modules/codec/spudec/spudec.c

   1 /*****************************************************************************
   2  * spudec.c : SPU decoder thread
   3  *****************************************************************************
   4  * Copyright (C) 2000-2001, 2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Sam Hocevar <sam@zoy.org>
   8  *          Laurent Aimar <fenrir@via.ecp.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24
  25 /*****************************************************************************
  26  * Preamble
  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_codec.h>
  35
  36 #include "spudec.h"
  37
  38 /*****************************************************************************
  39  * Module descriptor.
  40  *****************************************************************************/
  41 static int  DecoderOpen   ( vlc_object_t * );
  42 static int  PacketizerOpen( vlc_object_t * );
  43 static void Close         ( vlc_object_t * );
  44
  45 #define DVDSUBTRANS_DISABLE_TEXT N_("Disable DVD subtitle transparency")
  46 #define DVDSUBTRANS_DISABLE_LONGTEXT N_("Removes all transparency effects " \
  47                                         "used in DVD subtitles.")
  48
  49 vlc_module_begin ()
  50     set_description( N_("DVD subtitles decoder") )
  51     set_shortname( N_("DVD subtitles") )
  52     set_capability( "decoder", 75 )
  53     set_category( CAT_INPUT )
  54     set_subcategory( SUBCAT_INPUT_SCODEC )
  55     set_callbacks( DecoderOpen, Close )
  56
  57     add_bool( "dvdsub-transparency", false, NULL,
  58               DVDSUBTRANS_DISABLE_TEXT, DVDSUBTRANS_DISABLE_LONGTEXT, true )
  59     add_submodule ()
  60     set_description( N_("DVD subtitles packetizer") )
  61     set_capability( "packetizer", 50 )
  62     set_callbacks( PacketizerOpen, Close )
  63 vlc_module_end ()
  64
  65 /*****************************************************************************
  66  * Local prototypes
  67  *****************************************************************************/
  68 static block_t *      Reassemble( decoder_t *, block_t ** );
  69 static subpicture_t * Decode    ( decoder_t *, block_t ** );
  70 static block_t *      Packetize ( decoder_t *, block_t ** );
  71
  72 /*****************************************************************************
  73  * DecoderOpen
  74  *****************************************************************************
  75  * Tries to launch a decoder and return score so that the interface is able
  76  * to chose.
  77  *****************************************************************************/
  78 static int DecoderOpen( vlc_object_t *p_this )
  79 {
  80     decoder_t     *p_dec = (decoder_t*)p_this;
  81     decoder_sys_t *p_sys;
  82
  83     if( p_dec->fmt_in.i_codec != VLC_CODEC_SPU )
  84         return VLC_EGENERIC;
  85
  86     p_dec->p_sys = p_sys = malloc( sizeof( decoder_sys_t ) );
  87
  88     p_sys->b_packetizer = false;
  89     p_sys->b_disabletrans = var_InheritBool( p_dec, "dvdsub-transparency" );
  90     p_sys->i_spu_size = 0;
  91     p_sys->i_spu      = 0;
  92     p_sys->p_block    = NULL;
  93
  94     es_format_Init( &p_dec->fmt_out, SPU_ES, VLC_CODEC_SPU );
  95
  96     p_dec->pf_decode_sub = Decode;
  97     p_dec->pf_packetize  = NULL;
  98
  99     return VLC_SUCCESS;
 100 }
 101
 102 /*****************************************************************************
 103  * PacketizerOpen
 104  *****************************************************************************
 105  * Tries to launch a decoder and return score so that the interface is able
 106  * to chose.
