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

   1 /*
   2  * mlt_service.c -- interface for all service classes
   3  * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
   4  * Author: Charles Yates <charles.yates@pandora.be>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software Foundation,
  18  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 #include "config.h"
  22 #include "mlt_service.h"
  23 #include "mlt_filter.h"
  24 #include "mlt_frame.h"
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /** IMPORTANT NOTES
  30
  31         The base service implements a null frame producing service - as such,
  32         it is functional without extension and will produce test cards frames
  33         and PAL sized audio frames.
  34
  35         PLEASE DO NOT CHANGE THIS BEHAVIOUR!!! OVERRIDE THE METHODS THAT
  36         CONTROL THIS IN EXTENDING CLASSES.
  37 */
  38
  39 /** Private service definition.
  40 */
  41
  42 typedef struct
  43 {
  44         int size;
  45         int count;
  46         mlt_service *in;
  47         mlt_service out;
  48         int filter_count;
  49         int filter_size;
  50         mlt_filter *filters;
  51 }
  52 mlt_service_base;
  53
  54 /** Private methods
  55 */
  56
  57 static void mlt_service_disconnect( mlt_service this );
  58 static void mlt_service_connect( mlt_service this, mlt_service that );
  59 static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index );
  60 static void mlt_service_property_changed( mlt_listener, mlt_properties owner, mlt_service this, void **args );
  61
  62 /** Constructor
  63 */
  64
  65 int mlt_service_init( mlt_service this, void *child )
  66 {
  67         int error = 0;
  68
  69         // Initialise everything to NULL
  70         memset( this, 0, sizeof( struct mlt_service_s ) );
  71
  72         // Assign the child
  73         this->child = child;
  74
  75         // Generate local space
  76         this->local = calloc( sizeof( mlt_service_base ), 1 );
  77
  78         // Associate the methods
  79         this->get_frame = service_get_frame;
  80
  81         // Initialise the properties
  82         error = mlt_properties_init( &this->parent, this );
  83         if ( error == 0 )
  84         {
  85                 this->parent.close = ( mlt_destructor )mlt_service_close;
  86                 this->parent.close_object = this;
  87
  88                 mlt_events_init( &this->parent );
  89                 mlt_events_register( &this->parent, "service-changed", NULL );
  90                 mlt_events_register( &this->parent, "property-changed", ( mlt_transmitter )mlt_service_property_changed );
  91         }
  92
  93         return error;
  94 }
  95
  96 static void mlt_service_property_changed( mlt_listener listener, mlt_properties owner, mlt_service this, void **args )
  97 {
  98         if ( listener != NULL )
  99                 listener( owner, this, ( char * )args[ 0 ] );
 100 }
 101
 102 /** Connect a producer service.
 103         Returns: > 0 warning, == 0 success, < 0 serious error
 104                          1 = this service does not accept input
 105                          2 = the producer is invalid
 106                          3 = the producer is already registered with this consumer
 107 */
 108
 109 int mlt_service_connect_producer( mlt_service this, mlt_service producer, int index )
 110 {
 111         int i = 0;
 112
 113         // Get the service base
 114         mlt_service_base *base = this->local;
 115
 116         // Check if the producer is already registered with this service
 117         for ( i = 0; i < base->count; i ++ )
 118                 if ( base->in[ i ] == producer )
 119                         return 3;
 120
 121         // Allocate space
 122         if ( index >= base->size )
 123         {
 124                 int new_size = base->size + index + 10;
 125                 base->in = realloc( base->in, new_size * sizeof( mlt_service ) );
 126                 if ( base->in != NULL )
 127                 {
 128                         for ( i = base->size; i < new_size; i ++ )
 129                                 base->in[ i ] = NULL;
 130                         base->size = new_size;
 131                 }
 132         }
 133
 134         // If we have space, assign the input
 135         if ( base->in != NULL && index >= 0 && index < base->size )
 136         {
 137                 // Get the current service
 138                 mlt_service current = base->in[ index ];
 139
 140                 // Increment the reference count on this producer
 141                 if ( producer != NULL )
 142                         mlt_properties_inc_ref( mlt_service_properties( producer ) );
 143
 144                 // Now we disconnect the producer service from its consumer
 145                 mlt_service_disconnect( producer );
 146
 147                 // Add the service to index specified
 148                 base->in[ index ] = producer;
 149
 150                 // Determine the number of active tracks
 151                 if ( index >= base->count )
 152                         base->count = index + 1;
 153
 154                 // Now we connect the producer to its connected consumer
 155                 mlt_service_connect( producer, this );
 156
 157                 // Close the current service
 158                 mlt_service_close( current );
 159
 160                 // Inform caller that all went well
 161                 return 0;
 162         }
 163         else
 164         {
 165                 return -1;
 166         }
 167 }
 168
 169 /** Disconnect this service from its consumer.
