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

   1 /*****************************************************************************\r
   2  * libmpeg2.c: mpeg2 video decoder module making use of libmpeg2.\r
   3  *****************************************************************************\r
   4  * Copyright (C) 1999-2001 VideoLAN\r
   5  * $Id: libmpeg2.c,v 1.5 2003/03/26 22:56:39 gbazin Exp $\r
   6  *\r
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>\r
   8  *\r
   9  * This program is free software; you can redistribute it and/or modify\r
  10  * it under the terms of the GNU General Public License as published by\r
  11  * the Free Software Foundation; either version 2 of the License, or\r
  12  * (at your option) any later version.\r
  13  * \r
  14  * This program is distributed in the hope that it will be useful,\r
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of\r
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
  17  * GNU General Public License for more details.\r
  18  *\r
  19  * You should have received a copy of the GNU General Public License\r
  20  * along with this program; if not, write to the Free Software\r
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.\r
  22  *****************************************************************************/\r
  23 \r
  24 /*****************************************************************************\r
  25  * Preamble\r
  26  *****************************************************************************/\r
  27 #include <vlc/vlc.h>\r
  28 #include <vlc/vout.h>\r
  29 #include <vlc/input.h>\r
  30 #include <vlc/decoder.h>\r
  31 \r
  32 #include <stdlib.h>                                      /* malloc(), free() */\r
  33 #include <string.h>                                    /* memcpy(), memset() */\r
  34 \r
  35 #include <mpeg2dec/mpeg2.h>\r
  36 \r
  37 /* Aspect ratio (ISO/IEC 13818-2 section 6.3.3, table 6-3) */\r
  38 #define AR_SQUARE_PICTURE       1                           /* square pixels */\r
  39 #define AR_3_4_PICTURE          2                        /* 3:4 picture (TV) */\r
  40 #define AR_16_9_PICTURE         3              /* 16:9 picture (wide screen) */\r
  41 #define AR_221_1_PICTURE        4                  /* 2.21:1 picture (movie) */\r
  42 \r
  43 /*****************************************************************************\r
  44  * dec_thread_t : libmpeg2 decoder thread descriptor\r
  45  *****************************************************************************/\r
  46 typedef struct dec_thread_t\r
  47 {\r
  48     /*\r
  49      * libmpeg2 properties\r
  50      */\r
  51     mpeg2dec_t          *p_mpeg2dec;\r
  52     const mpeg2_info_t  *p_info;\r
  53 \r
  54     /*\r
  55      * Input properties\r
  56      */\r
  57     decoder_fifo_t   *p_fifo;                  /* stores the PES stream data */\r
  58     pes_packet_t     *p_pes;                  /* current PES we are decoding */\r
  59     mtime_t          i_pts;\r
  60     mtime_t          i_previous_pts;\r
  61     mtime_t          i_current_pts;\r
  62     mtime_t          i_period_remainder;\r
  63 \r
  64     /*\r
  65      * Output properties\r
  66      */\r
  67     vout_thread_t *p_vout;\r
  68 \r
  69 } dec_thread_t;\r
  70 \r
  71 /*****************************************************************************\r
  72  * Local prototypes\r
  73  *****************************************************************************/\r
  74 static int  OpenDecoder  ( vlc_object_t * );\r
  75 static int  RunDecoder   ( decoder_fifo_t * );\r
  76 static void CloseDecoder ( dec_thread_t * );\r
  77 \r
  78 /*****************************************************************************\r
