git.sesse.net Git - vlc/blob - modules/codec/libmpeg2.c

   1 /*****************************************************************************
   2  * libmpeg2.c: mpeg2 video decoder module making use of libmpeg2.
   3  *****************************************************************************
   4  * Copyright (C) 1999-2001 VideoLAN
   5  * $Id: libmpeg2.c,v 1.9 2003/04/14 22:22:32 massiot Exp $
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   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 <vlc/vlc.h>
  28 #include <vlc/vout.h>
  29 #include <vlc/input.h>
  30 #include <vlc/decoder.h>
  31
  32 #include <stdlib.h>                                      /* malloc(), free() */
  33 #include <string.h>                                    /* memcpy(), memset() */
  34
  35 #include <mpeg2dec/mpeg2.h>
  36
  37 #include "vout_synchro.h"
  38
  39 /* Aspect ratio (ISO/IEC 13818-2 section 6.3.3, table 6-3) */
  40 #define AR_SQUARE_PICTURE       1                           /* square pixels */
  41 #define AR_3_4_PICTURE          2                        /* 3:4 picture (TV) */
  42 #define AR_16_9_PICTURE         3              /* 16:9 picture (wide screen) */
  43 #define AR_221_1_PICTURE        4                  /* 2.21:1 picture (movie) */
  44
  45 /*****************************************************************************
  46  * dec_thread_t : libmpeg2 decoder thread descriptor
  47  *****************************************************************************/
  48 typedef struct dec_thread_t
  49 {
  50     /*
  51      * libmpeg2 properties
  52      */
  53     mpeg2dec_t          *p_mpeg2dec;
  54     const mpeg2_info_t  *p_info;
  55
  56     /*
  57      * Input properties
  58      */
  59     decoder_fifo_t   *p_fifo;                  /* stores the PES stream data */
  60     pes_packet_t     *p_pes;                  /* current PES we are decoding */
  61     mtime_t          i_pts;
  62     mtime_t          i_previous_pts;
  63     mtime_t          i_current_pts;
  64     mtime_t          i_period_remainder;
  65     int              i_current_rate;
  66     picture_t *      p_picture_to_destroy;
  67
  68     /*
  69      * Output properties
  70      */
  71     vout_thread_t *p_vout;
  72     vout_synchro_t *p_synchro;
  73
  74 } dec_thread_t;
  75
  76 /*****************************************************************************
  77  * Local prototypes
  78  *****************************************************************************/
  79 static int  OpenDecoder  ( vlc_object_t * );
  80 static int  RunDecoder   ( decoder_fifo_t * );
  81 static void CloseDecoder ( dec_thread_t * );
  82
  83 static picture_t *GetNewPicture( dec_thread_t *, uint8_t ** );
  84
  85 /*****************************************************************************
  86  * Module descriptor
  87  *****************************************************************************/
  88 vlc_module_begin();
  89     set_description( _("MPEG I/II video decoder (using libmpeg2)") );
  90     set_capability( "decoder", 40 );
  91     set_callbacks( OpenDecoder, NULL );
  92     add_shortcut( "libmpeg2" );
  93 vlc_module_end();
  94
  95 /*****************************************************************************
  96  * OpenDecoder: probe the decoder and return score
  97  *****************************************************************************/
  98 static int OpenDecoder( vlc_object_t *p_this )
  99 {
 100     decoder_fifo_t *p_fifo = (decoder_fifo_t*) p_this;
 101
 102     if( p_fifo->i_fourcc != VLC_FOURCC('m','p','g','v') )
 103     {
 104         return VLC_EGENERIC;
 105     }
 106
 107     p_fifo->pf_run = RunDecoder;
 108     return VLC_SUCCESS;
 109 }
 110
 111 /*****************************************************************************
 112  * RunDecoder: the libmpeg2 decoder
 113  *****************************************************************************/
 114 static int RunDecoder( decoder_fifo_t *p_fifo )
