research.m1stereo.tv/gitweb/ - melted/blob - src/framework/mlt_factory.c

   1 /*
   2  * mlt_factory.c -- the factory method interfaces
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "config.h"
  22 #include "mlt.h"
  23 #include "mlt_repository.h"
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /** Singleton repositories
  30 */
  31
  32 static char *mlt_prefix = NULL;
  33 static mlt_properties global_properties = NULL;
  34 static mlt_properties object_list = NULL;
  35 static mlt_repository producers = NULL;
  36 static mlt_repository filters = NULL;
  37 static mlt_repository transitions = NULL;
  38 static mlt_repository consumers = NULL;
  39 static mlt_properties event_object = NULL;
  40 static int unique_id = 0;
  41
  42 /** Event transmitters.
  43 */
  44
  45 static void mlt_factory_create_request( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
  46 {
  47         if ( listener != NULL )
  48                 listener( owner, this, ( char * )args[ 0 ], ( char * )args[ 1 ], ( mlt_service * )args[ 2 ] );
  49 }
  50
  51 static void mlt_factory_create_done( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
  52 {
  53         if ( listener != NULL )
  54                 listener( owner, this, ( char * )args[ 0 ], ( char * )args[ 1 ], ( mlt_service )args[ 2 ] );
  55 }
  56
  57 /** Construct the factories.
  58 */
  59
  60 int mlt_factory_init( const char *prefix )
  61 {
  62         // Only initialise once
  63         if ( mlt_prefix == NULL )
  64         {
  65                 // Allow user over rides
  66                 if ( prefix == NULL || !strcmp( prefix, "" ) )
  67                         prefix = getenv( "MLT_REPOSITORY" );
  68
  69                 // If no directory is specified, default to install directory
  70                 if ( prefix == NULL )
  71                         prefix = PREFIX_DATA;
  72
  73                 // Store the prefix for later retrieval
  74                 mlt_prefix = strdup( prefix );
  75
  76                 // Initialise the pool
  77                 mlt_pool_init( );
  78
  79                 // Create and set up the events object
  80                 event_object = mlt_properties_new( );
  81                 mlt_events_init( event_object );
  82                 mlt_events_register( event_object, "producer-create-request", ( mlt_transmitter )mlt_factory_create_request );
  83                 mlt_events_register( event_object, "producer-create-done", ( mlt_transmitter )mlt_factory_create_done );
  84                 mlt_events_register( event_object, "filter-create-request", ( mlt_transmitter )mlt_factory_create_request );
  85                 mlt_events_register( event_object, "filter-create-done", ( mlt_transmitter )mlt_factory_create_done );
  86                 mlt_events_register( event_object, "transition-create-request", ( mlt_transmitter )mlt_factory_create_request );
  87                 mlt_events_register( event_object, "transition-create-done", ( mlt_transmitter )mlt_factory_create_done );
  88                 mlt_events_register( event_object, "consumer-create-request", ( mlt_transmitter )mlt_factory_create_request );
  89                 mlt_events_register( event_object, "consumer-create-done", ( mlt_transmitter )mlt_factory_create_done );
  90
  91                 // Create the global properties
  92                 global_properties = mlt_properties_new( );
  93
  94                 // Create the object list.