  79  * Module descriptor\r
  80  *****************************************************************************/\r
  81 vlc_module_begin();\r
  82     set_description( _("libmpeg2 decoder module") );\r
  83     set_capability( "decoder", 40 );\r
  84     set_callbacks( OpenDecoder, NULL );\r
  85     add_shortcut( "libmpeg2" );\r
  86 vlc_module_end();\r
  87 \r
  88 /*****************************************************************************\r
  89  * OpenDecoder: probe the decoder and return score\r
  90  *****************************************************************************/\r
  91 static int OpenDecoder( vlc_object_t *p_this )\r
  92 {\r
  93     decoder_fifo_t *p_fifo = (decoder_fifo_t*) p_this;\r
  94 \r
  95     if( p_fifo->i_fourcc != VLC_FOURCC('m','p','g','v') )\r
  96     {\r
  97         return VLC_EGENERIC;\r
  98     }\r
  99 \r
 100     p_fifo->pf_run = RunDecoder;\r
 101     return VLC_SUCCESS;\r
 102 }\r
 103 /*****************************************************************************\r
 104  * RunDecoder: the libmpeg2 decoder\r
 105  *****************************************************************************/\r
 106 static int RunDecoder( decoder_fifo_t *p_fifo )\r
 107 {\r
 108     dec_thread_t    *p_dec;\r
 109     data_packet_t   *p_data = NULL;\r
 110     mpeg2_state_t   state;\r
 111     picture_t       *p_pic;\r
 112     int             i_aspect, i_chroma;\r
 113 \r
 114     /* Allocate the memory needed to store the thread's structure */\r
 115     if( (p_dec = (dec_thread_t *)malloc (sizeof(dec_thread_t)) )\r
 116         == NULL)\r
 117     {\r
 118         msg_Err( p_fifo, "out of memory" );\r
 119         goto error;\r
 120     }\r
 121 \r
 122     /* Initialize the thread properties */\r
 123     memset( p_dec, 0, sizeof(dec_thread_t) );\r
 124     p_dec->p_fifo     = p_fifo;\r
 125     p_dec->p_pes      = NULL;\r
 126     p_dec->p_vout     = NULL;\r
 127     p_dec->p_mpeg2dec = NULL;\r
 128     p_dec->p_info     = NULL;\r
 129     p_dec->i_pts      = mdate() + DEFAULT_PTS_DELAY;\r
 130     p_dec->i_current_pts  = 0;\r
 131     p_dec->i_previous_pts = 0;\r
 132     p_dec->i_period_remainder = 0;\r
 133 \r
 134     /* Initialize decoder */\r
 135     p_dec->p_mpeg2dec = mpeg2_init();\r
 136     if( p_dec->p_mpeg2dec == NULL)\r
 137         goto error;\r
 138 \r
 139     p_dec->p_info = mpeg2_info( p_dec->p_mpeg2dec );\r
 140 \r
 141     /* libmpeg2 decoder thread's main loop */\r
 142     while( (!p_dec->p_fifo->b_die) && (!p_dec->p_fifo->b_error) )\r
 143     {\r
 144         state = mpeg2_parse( p_dec->p_mpeg2dec );\r
 145 \r
 146         switch( state )\r
 147         {\r
 148         case STATE_BUFFER:\r
 149             /* Feed libmpeg2 a data packet at a time */\r
 150             if( p_data == NULL )\r
 151             {\r
 152                 /* Get the next PES */\r
 153                 if( p_dec->p_pes )\r
 154                     input_DeletePES( p_dec->p_fifo->p_packets_mgt,\r
 155                                      p_dec->p_pes );\r
 156 \r
 157                 input_ExtractPES( p_dec->p_fifo, &p_dec->p_pes );\r
 158                 if( !p_dec->p_pes )\r
 159                 {\r
 160                     p_dec->p_fifo->b_error = 1;\r
 161                     break;\r
 162                 }\r
 163 \r
 164                 if( p_dec->p_pes->i_pts )\r
 165                 {\r
 166                     mpeg2_pts( p_dec->p_mpeg2dec,\r
 167                                (uint32_t)p_dec->p_pes->i_pts );\r
 168                     p_dec->i_previous_pts = p_dec->i_current_pts;\r
 169                     p_dec->i_current_pts = p_dec->p_pes->i_pts;\r
 170                 }\r
 171                 p_data = p_dec->p_pes->p_first;\r
