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

   1 /*****************************************************************************
   2  * ps.c
   3  *****************************************************************************
   4  * Copyright (C) 2004 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
  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., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <stdlib.h>                                      /* malloc(), free() */
  28
  29 #include <vlc/vlc.h>
  30 #include <vlc/input.h>
  31
  32 #include "ps.h"
  33
  34 /* TODO:
  35  *  - re-add pre-scanning.
  36  *  - ...
  37  */
  38
  39 /*****************************************************************************
  40  * Module descriptor
  41  *****************************************************************************/
  42 static int  Open    ( vlc_object_t * );
  43 static void Close  ( vlc_object_t * );
  44
  45 vlc_module_begin();
  46     set_description( _("PS demuxer") );
  47     set_capability( "demux2", 1 );
  48     set_callbacks( Open, Close );
  49     add_shortcut( "ps" );
  50 vlc_module_end();
  51
  52 /*****************************************************************************
  53  * Local prototypes
  54  *****************************************************************************/
  55
  56 struct demux_sys_t
  57 {
  58     ps_track_t   tk[PS_TK_COUNT];
  59
  60     int64_t     i_scr;
  61     int         i_mux_rate;
  62 };
  63
  64 static int Demux  ( demux_t *p_demux );
  65 static int Control( demux_t *p_demux, int i_query, va_list args );
  66
  67 static int      ps_pkt_resynch( stream_t *, uint32_t *pi_code );
  68 static block_t *ps_pkt_read   ( stream_t *, uint32_t i_code );
  69
  70 /*****************************************************************************
  71  * Open
  72  *****************************************************************************/
  73 static int Open( vlc_object_t *p_this )
  74 {
  75     demux_t     *p_demux = (demux_t*)p_this;
  76     demux_sys_t *p_sys;
  77
  78     uint8_t     *p_peek;
  79
  80     if( stream_Peek( p_demux->s, &p_peek, 4 ) < 4 )
  81     {
  82         msg_Err( p_demux, "cannot peek" );
  83         return VLC_EGENERIC;
  84     }
  85
  86     if( p_peek[0] != 0 || p_peek[1] != 0 || p_peek[2] != 1 || p_peek[3] < 0xb9 )
  87     {
  88         msg_Warn( p_demux, "this does not look like an MPEG PS stream, continuing anyway" );
  89     }
  90
  91     /* Fill p_demux field */
  92     p_demux->pf_demux = Demux;
  93     p_demux->pf_control = Control;
  94     p_demux->p_sys = p_sys = malloc( sizeof( demux_sys_t ) );
  95
  96     /* Init p_sys */
  97     p_sys->i_mux_rate = 0;
  98     p_sys->i_scr      = -1;
  99
 100     ps_track_init( p_sys->tk );
 101
 102     /* TODO prescanning of ES */
 103
 104     return VLC_SUCCESS;
 105 }
 106
 107 /*****************************************************************************
 108  * Close
 109  *****************************************************************************/
 110 static void Close( vlc_object_t *p_this )
 111 {
 112     demux_t     *p_demux = (demux_t*)p_this;
 113     demux_sys_t *p_sys = p_demux->p_sys;
 114
 115     free( p_sys );
 116 }
 117
 118 /*****************************************************************************
 119  * Demux:
 120  *****************************************************************************/
 121 static int Demux( demux_t *p_demux )
 122 {
 123     demux_sys_t *p_sys = p_demux->p_sys;
 124     int i_ret;
 125     uint32_t i_code;
 126     block_t  *p_pkt;
 127
 128     i_ret = ps_pkt_resynch( p_demux->s, &i_code );
 129     if( i_ret < 0 )
 130     {
 131         return 0;
 132     }
 133     else if( i_ret == 0 )
 134     {
 135         msg_Warn( p_demux, "garbage at input" );
 136         return 1;
 137     }
 138
 139     if( ( p_pkt = ps_pkt_read( p_demux->s, i_code ) ) == NULL )
 140     {
 141         return 0;
 142     }
 143
 144     switch( i_code )
 145     {
 146         case 0x1b9:
 147             block_Release( p_pkt );
 148             break;
 149         case 0x1ba:
 150         {
 151             int i_mux_rate;
 152
 153             if( !ps_pkt_parse_pack( p_pkt, &p_sys->i_scr, &i_mux_rate ) )
 154             {
 155                 es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_sys->i_scr );
 156                 if( i_mux_rate > 0 )
 157                 {
 158                     p_sys->i_mux_rate = i_mux_rate;
 159                 }
 160             }
 161             block_Release( p_pkt );
 162             break;
 163         }
 164         case 0x1bb:
 165             if( !ps_pkt_parse_system( p_pkt, p_sys->tk ) )
 166             {
 167                 int i;
 168                 for( i = 0; i < PS_TK_COUNT; i++ )
 169                 {
 170                     ps_track_t *tk = &p_sys->tk[i];
 171
 172                     if( tk->b_seen && !tk->es && tk->fmt.i_cat != UNKNOWN_ES )
 173                     {
 174                         tk->es = es_out_Add( p_demux->out, &tk->fmt );
 175                     }