 115 {
 116     dec_thread_t    *p_dec;
 117     data_packet_t   *p_data = NULL;
 118     mpeg2_state_t   state;
 119     picture_t       *p_pic;
 120     int             i_aspect, i_chroma;
 121
 122     /* Allocate the memory needed to store the thread's structure */
 123     if( (p_dec = (dec_thread_t *)malloc (sizeof(dec_thread_t)) )
 124         == NULL)
 125     {
 126         msg_Err( p_fifo, "out of memory" );
 127         goto error;
 128     }
 129
 130     /* Initialize the thread properties */
 131     memset( p_dec, 0, sizeof(dec_thread_t) );
 132     p_dec->p_fifo     = p_fifo;
 133     p_dec->p_pes      = NULL;
 134     p_dec->p_vout     = NULL;
 135     p_dec->p_mpeg2dec = NULL;
 136     p_dec->p_info     = NULL;
 137     p_dec->i_pts      = mdate() + DEFAULT_PTS_DELAY;
 138     p_dec->i_current_pts  = 0;
 139     p_dec->i_previous_pts = 0;
 140     p_dec->i_period_remainder = 0;
 141     p_dec->p_picture_to_destroy = NULL;
 142
 143     /* Initialize decoder */
 144     p_dec->p_mpeg2dec = mpeg2_init();
 145     if( p_dec->p_mpeg2dec == NULL)
 146         goto error;
 147
 148     p_dec->p_info = mpeg2_info( p_dec->p_mpeg2dec );
 149
 150     /* libmpeg2 decoder thread's main loop */
 151     while( (!p_dec->p_fifo->b_die) && (!p_dec->p_fifo->b_error) )
 152     {
 153         state = mpeg2_parse( p_dec->p_mpeg2dec );
 154
 155         switch( state )
 156         {
 157         case STATE_BUFFER:
 158             /* Feed libmpeg2 a data packet at a time */
 159             if( p_data == NULL )
 160             {
 161                 /* Get the next PES */
 162                 if( p_dec->p_pes )
 163                     input_DeletePES( p_dec->p_fifo->p_packets_mgt,
 164                                      p_dec->p_pes );
 165
 166                 input_ExtractPES( p_dec->p_fifo, &p_dec->p_pes );
 167                 if( !p_dec->p_pes )
 168                 {
 169                     p_dec->p_fifo->b_error = 1;
 170                     break;
 171                 }
 172
 173                 if( p_dec->p_pes->b_discontinuity )
 174                 {
 175                     vout_SynchroReset( p_dec->p_synchro );
 176                     if ( p_dec->p_info->current_fbuf != NULL )
 177                         p_dec->p_picture_to_destroy
 178                             = p_dec->p_info->current_fbuf->id;
 179                 }
 180
 181                 if( p_dec->p_pes->i_pts )
 182                 {
 183                     mpeg2_pts( p_dec->p_mpeg2dec,
 184                                (uint32_t)p_dec->p_pes->i_pts );
 185                     p_dec->i_previous_pts = p_dec->i_current_pts;
 186                     p_dec->i_current_pts = p_dec->p_pes->i_pts;
 187                 }
 188
 189                 p_dec->i_current_rate = p_dec->p_pes->i_rate;
 190                 p_data = p_dec->p_pes->p_first;
 191             }
 192
 193             if( p_data != NULL )
 194             {
 195                 mpeg2_buffer( p_dec->p_mpeg2dec,
 196                               p_data->p_payload_start,
 197                               p_data->p_payload_end );
 198
 199                 p_data = p_data->p_next;
 200             }
 201             break;
 202
 203         case STATE_SEQUENCE:
 204         {
 205             /* Initialize video output */
 206             uint8_t *buf[3];
 207             buf[0] = buf[1] = buf[2] = NULL;
 208
 209             /* Check whether the input gives a particular aspect ratio */
 210             if( p_dec->p_fifo->p_demux_data
 211                 && ( *(int*)(p_dec->p_fifo->p_demux_data) & 0x7 ) )
 212             {
 213                 i_aspect = *(int*)(p_dec->p_fifo->p_demux_data);
 214                 switch( i_aspect )
 215                 {
 216                 case AR_3_4_PICTURE:
 217                     i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;
 218                     break;
 219                 case AR_16_9_PICTURE:
 220                     i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;
 221                     break;
 222                 case AR_221_1_PICTURE:
 223                     i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;
 224                     break;
 225                 case AR_SQUARE_PICTURE:
 226                 default:
 227                     i_aspect = VOUT_ASPECT_FACTOR *
 228                                    p_dec->p_info->sequence->width /
 229                                    p_dec->p_info->sequence->height;
 230                     break;
 231                 }
 232             }
 233             else
 234             {
 235                 /* Use the value provided in the MPEG sequence header */
 236                 i_aspect = ((uint64_t)p_dec->p_info->sequence->width) *
 237                     p_dec->p_info->sequence->pixel_width * VOUT_ASPECT_FACTOR /
 238                     p_dec->p_info->sequence->height /
 239                     p_dec->p_info->sequence->pixel_height;
 240             }
 241
 242             i_chroma = VLC_FOURCC('Y','V','1','2');
 243
 244             p_dec->p_vout = vout_Request( p_dec->p_fifo, p_dec->p_vout,
 245                                           p_dec->p_info->sequence->width,
 246                                           p_dec->p_info->sequence->height,
 247                                           i_chroma, i_aspect );
 248
 249             mpeg2_custom_fbuf( p_dec->p_mpeg2dec, 1 );
 250
 251             /* Set the first 2 reference frames */
 252             mpeg2_set_buf( p_dec->p_mpeg2dec, buf, NULL );
 253             mpeg2_set_buf( p_dec->p_mpeg2dec, buf, NULL );
 254
 255             p_dec->p_synchro = vout_SynchroInit( p_dec->p_fifo, p_dec->p_vout,
 256                 1000000 * 27 / p_dec->p_info->sequence->frame_period * 1001 );
 257         }
 258         break;
 259
 260         case STATE_PICTURE:
 261         {
 262             uint8_t *buf[3];
 263             buf[0] = buf[1] = buf[2] = NULL;
 264
 265             vout_SynchroNewPicture( p_dec->p_synchro,
 266                 p_dec->p_info->current_picture->flags & PIC_MASK_CODING_TYPE,
 267                 p_dec->p_info->current_picture->nb_fields,
 268                 (p_dec->p_info->current_picture->flags & PIC_FLAG_PTS) ?
 269                     ( (p_dec->p_info->current_picture->pts ==
 270                                 (uint32_t)p_dec->i_current_pts) ?
 271                               p_dec->i_current_pts : p_dec->i_previous_pts ) : 0,
 272                 0,
 273                 p_dec->i_current_rate );
 274
 275             if ( !vout_SynchroChoose( p_dec->p_synchro,
 276                 p_dec->p_info->current_picture->flags & PIC_MASK_CODING_TYPE ) )
 277             {
 278                 mpeg2_skip( p_dec->p_mpeg2dec, 1 );
 279                 vout_SynchroTrash( p_dec->p_synchro );
 280                 mpeg2_set_buf( p_dec->p_mpeg2dec, buf, NULL );
 281             }
 282             else
 283             {
 284                 mpeg2_skip( p_dec->p_mpeg2dec, 0 );
 285                 vout_SynchroDecode( p_dec->p_synchro );
 286                 if( (p_pic = GetNewPicture( p_dec, buf )) == NULL ) break;
 287                 mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );
 288             }
 289         }
 290         /* pass-through */
 291
 292         case STATE_END:
 293             if( p_dec->p_info->display_fbuf
 294                 && p_dec->p_info->display_fbuf->id )
 295             {
 296                 p_pic = (picture_t *)p_dec->p_info->display_fbuf->id;
 297
 298                 if ( p_pic != NULL )
 299                 {
 300                     if ( p_dec->p_picture_to_destroy != p_pic )
 301                     {
 302                         vout_SynchroEnd( p_dec->p_synchro,
 303                             p_dec->p_info->display_picture->flags
 304                              & PIC_MASK_CODING_TYPE,
 305                             0 );