  95                 object_list = mlt_properties_new( );
  96
  97                 // Create a repository for each service type
  98                 producers = mlt_repository_init( object_list, prefix, "producers", "mlt_create_producer" );
  99                 filters = mlt_repository_init( object_list, prefix, "filters", "mlt_create_filter" );
 100                 transitions = mlt_repository_init( object_list, prefix, "transitions", "mlt_create_transition" );
 101                 consumers = mlt_repository_init( object_list, prefix, "consumers", "mlt_create_consumer" );
 102
 103                 // Force a clean up when app closes
 104                 atexit( mlt_factory_close );
 105         }
 106
 107         // Allow property refresh on a subsequent initialisation
 108         if ( global_properties != NULL )
 109         {
 110                 mlt_properties_set_or_default( global_properties, "MLT_NORMALISATION", getenv( "MLT_NORMALISATION" ), "PAL" );
 111                 mlt_properties_set_or_default( global_properties, "MLT_PRODUCER", getenv( "MLT_PRODUCER" ), "fezzik" );
 112                 mlt_properties_set_or_default( global_properties, "MLT_CONSUMER", getenv( "MLT_CONSUMER" ), "sdl" );
 113                 mlt_properties_set( global_properties, "MLT_TEST_CARD", getenv( "MLT_TEST_CARD" ) );
 114                 mlt_properties_set_or_default( global_properties, "MLT_PROFILE", getenv( "MLT_PROFILE" ), "dv_pal" );
 115
 116                 // Load the most appropriate profile
 117                 // MLT_PROFILE preferred
 118                 if ( getenv( "MLT_PROFILE" ) )
 119                 {
 120                         if ( !mlt_profile_select( mlt_environment( "MLT_PROFILE" ) ) )
 121                                 mlt_profile_load_file( mlt_environment( "MLT_PROFILE" ) );
 122                 }
 123                 // MLT_NORMALISATION backwards compatibility
 124                 else if ( strcmp( mlt_environment( "MLT_NORMALISATION" ), "PAL" ) )
 125                         mlt_profile_select( "dv_ntsc" );
 126                 else
 127                         mlt_profile_select( "dv_pal" );
 128
 129                 // destroy an invalid profile so it can be constructed from hard defauls
 130                 if ( mlt_profile_get()->width == 0 )
 131                         mlt_profile_close();
 132
 133                 // Set MLT_NORMALISATION to appease legacy modules
 134                 if ( !getenv( "MLT_NORMALISATION" ) )
 135                 {
 136                         const char *profile = mlt_profile_get()->name;
 137                         if ( strstr( profile, "_ntsc" ) || strstr( profile, "_atsc" ) )
 138                                 setenv( "MLT_NORMALISATION", "NTSC", 1 );
 139                         else if ( strstr( profile, "_pal" ) )
 140                                 setenv( "MLT_NORMALISATION", "PAL", 1 );
 141                 }
 142         }
 143
 144
 145         return 0;
 146 }
 147
 148 /** Fetch the events object.
 149 */
 150
 151 mlt_properties mlt_factory_event_object( )
 152 {
 153         return event_object;
 154 }
 155
 156 /** Fetch the prefix used in this instance.
 157 */
 158
 159 const char *mlt_factory_prefix( )
 160 {
 161         return mlt_prefix;
 162 }
 163
 164 /** Get a value from the environment.
 165 */
 166
 167 char *mlt_environment( const char *name )
 168 {
 169         return mlt_properties_get( global_properties, name );
 170 }
 171
 172 /** Fetch a producer from the repository.
 173 */
 174
 175 mlt_producer mlt_factory_producer( const char *service, void *input )
 176 {
 177         mlt_producer obj = NULL;
 178
 179         // Pick up the default normalising producer if necessary
 180         if ( service == NULL )
 181                 service = mlt_environment( "MLT_PRODUCER" );
 182
 183         // Offer the application the chance to 'create'
 184         mlt_events_fire( event_object, "producer-create-request", service, input, &obj, NULL );
 185
 186         // Try to instantiate via the specified service
 187         if ( obj == NULL )
 188         {
 189                 obj = mlt_repository_fetch( producers, service, input );
 190                 mlt_events_fire( event_object, "producer-create-done", service, input, obj, NULL );
 191                 if ( obj != NULL )
 192                 {
 193                         mlt_properties properties = MLT_PRODUCER_PROPERTIES( obj );
 194                         mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 195                         mlt_properties_set( properties, "mlt_type", "producer" );
 196                         if ( mlt_properties_get_int( properties, "_mlt_service_hidden" ) == 0 )
 197                                 mlt_properties_set( properties, "mlt_service", service );
 198                 }
 199         }
 200         return obj;
 201 }
 202
 203 /** Fetch a filter from the repository.
