research.m1stereo.tv/gitweb/ - melted/blob - src/framework/mlt_transition.h

   1 /**
   2  * \file mlt_transition.h
   3  * \brief abstraction for all transition services
   4  * \see mlt_transition_s
   5  *
   6  * Copyright (C) 2003-2009 Ushodaya Enterprises Limited
   7  * \author Charles Yates <charles.yates@pandora.be>
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #ifndef _MLT_TRANSITION_H_
  25 #define _MLT_TRANSITION_H_
  26
  27 #include "mlt_service.h"
  28
  29 /** \brief Transition abstract service class
  30  *
  31  * A transition may modify the output of a producer based on the output of a second producer.
  32  *
  33  * \extends mlt_service_s
  34  * \properties \em a_track the track index (0-based) of a multitrack of the first producer
  35  * \properties \em b_track the track index (0-based) of a multitrack of the second producer
  36  * \properties \em accepts_blanks a flag to indicate if the transition should accept blank frames
  37  * \properties \em always_active a flag to indicate that the in and out points do not apply
  38  * \properties \em _transition_type 1 for video, 2 for audio
  39  */
  40
  41 struct mlt_transition_s
  42 {
  43         /** We're implementing service here */
  44         struct mlt_service_s parent;
  45
  46         /** public virtual */
  47         void ( *close )( mlt_transition );
  48
  49         /** protected transition method */
  50         mlt_frame ( *process )( mlt_transition, mlt_frame, mlt_frame );
  51
  52         /** Protected */
  53         void *child;
  54
  55         /** track and in/out points */
  56         mlt_service producer;
  57
  58         /** Private */
  59         mlt_frame *frames;
  60         int held;
  61 };
  62
  63 #define MLT_TRANSITION_SERVICE( transition )            ( &( transition )->parent )
  64 #define MLT_TRANSITION_PROPERTIES( transition )         MLT_SERVICE_PROPERTIES( MLT_TRANSITION_SERVICE( transition ) )
  65
  66 extern int mlt_transition_init( mlt_transition self, void *child );
  67 extern mlt_transition mlt_transition_new( );
  68 extern mlt_service mlt_transition_service( mlt_transition self );
  69 extern mlt_properties mlt_transition_properties( mlt_transition self );
  70 extern int mlt_transition_connect( mlt_transition self, mlt_service producer, int a_track, int b_track );
  71 extern void mlt_transition_set_in_and_out( mlt_transition self, mlt_position in, mlt_position out );
  72 extern int mlt_transition_get_a_track( mlt_transition self );
  73 extern int mlt_transition_get_b_track( mlt_transition self );
  74 extern mlt_position mlt_transition_get_in( mlt_transition self );
  75 extern mlt_position mlt_transition_get_out( mlt_transition self );
  76 extern mlt_frame mlt_transition_process( mlt_transition self, mlt_frame a_frame, mlt_frame b_frame );
  77 extern void mlt_transition_close( mlt_transition self );
  78
  79 #endif