research.m1stereo.tv/gitweb/ - melted/blob - src/modules/core/filter_transition.c

   1 /*
   2  * filter_transition.c -- Convert any transition into a filter
   3  * Copyright (C) 2005 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 "filter_transition.h"
  22 #include <framework/mlt_factory.h>
  23 #include <framework/mlt_frame.h>
  24 #include <framework/mlt_transition.h>
  25
  26 /** Get the image via the transition.
  27         NB: Not all transitions will accept a and b frames being the same...
  28 */
  29
  30 static int filter_get_image( mlt_frame this, uint8_t **image, mlt_image_format *format, int *width, int *height, int writable )
  31 {
  32         mlt_transition transition = mlt_frame_pop_service( this );
  33         mlt_transition_process( transition, this, this );
  34         return mlt_frame_get_image( this, image, format, width, height, writable );
  35 }
  36
  37 /** Get the audio via the transition.
  38         NB: Not all transitions will accept a and b frames being the same...
  39 */
  40
  41 static int filter_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
  42 {
  43         // Obtain the transition instance
  44         mlt_transition transition = mlt_frame_pop_audio( this );
  45         mlt_transition_process( transition, this, this );
  46         return mlt_frame_get_audio( this, buffer, format, frequency, channels, samples );
  47 }
  48
  49 /** Filter processing.
  50 */
  51
  52 static mlt_frame filter_process( mlt_filter this, mlt_frame frame )
  53 {
  54         // Obtain the transition instance
  55         mlt_transition transition = mlt_properties_get_data( MLT_FILTER_PROPERTIES( this ), "instance", NULL );
  56
  57         // If we haven't created the instance, do it now
  58         if ( transition == NULL )
  59         {
  60                 char *name = mlt_properties_get( MLT_FILTER_PROPERTIES( this ), "transition" );
  61                 transition = mlt_factory_transition( name, NULL );
  62                 mlt_properties_set_data( MLT_FILTER_PROPERTIES( this ), "instance", transition, 0, ( mlt_destructor )mlt_transition_close, NULL );
  63         }
  64
  65         // We may still not have a transition...
  66         if ( transition != NULL )
  67         {
  68                 // Get the transition type
  69                 int type = mlt_properties_get_int( MLT_TRANSITION_PROPERTIES( transition ), "_transition_type" );
  70
  71                 // Set the basic info
  72                 mlt_properties_set_int( MLT_TRANSITION_PROPERTIES( transition ), "in", mlt_properties_get_int( MLT_FILTER_PROPERTIES( this ), "in" ) );
  73                 mlt_properties_set_int( MLT_TRANSITION_PROPERTIES( transition ), "out", mlt_properties_get_int( MLT_FILTER_PROPERTIES( this ), "out" ) );
  74
  75                 // Refresh with current user values
  76                 mlt_properties_pass( MLT_TRANSITION_PROPERTIES( transition ), MLT_FILTER_PROPERTIES( this ), "transition." );
  77
  78                 if ( type & 1 )
  79                 {
  80                         mlt_frame_push_service( frame, transition );
  81                         mlt_frame_push_get_image( frame, filter_get_image );
  82                 }
  83                 if ( type & 2 )
  84                 {
  85                         mlt_frame_push_audio( frame, transition );
  86                         mlt_frame_push_audio( frame, filter_get_audio );
  87                 }
  88
  89                 if ( type == 0 )
  90                         mlt_properties_debug( MLT_TRANSITION_PROPERTIES( transition ), "unknown transition type", stderr );
  91         }
  92         else
  93         {
  94                 mlt_properties_debug( MLT_FILTER_PROPERTIES( this ), "no transition", stderr );
  95         }
  96
  97         return frame;
  98 }
  99
 100 /** Constructor for the filter.
 101 */
 102
 103 mlt_filter filter_transition_init( char *arg )
 104 {
 105         mlt_filter this = mlt_filter_new( );
 106         if ( this != NULL )
 107         {
 108                 mlt_properties_set( MLT_FILTER_PROPERTIES( this ), "transition", arg );
 109                 this->process = filter_process;
 110         }
 111         return this;
 112 }
 113