_demux, "eof ?" );
 156         return 0;
 157     }
 158     if( p_peek[0] != 'A' || p_peek[1] != 'V' || p_peek[4] != 0x55 )
 159     {
 160         msg_Warn( p_demux, "lost synchro" );
 161         if( ReSynch( p_demux ) )
 162         {
 163             return -1;
 164         }
 165         if( stream_Peek( p_demux->s, &p_peek, 8 ) < 8 )
 166         {
 167             msg_Warn( p_demux, "eof ?" );
 168             return 0;
 169         }
 170     }
 171
 172     i_size = GetWBE( &p_peek[6] );
 173     switch( p_peek[2] )
 174     {
 175         case 0x01:  /* VideoStream */
 176             if( p_sys->i_vc < 0 )
 177             {
 178                 msg_Dbg( p_demux, "first packet for video" );
 179             }
 180             else if( ((p_sys->i_vc + 1)&0xff) != p_peek[3] )
 181             {
 182                 msg_Dbg( p_demux, "packet lost (video)" );
 183                 if( p_sys->p_es )
 184                 {
 185                     block_ChainRelease( p_sys->p_es );
 186                     p_sys->p_es = NULL;
 187                 }
 188             }
 189             p_sys->i_vc = p_peek[3];
 190
 191             /* read the PTS and potential extra bytes TODO: make it a bit more optimised */
 192             i_pts = -1;
 193             i_skip = 8;
 194             if( p_peek[5]&0x10 )
 195             {
 196                 int i_pre = p_peek[5]&0x3;
 197
 198                 if( ( p_frame = stream_Block( p_demux->s, 8 + 4 + i_pre ) ) )
 199                 {
 200                     i_pts = GetDWBE( &p_frame->p_buffer[8] );
 201                     if( p_frame->i_buffer > 12 )
 202                     {
 203                         p_frame->p_buffer += 12;
 204                         p_frame->i_buffer -= 12;
 205                         block_ChainAppend( &p_sys->p_es, p_frame );
 206                     }
 207                     else
 208                     {
 209                         block_Release( p_frame );
 210                     }
 211                 }
 212                 i_size -= 4 + i_pre;
 213                 i_skip  = 0;
 214                 /* Set PCR */
 215                 if( ( p_frame = p_sys->p_es ) )
 216                 {
 217
 218                     if( p_frame->i_pts > VLC_TS_INVALID && !p_sys->b_pcr_audio )
 219                     {
 220                         es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_frame->i_pts);
 221                     }
 222                     es_out_Send( p_demux->out, p_sys->p_video, p_frame );
 223
 224                     p_sys->p_es = NULL;
 225                 }
 226             }
 227
 228             if( ( p_frame = stream_Block( p_demux->s, i_size + i_skip ) ) )
 229             {
 230                 p_frame->p_buffer += i_skip;
 231                 p_frame->i_buffer -= i_skip;
 232                 if( i_pts >= 0 )
 233                     p_frame->i_pts = VLC_TS_0 + i_pts * 100 / 9;
 234                 block_ChainAppend( &p_sys->p_es, p_frame );
 235             }
 236             break;
 237
 238         case 0x02:  /* MainAudioStream */
 239             if( p_sys->i_ac < 0 )
 240             {
 241                 msg_Dbg( p_demux, "first packet for audio" );
 242             }
 243             else if( ((p_sys->i_ac + 1)&0xff) != p_peek[3] )
 244             {
 245                 msg_Dbg( p_demux, "packet lost (audio)" );
 246                 if( p_sys->p_pes )
 247                 {
 248                     block_ChainRelease( p_sys->p_pes );
 249                     p_sys->p_pes = NULL;
 250                 }
 251             }
 252             p_sys->i_ac = p_peek[3];
 253
 254             if( p_peek[5]&0x10 && p_sys->p_pes )
 255             {
 256                 ParsePES( p_demux );
 257             }
 258             if( ( p_frame = stream_Block( p_demux->s, i_size + 8 ) ) )
 259             {
 260                 p_frame->p_buffer += 8;
 261                 p_frame->i_buffer -= 8;
 262                 /* XXX this a hack, some streams aren't compliant and
 263                  * don't set pes_start flag */
 264                 if( p_sys->p_pes && p_frame->i_buffer > 4 &&
 265                     p_frame->p_buffer[0] == 0x00 &&
 266                     p_frame->p_buffer[1] == 0x00 &&
 267                     p_frame->p_buffer[2] == 0x01 )
 268                 {
 269                     ParsePES( p_demux );
 270                 }
 271                 block_ChainAppend( &p_sys->p_pes, p_frame );
 272             }
 273             break;
 274
 275         default:
 276             msg_Warn( p_demux, "unknown id=0x%x", p_peek[2] );
 277             stream_Read( p_demux->s, NULL, i_size + 8 );
 278             break;
 279     }
 280     return 1;
 281 }
 282
 283 /*****************************************************************************
 284  * Control:
 285  *****************************************************************************/
 286 static int Control( demux_t *p_demux, int i_query, va_list args )
 287 {
 288     /* demux_sys_t *p_sys = p_demux->p_sys; */
 289     double f, *pf;
 290     int64_t i64;
 291     switch( i_query )