 170 */
 171
 172 static void mlt_service_disconnect( mlt_service this )
 173 {
 174         if ( this != NULL )
 175         {
 176                 // Get the service base
 177                 mlt_service_base *base = this->local;
 178
 179                 // Disconnect
 180                 base->out = NULL;
 181         }
 182 }
 183
 184 /** Obtain the consumer this service is connected to.
 185 */
 186
 187 mlt_service mlt_service_consumer( mlt_service this )
 188 {
 189         // Get the service base
 190         mlt_service_base *base = this->local;
 191
 192         // Return the connected consumer
 193         return base->out;
 194 }
 195
 196 /** Obtain the producer this service is connected to.
 197 */
 198
 199 mlt_service mlt_service_producer( mlt_service this )
 200 {
 201         // Get the service base
 202         mlt_service_base *base = this->local;
 203
 204         // Return the connected producer
 205         return base->count > 0 ? base->in[ base->count - 1 ] : NULL;
 206 }
 207
 208 /** Associate this service to the consumer.
 209 */
 210
 211 static void mlt_service_connect( mlt_service this, mlt_service that )
 212 {
 213         if ( this != NULL )
 214         {
 215                 // Get the service base
 216                 mlt_service_base *base = this->local;
 217
 218                 // There's a bit more required here...
 219                 base->out = that;
 220         }
 221 }
 222
 223 /** Get the first connected producer service.
 224 */
 225
 226 mlt_service mlt_service_get_producer( mlt_service this )
 227 {
 228         mlt_service producer = NULL;
 229
 230         // Get the service base
 231         mlt_service_base *base = this->local;
 232
 233         if ( base->in != NULL )
 234                 producer = base->in[ 0 ];
 235
 236         return producer;
 237 }
 238
 239 /** Default implementation of get_frame.
 240 */
 241
 242 static int service_get_frame( mlt_service this, mlt_frame_ptr frame, int index )
 243 {
 244         mlt_service_base *base = this->local;
 245         if ( index < base->count )
 246         {
 247                 mlt_service producer = base->in[ index ];
 248                 if ( producer != NULL )
 249                         return mlt_service_get_frame( producer, frame, index );
 250         }
 251         *frame = mlt_frame_init( );
 252         return 0;
 253 }
 254
 255 /** Return the properties object.
 256 */
 257
 258 mlt_properties mlt_service_properties( mlt_service self )
 259 {
 260         return self != NULL ? &self->parent : NULL;
 261 }
 262
 263 /** Recursively apply attached filters
 264 */
 265
 266 void mlt_service_apply_filters( mlt_service this, mlt_frame frame, int index )
 267 {
 268         int i;
 269         mlt_properties frame_properties = mlt_frame_properties( frame );
 270         mlt_properties filter_properties = mlt_service_properties( this );
 271         mlt_service_base *base = this->local;
 272         mlt_position position = mlt_properties_get_position( frame_properties, "_position" );
 273
 274         // Hmm - special case for cuts - apply filters from the parent first
 275         if ( mlt_properties_get_int( filter_properties, "_cut" ) )
 276                 mlt_service_apply_filters( ( mlt_service )mlt_properties_get_data( filter_properties, "_cut_parent", NULL ), frame, 0 );
 277
 278         if ( index == 0 || mlt_properties_get_int( filter_properties, "_filter_private" ) == 0 )
 279         {
 280                 // Process the frame with the attached filters
 281                 for ( i = 0; i < base->filter_count; i ++ )
 282                 {
 283                         if ( base->filters[ i ] != NULL )
 284                         {
 285                                 mlt_properties properties = mlt_filter_properties( base->filters[ i ] );
 286                                 mlt_position in = mlt_properties_get_position( properties, "in" );
 287                                 mlt_position out = mlt_properties_get_position( properties, "out" );
 288                                 if ( ( in == 0 && out == 0 ) || ( position >= in && ( position <= out || out == 0 ) ) )
 289                                 {
 290                                         mlt_filter_process( base->filters[ i ], frame );
 291                                         mlt_properties_set_position( frame_properties, "_position", position - in );
 292                                         mlt_service_apply_filters( mlt_filter_service( base->filters[ i ] ), frame, index + 1 );
 293                                         mlt_properties_set_position( frame_properties, "_position", position );
 294                                 }
 295                         }
 296                 }
 297         }
 298 }
 299
 300 /** Obtain a frame.