 204 */
 205
 206 mlt_filter mlt_factory_filter( const char *service, void *input )
 207 {
 208         mlt_filter obj = NULL;
 209
 210         // Offer the application the chance to 'create'
 211         mlt_events_fire( event_object, "filter-create-request", service, input, &obj, NULL );
 212
 213         if ( obj == NULL )
 214         {
 215                 obj = mlt_repository_fetch( filters, service, input );
 216                 mlt_events_fire( event_object, "filter-create-done", service, input, obj, NULL );
 217         }
 218
 219         if ( obj != NULL )
 220         {
 221                 mlt_properties properties = MLT_FILTER_PROPERTIES( obj );
 222                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 223                 mlt_properties_set( properties, "mlt_type", "filter" );
 224                 mlt_properties_set( properties, "mlt_service", service );
 225         }
 226         return obj;
 227 }
 228
 229 /** Fetch a transition from the repository.
 230 */
 231
 232 mlt_transition mlt_factory_transition( const char *service, void *input )
 233 {
 234         mlt_transition obj = NULL;
 235
 236         // Offer the application the chance to 'create'
 237         mlt_events_fire( event_object, "transition-create-request", service, input, &obj, NULL );
 238
 239         if ( obj == NULL )
 240         {
 241                 obj = mlt_repository_fetch( transitions, service, input );
 242                 mlt_events_fire( event_object, "transition-create-done", service, input, obj, NULL );
 243         }
 244
 245         if ( obj != NULL )
 246         {
 247                 mlt_properties properties = MLT_TRANSITION_PROPERTIES( obj );
 248                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 249                 mlt_properties_set( properties, "mlt_type", "transition" );
 250                 mlt_properties_set( properties, "mlt_service", service );
 251         }
 252         return obj;
 253 }
 254
 255 /** Fetch a consumer from the repository
 256 */
 257
 258 mlt_consumer mlt_factory_consumer( const char *service, void *input )
 259 {
 260         mlt_consumer obj = NULL;
 261
 262         if ( service == NULL )
 263                 service = mlt_environment( "MLT_CONSUMER" );
 264
 265         // Offer the application the chance to 'create'
 266         mlt_events_fire( event_object, "consumer-create-request", service, input, &obj, NULL );
 267
 268         if ( obj == NULL )
 269         {
 270                 obj = mlt_repository_fetch( consumers, service, input );
 271                 mlt_events_fire( event_object, "consumer-create-done", service, input, obj, NULL );
 272         }
 273
 274         if ( obj != NULL )
 275         {
 276                 mlt_properties properties = MLT_CONSUMER_PROPERTIES( obj );
 277                 mlt_properties_set_int( properties, "_unique_id", ++ unique_id );
 278                 mlt_properties_set( properties, "mlt_type", "consumer" );
 279                 mlt_properties_set( properties, "mlt_service", service );
 280         }
 281         return obj;
 282 }
 283
 284 /** Register an object for clean up.
 285 */
 286
 287 void mlt_factory_register_for_clean_up( void *ptr, mlt_destructor destructor )
 288 {
 289         char unique[ 256 ];
 290         sprintf( unique, "%08d", mlt_properties_count( global_properties ) );
 291         mlt_properties_set_data( global_properties, unique, ptr, 0, destructor, NULL );
 292 }
 293
 294 /** Close the factory.
 295 */
 296
 297 void mlt_factory_close( )
 298 {
 299         if ( mlt_prefix != NULL )
 300         {
 301                 mlt_properties_close( event_object );
 302                 mlt_repository_close( producers );
 303                 mlt_repository_close( filters );
 304                 mlt_repository_close( transitions );
 305                 mlt_repository_close( consumers );
 306                 mlt_properties_close( global_properties );
 307                 mlt_properties_close( object_list );
 308                 free( mlt_prefix );
 309                 mlt_prefix = NULL;
 310                 mlt_pool_close( );
 311                 mlt_profile_close();
 312         }
 313 }