 172             }\r
 173 \r
 174             if( p_data != NULL )\r
 175             {\r
 176                 mpeg2_buffer( p_dec->p_mpeg2dec,\r
 177                               p_data->p_payload_start,\r
 178                               p_data->p_payload_end );\r
 179 \r
 180                 p_data = p_data->p_next;\r
 181             }\r
 182             break;\r
 183 \r
 184         case STATE_SEQUENCE:\r
 185             /* Initialize video output */\r
 186 \r
 187             /* Check whether the input gives a particular aspect ratio */\r
 188             if( p_dec->p_fifo->p_demux_data\r
 189                 && ( *(int*)(p_dec->p_fifo->p_demux_data) & 0x7 ) )\r
 190             {\r
 191                 i_aspect = *(int*)(p_dec->p_fifo->p_demux_data);\r
 192                 switch( i_aspect )\r
 193                 {\r
 194                 case AR_3_4_PICTURE:\r
 195                     i_aspect = VOUT_ASPECT_FACTOR * 4 / 3;\r
 196                     break;\r
 197                 case AR_16_9_PICTURE:\r
 198                     i_aspect = VOUT_ASPECT_FACTOR * 16 / 9;\r
 199                     break;\r
 200                 case AR_221_1_PICTURE:\r
 201                     i_aspect = VOUT_ASPECT_FACTOR * 221 / 100;\r
 202                     break;\r
 203                 case AR_SQUARE_PICTURE:\r
 204                 default:\r
 205                     i_aspect = VOUT_ASPECT_FACTOR *\r
 206                                    p_dec->p_info->sequence->width /\r
 207                                    p_dec->p_info->sequence->height;\r
 208                     break;\r
 209                 }\r
 210             }\r
 211             else\r
 212             {\r
 213                 /* Use the value provided in the MPEG sequence header */\r
 214                 i_aspect = ((uint64_t)p_dec->p_info->sequence->width) *\r
 215                     p_dec->p_info->sequence->pixel_width * VOUT_ASPECT_FACTOR /\r
 216                     p_dec->p_info->sequence->height /\r
 217                     p_dec->p_info->sequence->pixel_height;\r
 218             }\r
 219 \r
 220             i_chroma = VLC_FOURCC('Y','V','1','2');\r
 221 \r
 222             p_dec->p_vout = vout_Request( p_dec->p_fifo, p_dec->p_vout,\r
 223                                           p_dec->p_info->sequence->width,\r
 224                                           p_dec->p_info->sequence->height,\r
 225                                           i_chroma, i_aspect );\r
 226             break;\r
 227 \r
 228         case STATE_PICTURE:\r
 229         {\r
 230             uint8_t *buf[3];\r
 231 \r
 232             /* Get a new picture */\r
 233             while( !(p_pic = vout_CreatePicture( p_dec->p_vout, 0, 0, 0 ) ) )\r
 234             {\r
 235                 if( p_dec->p_fifo->b_die || p_dec->p_fifo->b_error )\r
 236                     break;\r
 237 \r
 238                 msleep( VOUT_OUTMEM_SLEEP );\r
 239             }\r
 240             if( p_pic == NULL )\r
 241                 break;\r
 242 \r
 243             buf[0] = p_pic->p[0].p_pixels;\r
 244             buf[1] = p_pic->p[1].p_pixels;\r
 245             buf[2] = p_pic->p[2].p_pixels;\r
 246             mpeg2_set_buf( p_dec->p_mpeg2dec, buf, p_pic );\r
 247 \r
 248             /* Store the date for the picture */\r
 249             if( p_dec->p_info->current_picture->flags & PIC_FLAG_PTS )\r
 250             {\r
 251                 p_pic->date = ( p_dec->p_info->current_picture->pts ==\r
 252                                 (uint32_t)p_dec->i_current_pts ) ?\r
 253                               p_dec->i_current_pts : p_dec->i_previous_pts;\r
 254             }\r
 255         }\r
 256         break;\r
 257 \r