 107  *****************************************************************************/
 108 static int PacketizerOpen( vlc_object_t *p_this )
 109 {
 110     decoder_t *p_dec = (decoder_t*)p_this;
 111
 112     if( DecoderOpen( p_this ) )
 113     {
 114         return VLC_EGENERIC;
 115     }
 116     p_dec->pf_packetize  = Packetize;
 117     p_dec->p_sys->b_packetizer = true;
 118     es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
 119     p_dec->fmt_out.i_codec = VLC_CODEC_SPU;
 120
 121     return VLC_SUCCESS;
 122 }
 123
 124 /*****************************************************************************
 125  * Close:
 126  *****************************************************************************/
 127 static void Close( vlc_object_t *p_this )
 128 {
 129     decoder_t     *p_dec = (decoder_t*)p_this;
 130     decoder_sys_t *p_sys = p_dec->p_sys;
 131
 132     if( p_sys->p_block )
 133     {
 134         block_ChainRelease( p_sys->p_block );
 135     }
 136
 137     free( p_sys );
 138 }
 139
 140 /*****************************************************************************
 141  * Decode:
 142  *****************************************************************************/
 143 static subpicture_t *Decode( decoder_t *p_dec, block_t **pp_block )
 144 {
 145     decoder_sys_t *p_sys = p_dec->p_sys;
 146     block_t       *p_spu_block;
 147     subpicture_t  *p_spu;
 148
 149     p_spu_block = Reassemble( p_dec, pp_block );
 150
 151     if( ! p_spu_block )
 152     {
 153         return NULL;
 154     }
 155
 156     /* FIXME: what the, we shouldn’t need to allocate 64k of buffer --sam. */
 157     p_sys->i_spu = block_ChainExtract( p_spu_block, p_sys->buffer, 65536 );
 158     p_sys->i_pts = p_spu_block->i_pts;
 159     block_ChainRelease( p_spu_block );
 160
 161     /* Parse and decode */
 162     p_spu = ParsePacket( p_dec );
 163
 164     /* reinit context */
 165     p_sys->i_spu_size = 0;
 166     p_sys->i_rle_size = 0;
 167     p_sys->i_spu      = 0;
 168     p_sys->p_block    = NULL;
 169
 170     return p_spu;
 171 }
 172
 173 /*****************************************************************************
 174  * Packetize:
 175  *****************************************************************************/
 176 static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
 177 {
 178     decoder_sys_t *p_sys = p_dec->p_sys;
 179     block_t       *p_spu = Reassemble( p_dec, pp_block );
 180
 181     if( ! p_spu )
 182     {
 183         return NULL;
 184     }
 185
 186     p_spu->i_dts = p_spu->i_pts;
 187     p_spu->i_length = 0;
 188
 189     /* reinit context */
 190     p_sys->i_spu_size = 0;
 191     p_sys->i_rle_size = 0;
 192     p_sys->i_spu      = 0;
 193     p_sys->p_block    = NULL;
 194
 195     return block_ChainGather( p_spu );
 196 }
 197
 198 /*****************************************************************************
 199  * Reassemble:
 200  *****************************************************************************/
 201 static block_t *Reassemble( decoder_t *p_dec, block_t **pp_block )
 202 {
 203     decoder_sys_t *p_sys = p_dec->p_sys;
 204     block_t *p_block;
 205
 206     if( pp_block == NULL || *pp_block == NULL ) return NULL;
 207     p_block = *pp_block;
 208     *pp_block = NULL;
 209
 210     if( p_sys->i_spu_size <= 0 &&
 211         ( p_block->i_pts <= VLC_TS_INVALID || p_block->i_buffer < 4 ) )
 212     {
 213         msg_Dbg( p_dec, "invalid starting packet (size < 4 or pts <=0)" );
 214         msg_Dbg( p_dec, "spu size: %d, i_pts: %"PRId64" i_buffer: %zu",
 215                  p_sys->i_spu_size, p_block->i_pts, p_block->i_buffer );
 216         block_Release( p_block );
 217         return NULL;
 218     }
 219
 220     block_ChainAppend( &p_sys->p_block, p_block );
 221     p_sys->i_spu += p_block->i_buffer;
 222
 223     if( p_sys->i_spu_size <= 0 )
 224     {
 225         p_sys->i_spu_size = ( p_block->p_buffer[0] << 8 )|
 226             p_block->p_buffer[1];
 227         p_sys->i_rle_size = ( ( p_block->p_buffer[2] << 8 )|
 228             p_block->p_buffer[3] ) - 4;
 229
 230         /* msg_Dbg( p_dec, "i_spu_size=%d i_rle=%d",
 231                     p_sys->i_spu_size, p_sys->i_rle_size ); */
 232
 233         if( p_sys->i_spu_size <= 0 || p_sys->i_rle_size >= p_sys->i_spu_size )
 234         {
 235             p_sys->i_spu_size = 0;
 236             p_sys->i_rle_size = 0;
 237             p_sys->i_spu      = 0;
 238             p_sys->p_block    = NULL;
 239
 240             block_Release( p_block );
 241             return NULL;
 242         }
 243     }
 244
 245     if( p_sys->i_spu >= p_sys->i_spu_size )
 246     {
 247         /* We have a complete sub */
 248         if( p_sys->i_spu > p_sys->i_spu_size )
 249             msg_Dbg( p_dec, "SPU packets size=%d should be %d",
 250                      p_sys->i_spu, p_sys->i_spu_size );
 251
 252         return p_sys->p_block;
 253     }
 254     return NULL;
 255 }