 306                         vout_DatePicture( p_dec->p_vout, p_pic,
 307                             vout_SynchroDate( p_dec->p_synchro ) );
 308                         vout_DisplayPicture( p_dec->p_vout, p_pic );
 309                     }
 310                     else
 311                     {
 312                         p_dec->p_picture_to_destroy = NULL;
 313                         vout_SynchroEnd( p_dec->p_synchro,
 314                             p_dec->p_info->display_picture->flags
 315                              & PIC_MASK_CODING_TYPE,
 316                             1 );
 317                         vout_DestroyPicture( p_dec->p_vout, p_pic );
 318                     }
 319                 }
 320                 if( p_dec->p_info->discard_fbuf &&
 321                     p_dec->p_info->discard_fbuf->id )
 322                 {
 323                     vout_UnlinkPicture( p_dec->p_vout, p_pic );
 324                 }
 325             }
 326             break;
 327
 328         case STATE_INVALID:
 329             msg_Warn( p_dec->p_fifo, "Received STATE_INVALID" );
 330             break;
 331
 332         default:
 333             break;
 334         }
 335     }
 336
 337     /* If b_error is set, the libmpeg2 decoder thread enters the error loop */
 338     if( p_dec->p_fifo->b_error )
 339     {
 340         DecoderError( p_dec->p_fifo );
 341     }
 342
 343     /* End of the libmpeg2 decoder thread */
 344     CloseDecoder( p_dec );
 345
 346     return 0;
 347
 348  error:
 349     DecoderError( p_fifo );
 350     if( p_dec )
 351     {
 352         if( p_dec->p_fifo )
 353             p_dec->p_fifo->b_error = 1;
 354
 355         /* End of the libmpeg2 decoder thread */
 356         CloseDecoder( p_dec );
 357     }
 358
 359     return -1;
 360 }
 361
 362 /*****************************************************************************
 363  * CloseDecoder: libmpeg2 decoder destruction
 364  *****************************************************************************/
 365 static void CloseDecoder( dec_thread_t * p_dec )
 366 {
 367     if( p_dec )
 368     {
 369         int i_pic;
 370
 371         if( p_dec->p_pes )
 372             input_DeletePES( p_dec->p_fifo->p_packets_mgt, p_dec->p_pes );
 373
 374         if( p_dec->p_vout )
 375         {
 376             /* Temporary hack to free the pictures in use by libmpeg2 */
 377             for( i_pic = 0; i_pic < p_dec->p_vout->render.i_pictures; i_pic++ )
 378             {
 379                 if( p_dec->p_vout->render.pp_picture[i_pic]->i_status ==
 380                       RESERVED_PICTURE )
 381                     vout_DestroyPicture( p_dec->p_vout,
 382                                      p_dec->p_vout->render.pp_picture[i_pic] );
 383             }
 384
 385             vout_Request( p_dec->p_fifo, p_dec->p_vout, 0, 0, 0, 0 );
 386         }
 387
 388         if( p_dec->p_synchro )
 389             vout_SynchroRelease( p_dec->p_synchro );
 390
 391         if( p_dec->p_mpeg2dec ) mpeg2_close( p_dec->p_mpeg2dec );
 392
 393         free( p_dec );
 394     }
 395 }
 396
 397 /*****************************************************************************
 398  * GetNewPicture: Get a new picture from the vout and set the buf struct
 399  *****************************************************************************/
 400 static picture_t *GetNewPicture( dec_thread_t *p_dec, uint8_t **pp_buf )
 401 {
 402     picture_t *p_pic;
 403
 404     /* Get a new picture */
 405     while( !(p_pic = vout_CreatePicture( p_dec->p_vout, 0, 0, 0 ) ) )
 406     {
 407         if( p_dec->p_fifo->b_die || p_dec->p_fifo->b_error )
 408             break;
 409
 410         msleep( VOUT_OUTMEM_SLEEP );
 411     }
 412     if( p_pic == NULL )
 413         return NULL;
 414     vout_LinkPicture( p_dec->p_vout, p_pic );
 415
 416     pp_buf[0] = p_pic->p[0].p_pixels;
 417     pp_buf[1] = p_pic->p[1].p_pixels;
 418     pp_buf[2] = p_pic->p[2].p_pixels;
 419
 420     return p_pic;
 421 }