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

   1 /**
   2  * \file mlt_producer.h
   3  * \brief abstraction for all producer services
   4  *
   5  * Copyright (C) 2003-2008 Ushodaya Enterprises Limited
   6  * \author Charles Yates <charles.yates@pandora.be>
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with this library; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21  */
  22
  23 #ifndef _MLT_PRODUCER_H_
  24 #define _MLT_PRODUCER_H_
  25
  26 #include "mlt_service.h"
  27 #include "mlt_filter.h"
  28
  29 /** \brief Producer abstract service class
  30  *
  31  * A producer is a service that generates audio, video, and metadata.
  32  * Some day it may also generate text (subtitles). This is not to say
  33  * a producer "synthesizes," rather that is an origin of data within the
  34  * service network - that could be through synthesis or reading a stream.
  35  *
  36  * \extends mlt_service
  37  * \event \em producer-changed
  38  * \properties \em mlt_type the name of the service subclass, e.g. mlt_producer
  39  * \properties \em mlt_service the name of a producer subclass
  40  * \properties \em _position the current position of the play head, relative to the in point
  41  * \properties \em _frame the current position of the play head, relative to the beginning of the resource
  42  * \properties \em _speed the current speed factor, where 1.0 is normal
  43  * \properties \em aspect_ratio sample aspect ratio
  44  * \properties \em length the duration of the cut in frames
  45  * \properties \em eof the end-of-file behavior, one of: pause, continue, loop
  46  * \properties \em resource the file name, stream address, or the class name in angle brackets
  47  * \properties \em _cut set if this producer is a "cut" producer
  48  * \properties \em mlt_mix stores the data for a "mix" producer
  49  * \properties \em _cut_parent holds a reference to the cut's parent producer
  50  * \properties \em ignore_points Set this to temporarily disable the in and out points.
  51  * \properties \em use_clone holds a reference to a clone's producer, as created by mlt_producer_optimise
  52  * \properties \em _clone is the index of the clone in the list of clones stored on the clone's producer
  53  * \properties \em _clones is the number of clones of the producer, as created by mlt_producer_optimise
  54  * \properties \em _clone.{N} holds a reference to the N'th clone of the producer, as created by mlt_producer_optimise
  55  * \properties \em meta.* holds metadata - there is a loose taxonomy to be defined
  56  * \properties \em set.* holds properties to set on a frame produced
  57  * \todo define the media metadata taxonomy
  58  */
  59
  60 struct mlt_producer_s
  61 {
  62         /** A producer is a service. */
  63         struct mlt_service_s parent;
  64
  65         /** Get a frame of data (virtual function).
  66          *
  67          * \param mlt_producer a producer
  68          * \param mlt_frame_ptr a frame pointer by reference
  69          * \param int an index
  70          * \return true if there was an error
  71          */
  72         int ( *get_frame )( mlt_producer, mlt_frame_ptr, int );
  73
  74         /** the destructor virtual function */
  75         mlt_destructor close;
  76         void *close_object; /**< the object supplied to the close virtual function */
  77
  78         void *local; /**< \private instance object */
  79         void *child; /**< \private the object of a subclass */
  80 };
  81
  82 /*
  83  *  Public final methods
  84  */
  85
  86 #define MLT_PRODUCER_SERVICE( producer )        ( &( producer )->parent )
  87 #define MLT_PRODUCER_PROPERTIES( producer )     MLT_SERVICE_PROPERTIES( MLT_PRODUCER_SERVICE( producer ) )
  88
  89 extern int mlt_producer_init( mlt_producer self, void *child );
  90 extern mlt_producer mlt_producer_new( );
  91 extern mlt_service mlt_producer_service( mlt_producer self );
  92 extern mlt_properties mlt_producer_properties( mlt_producer self );
  93 extern int mlt_producer_seek( mlt_producer self, mlt_position position );
  94 extern mlt_position mlt_producer_position( mlt_producer self );
  95 extern mlt_position mlt_producer_frame( mlt_producer self );
  96 extern int mlt_producer_set_speed( mlt_producer self, double speed );
  97 extern double mlt_producer_get_speed( mlt_producer self );
  98 extern double mlt_producer_get_fps( mlt_producer self );
  99 extern int mlt_producer_set_in_and_out( mlt_producer self, mlt_position in, mlt_position out );
 100 extern int mlt_producer_clear( mlt_producer self );
 101 extern mlt_position mlt_producer_get_in( mlt_producer self );
 102 extern mlt_position mlt_producer_get_out( mlt_producer self );
 103 extern mlt_position mlt_producer_get_playtime( mlt_producer self );
 104 extern mlt_position mlt_producer_get_length( mlt_producer self );
 105 extern void mlt_producer_prepare_next( mlt_producer self );
 106 extern int mlt_producer_attach( mlt_producer self, mlt_filter filter );
 107 extern int mlt_producer_detach( mlt_producer self, mlt_filter filter );
 108 extern mlt_filter mlt_producer_filter( mlt_producer self, int index );
 109 extern mlt_producer mlt_producer_cut( mlt_producer self, int in, int out );
 110 extern int mlt_producer_is_cut( mlt_producer self );
 111 extern int mlt_producer_is_mix( mlt_producer self );
 112 extern int mlt_producer_is_blank( mlt_producer self );
 113 extern mlt_producer mlt_producer_cut_parent( mlt_producer self );
 114 extern int mlt_producer_optimise( mlt_producer self );
 115 extern void mlt_producer_close( mlt_producer self );
 116
 117 #endif