 292     {
 293         case DEMUX_GET_POSITION:
 294             if( ( i64 = stream_Size( p_demux->s ) ) > 0 )
 295             {
 296                 pf = (double*) va_arg( args, double* );
 297                 double current = stream_Tell( p_demux->s );
 298                 *pf = current / (double)i64;
 299                 return VLC_SUCCESS;
 300             }
 301             return VLC_EGENERIC;
 302
 303         case DEMUX_SET_POSITION:
 304             f = (double) va_arg( args, double );
 305             i64 = stream_Size( p_demux->s );
 306
 307             if( stream_Seek( p_demux->s, (int64_t)(i64 * f) ) || ReSynch( p_demux ) )
 308             {
 309                 return VLC_EGENERIC;
 310             }
 311             return VLC_SUCCESS;
 312
 313 #if 0
 314         case DEMUX_GET_TIME:
 315             pi64 = (int64_t*)va_arg( args, int64_t * );
 316             if( p_sys->i_time < 0 )
 317             {
 318                 *pi64 = 0;
 319                 return VLC_EGENERIC;
 320             }
 321             *pi64 = p_sys->i_time;
 322             return VLC_SUCCESS;
 323
 324 #if 0
 325         case DEMUX_GET_LENGTH:
 326             pi64 = (int64_t*)va_arg( args, int64_t * );
 327             if( p_sys->i_mux_rate > 0 )
 328             {
 329                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) / p_sys->i_mux_rate;
 330                 return VLC_SUCCESS;
 331             }
 332             *pi64 = 0;
 333             return VLC_EGENERIC;
 334
 335 #endif
 336         case DEMUX_GET_FPS:
 337             pf = (double*)va_arg( args, double * );
 338             *pf = (double)1000000.0 / (double)p_sys->i_pcr_inc;
 339             return VLC_SUCCESS;
 340 #endif
 341         case DEMUX_SET_TIME:
 342         default:
 343             return VLC_EGENERIC;
 344     }
 345 }
 346
 347 /*****************************************************************************
 348  * ReSynch:
 349  *****************************************************************************/
 350 static int ReSynch( demux_t *p_demux )
 351 {
 352     for( ;; )
 353     {
 354         const uint8_t *p_peek;
 355         int i_peek = stream_Peek( p_demux->s, &p_peek, 1024 );
 356         if( i_peek < 8 )
 357             break;
 358
 359         int i_skip = 0;
 360
 361         while( i_skip < i_peek - 5 )
 362         {
 363             if( p_peek[0] == 'A' && p_peek[1] == 'V' && p_peek[4] == 0x55 )
 364             {
 365                 if( i_skip > 0
 366                  && stream_Read( p_demux->s, NULL, i_skip ) < i_skip )
 367                     return VLC_EGENERIC;
 368                 return VLC_SUCCESS;
 369             }
 370             p_peek++;
 371             i_skip++;
 372         }
 373
 374         if( stream_Read( p_demux->s, NULL, i_skip ) < i_skip )
 375             break;
 376     }
 377
 378     return VLC_EGENERIC;
 379 }
 380
 381 static void ParsePES( demux_t *p_demux )
 382 {
 383     demux_sys_t *p_sys = p_demux->p_sys;
 384     block_t     *p_pes = p_sys->p_pes;
 385     uint8_t     hdr[30];
 386
 387     unsigned    i_skip;
 388     mtime_t     i_dts = -1;
 389     mtime_t     i_pts = -1;
 390
 391     p_sys->p_pes = NULL;
 392
 393     /* FIXME find real max size */
 394     block_ChainExtract( p_pes, hdr, 30 );
 395
 396     /* See §2.4.3.6 of ISO 13818-1 */
 397     if( hdr[0] != 0 || hdr[1] != 0 || hdr[2] != 1 )
 398     {
 399         msg_Warn( p_demux, "invalid hdr [0x%2.2x:%2.2x:%2.2x:%2.2x]",
 400                   hdr[0], hdr[1],hdr[2],hdr[3] );
 401         block_ChainRelease( p_pes );
 402         return;
 403     }
 404     // hdr[4] i_pes_size, 2 bytes
 405     // hdr[6] Marker -> original_or_copy
 406
 407     /* we assume mpeg2 PES */
 408     i_skip = hdr[8] + 9;
 409     if( hdr[7]&0x80 )    /* has pts */
 410     {
 411         i_pts = ((mtime_t)(hdr[ 9]&0x0e ) << 29)|
 412                  (mtime_t)(hdr[10] << 22)|
 413                 ((mtime_t)(hdr[11]&0xfe) << 14)|
 414                  (mtime_t)(hdr[12] << 7)|
 415                  (mtime_t)(hdr[12] >> 1);
 416
 417         if( hdr[7]&0x40 )    /* has dts */
 418         {
 419              i_dts = ((mtime_t)(hdr[14]&0x0e ) << 29)|
 420                      (mtime_t)(hdr[15] << 22)|
 421                     ((mtime_t)(hdr[16]&0xfe) << 14)|
 422                      (mtime_t)(hdr[17] << 7)|
 423                      (mtime_t)(hdr[18] >> 1);
 424         }
 425     }
 426
 427     p_pes = block_ChainGather( p_pes );
 428     if( p_pes->i_buffer <= i_skip )
 429     {
 430         block_ChainRelease( p_pes );
 431         return;
 432     }
 433
 434     p_pes->i_buffer -= i_skip;
 435     p_pes->p_buffer += i_skip;
 436
 437     if( i_dts >= 0 )
 438         p_pes->i_dts = VLC_TS_0 + i_dts * 100 / 9;
 439     if( i_pts >= 0 )
 440         p_pes->i_pts = VLC_TS_0 + i_pts * 100 / 9;
 441
 442     /* Set PCR */
 443     if( p_pes->i_pts > 0 )
 444     {
 445         es_out_Control( p_demux->out, ES_OUT_SET_PCR, (int64_t)p_pes->i_pts);
 446         p_sys->b_pcr_audio = true;
 447     }
 448     es_out_Send( p_demux->out, p_sys->p_audio, p_pes );
 449 }
 450