 176                 }
 177             }
 178             block_Release( p_pkt );
 179             break;
 180         case 0x1bc:
 181             /* TODO PSM */
 182             block_Release( p_pkt );
 183             break;
 184
 185         default:
 186         {
 187             int        i_id = ps_pkt_id( p_pkt );
 188             if( i_id >= 0xc0 )
 189             {
 190                 ps_track_t *tk = &p_sys->tk[PS_ID_TO_TK(i_id)];
 191
 192                 if( !tk->b_seen )
 193                 {
 194                     if( !ps_track_fill( tk, i_id ) )
 195                     {
 196                         tk->es = es_out_Add( p_demux->out, &tk->fmt );
 197                     }
 198                     tk->b_seen = VLC_TRUE;
 199                 }
 200                 if( tk->b_seen && tk->es && !ps_pkt_parse_pes( p_pkt, tk->i_skip ) )
 201                 {
 202                     es_out_Send( p_demux->out, tk->es, p_pkt );
 203                 }
 204                 else
 205                 {
 206                     block_Release( p_pkt );
 207                 }
 208             }
 209             else
 210             {
 211                 block_Release( p_pkt );
 212             }
 213             break;
 214         }
 215     }
 216     return 1;
 217 }
 218
 219 /*****************************************************************************
 220  * Control:
 221  *****************************************************************************/
 222 static int Control( demux_t *p_demux, int i_query, va_list args )
 223 {
 224     demux_sys_t *p_sys = p_demux->p_sys;
 225     double f, *pf;
 226     int64_t i64, *pi64;
 227
 228     switch( i_query )
 229     {
 230         case DEMUX_GET_POSITION:
 231             pf = (double*) va_arg( args, double* );
 232             i64 = stream_Size( p_demux->s );
 233             if( i64 > 0 )
 234             {
 235                 *pf = (double)stream_Tell( p_demux->s ) / (double)i64;
 236             }
 237             else
 238             {
 239                 *pf = 0.0;
 240             }
 241             return VLC_SUCCESS;
 242         case DEMUX_SET_POSITION:
 243             f = (double) va_arg( args, double );
 244             i64 = stream_Size( p_demux->s );
 245
 246             es_out_Control( p_demux->out, ES_OUT_RESET_PCR );
 247
 248             return stream_Seek( p_demux->s, (int64_t)(i64 * f) );
 249
 250         case DEMUX_GET_TIME:
 251             pi64 = (int64_t*)va_arg( args, int64_t * );
 252             if( p_sys->i_mux_rate > 0 )
 253             {
 254                 *pi64 = (int64_t)1000000 * ( stream_Tell( p_demux->s ) / 50 ) / p_sys->i_mux_rate;
 255                 return VLC_SUCCESS;
 256             }
 257             *pi64 = 0;
 258             return VLC_EGENERIC;
 259
 260         case DEMUX_GET_LENGTH:
 261             pi64 = (int64_t*)va_arg( args, int64_t * );
 262             if( p_sys->i_mux_rate > 0 )
 263             {
 264                 *pi64 = (int64_t)1000000 * ( stream_Size( p_demux->s ) / 50 ) / p_sys->i_mux_rate;
 265                 return VLC_SUCCESS;
 266             }
 267             *pi64 = 0;
 268             return VLC_EGENERIC;
 269
 270         case DEMUX_SET_TIME:
 271         case DEMUX_GET_FPS:
 272         default:
 273             return VLC_EGENERIC;
 274     }
 275 }
 276
 277 /*****************************************************************************
 278  * Divers:
 279  *****************************************************************************/
 280
 281 /* PSResynch: resynch on a systeme starcode
 282  *  It doesn't skip more than 512 bytes
 283  *  -1 -> error, 0 -> not synch, 1 -> ok
 284  */
 285 static int ps_pkt_resynch( stream_t *s, uint32_t *pi_code )
 286 {
 287     uint8_t *p_peek;
 288     int     i_peek;
 289     int     i_skip;
 290
 291     if( stream_Peek( s, &p_peek, 4 ) < 4 )
 292     {
 293         return -1;
 294     }
 295     if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 && p_peek[3] >= 0xb9 )
 296     {
 297         *pi_code = 0x100 | p_peek[3];
 298         return 1;
 299     }
 300
 301     if( ( i_peek = stream_Peek( s, &p_peek, 512 ) ) < 4 )
 302     {
 303         return -1;
 304     }
 305     i_skip = 0;
 306
 307     for( ;; )
 308     {
 309         if( i_peek < 4 )
 310         {
 311             break;
 312         }
 313         if( p_peek[0] == 0 && p_peek[1] == 0 && p_peek[2] == 1 && p_peek[3] >= 0xb9 )
 314         {
 315             *pi_code = 0x100 | p_peek[3];
 316             return stream_Read( s, NULL, i_skip ) == i_skip ? 1 : -1;
 317         }
 318
 319         p_peek++;
 320         i_peek--;
 321         i_skip++;
 322     }
 323     return stream_Read( s, NULL, i_skip ) == i_skip ? 0 : -1;
 324 }
 325
 326 static block_t *ps_pkt_read( stream_t *s, uint32_t i_code )
 327 {
 328     uint8_t *p_peek;
 329     int      i_peek = stream_Peek( s, &p_peek, 14 );
 330     int      i_size = ps_pkt_size( p_peek, i_peek );
 331
 332     if( i_size > 0 )
 333     {
 334         return  stream_Block( s, i_size );
 335     }
 336     return NULL;
 337 }