 301 */
 302
 303 int mlt_service_get_frame( mlt_service this, mlt_frame_ptr frame, int index )
 304 {
 305         if ( this != NULL )
 306         {
 307                 int result = this->get_frame( this, frame, index );
 308                 if ( result == 0 )
 309                         mlt_service_apply_filters( this, *frame, 1 );
 310                 return result;
 311         }
 312         *frame = mlt_frame_init( );
 313         return 0;
 314 }
 315
 316 static void mlt_service_filter_changed( mlt_service owner, mlt_service this )
 317 {
 318         mlt_events_fire( mlt_service_properties( this ), "service-changed", NULL );
 319 }
 320
 321 /** Attach a filter.
 322 */
 323
 324 int mlt_service_attach( mlt_service this, mlt_filter filter )
 325 {
 326         int error = this == NULL || filter == NULL;
 327         if ( error == 0 )
 328         {
 329                 int i = 0;
 330                 mlt_properties properties = mlt_service_properties( this );
 331                 mlt_service_base *base = this->local;
 332
 333                 for ( i = 0; error == 0 && i < base->filter_count; i ++ )
 334                         if ( base->filters[ i ] == filter )
 335                                 error = 1;
 336
 337                 if ( error == 0 )
 338                 {
 339                         if ( base->filter_count == base->filter_size )
 340                         {
 341                                 base->filter_size += 10;
 342                                 base->filters = realloc( base->filters, base->filter_size * sizeof( mlt_filter ) );
 343                         }
 344
 345                         if ( base->filters != NULL )
 346                         {
 347                                 mlt_properties props = mlt_filter_properties( filter );
 348                                 mlt_properties_inc_ref( mlt_filter_properties( filter ) );
 349                                 base->filters[ base->filter_count ++ ] = filter;
 350                                 mlt_events_fire( properties, "service-changed", NULL );
 351                                 mlt_events_listen( props, this, "service-changed", ( mlt_listener )mlt_service_filter_changed );
 352                                 mlt_events_listen( props, this, "property-changed", ( mlt_listener )mlt_service_filter_changed );
 353                         }
 354                         else
 355                         {
 356                                 error = 2;
 357                         }
 358                 }
 359         }
 360         return error;
 361 }
 362
 363 /** Detach a filter.
 364 */
 365
 366 int mlt_service_detach( mlt_service this, mlt_filter filter )
 367 {
 368         int error = this == NULL || filter == NULL;
 369         if ( error == 0 )
 370         {
 371                 int i = 0;
 372                 mlt_service_base *base = this->local;
 373                 mlt_properties properties = mlt_service_properties( this );
 374
 375                 for ( i = 0; i < base->filter_count; i ++ )
 376                         if ( base->filters[ i ] == filter )
 377                                 break;
 378
 379                 if ( i < base->filter_count )
 380                 {
 381                         base->filters[ i ] = NULL;
 382                         for ( i ++ ; i < base->filter_count; i ++ )
 383                                 base->filters[ i - 1 ] = base->filters[ i ];
 384                         base->filter_count --;
 385                         mlt_events_disconnect( mlt_filter_properties( filter ), this );
 386                         mlt_filter_close( filter );
 387                         mlt_events_fire( properties, "service-changed", NULL );
 388                 }
 389         }
 390         return error;
 391 }
 392
 393 /** Retrieve a filter.
 394 */
 395
 396 mlt_filter mlt_service_filter( mlt_service this, int index )
 397 {
 398         mlt_filter filter = NULL;
 399         if ( this != NULL )
 400         {
 401                 mlt_service_base *base = this->local;
 402                 if ( index >= 0 && index < base->filter_count )
 403                         filter = base->filters[ index ];
 404         }
 405         return filter;
 406 }
 407
 408 /** Close the service.
 409 */
 410
 411 void mlt_service_close( mlt_service this )
 412 {
 413         if ( this != NULL && mlt_properties_dec_ref( mlt_service_properties( this ) ) <= 0 )
 414         {
 415                 if ( this->close != NULL )
 416                 {
 417                         this->close( this->close_object );
 418                 }
 419                 else
 420                 {
 421                         mlt_service_base *base = this->local;
 422                         int i = 0;
 423                         int count = base->filter_count;
 424                         mlt_events_block( mlt_service_properties( this ), this );
 425                         while( count -- )
 426                                 mlt_service_detach( this, base->filters[ 0 ] );
 427                         free( base->filters );
 428                         for ( i = 0; i < base->count; i ++ )
 429                                 if ( base->in[ i ] != NULL )
 430                                         mlt_service_close( base->in[ i ] );
 431                         this->parent.close = NULL;
 432                         free( base->in );
 433                         free( base );
 434                         mlt_properties_close( &this->parent );
 435                 }
 436         }
 437 }
 438