 258         case STATE_END:\r
 259         case STATE_SLICE:\r
 260             if( p_dec->p_info->display_fbuf\r
 261                 && p_dec->p_info->display_fbuf->id )\r
 262             {\r
 263                 p_pic = (picture_t *)p_dec->p_info->display_fbuf->id;\r
 264 \r
 265                 /* Date the new picture */\r
 266                 if( p_dec->p_info->display_picture->flags & PIC_FLAG_PTS )\r
 267                 {\r
 268                     p_dec->i_pts = p_pic->date;\r
 269                     p_dec->i_period_remainder = 0;\r
 270                 }\r
 271                 else\r
 272                 {\r
 273                     p_dec->i_pts += ( (p_dec->p_info->sequence->frame_period +\r
 274                                        p_dec->i_period_remainder) / 27 );\r
 275                     p_dec->i_period_remainder =\r
 276                         p_dec->p_info->sequence->frame_period +\r
 277                         p_dec->i_period_remainder -\r
 278                         ( p_dec->p_info->sequence->frame_period +\r
 279                           p_dec->i_period_remainder ) / 27 * 27;\r
 280                 }\r
 281                 vout_DatePicture( p_dec->p_vout, p_pic, p_dec->i_pts );\r
 282 \r
 283                 vout_DisplayPicture( p_dec->p_vout, p_pic );\r
 284 \r
 285                 /* Handle pulldown by adding some delay to the pts of the next\r
 286                  * picture. */\r
 287                 if( p_dec->p_info->display_picture->nb_fields > 2 )\r
 288                 {\r
 289                     int i_repeat_fields =\r
 290                         p_dec->p_info->display_picture->nb_fields - 2;\r
 291 \r
 292                     p_dec->i_pts += ( (p_dec->p_info->sequence->frame_period +\r
 293                                        p_dec->i_period_remainder)\r
 294                                       / 27 / 2 * i_repeat_fields );\r
 295                     p_dec->i_period_remainder =\r
 296                         p_dec->p_info->sequence->frame_period +\r
 297                         p_dec->i_period_remainder -\r
 298                         ( p_dec->p_info->sequence->frame_period +\r
 299                           p_dec->i_period_remainder ) / 27 / 2 * 27 * 2;\r
 300                 }\r
 301             }\r
 302             break;\r
 303 \r
 304         default:\r
 305             break;\r
 306         }\r
 307     }\r
 308 \r
 309     /* If b_error is set, the libmpeg2 decoder thread enters the error loop */\r
 310     if( p_dec->p_fifo->b_error )\r
 311     {\r
 312         DecoderError( p_dec->p_fifo );\r
 313     }\r
 314 \r
 315     /* End of the libmpeg2 decoder thread */\r
 316     CloseDecoder( p_dec );\r
 317 \r
 318     return 0;\r
 319 \r
 320  error:\r
 321     DecoderError( p_fifo );\r
 322     if( p_dec )\r
 323     {\r
 324         if( p_dec->p_fifo )\r
 325             p_dec->p_fifo->b_error = 1;\r
 326 \r
 327         /* End of the libmpeg2 decoder thread */\r
 328         CloseDecoder( p_dec );\r
 329     }\r
 330 \r
 331     return -1;\r
 332 }\r
 333 \r
 334 /*****************************************************************************\r
 335  * CloseDecoder: libmpeg2 decoder destruction\r
 336  *****************************************************************************/\r
 337 static void CloseDecoder( dec_thread_t * p_dec )\r
 338 {\r
 339     if( p_dec )\r
 340     {\r
 341         if( p_dec->p_pes )\r
 342             input_DeletePES( p_dec->p_fifo->p_packets_mgt, p_dec->p_pes );\r
 343 \r
 344         vout_Request( p_dec->p_fifo, p_dec->p_vout, 0, 0, 0, 0 );\r
 345 \r
 346         if( p_dec->p_mpeg2dec ) mpeg2_close( p_dec->p_mpeg2dec );\r
 347 \r
 348         free( p_dec );\r
 349     }\r
 350 }\r