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

   1 /*
   2  * mlt_tractor.c -- tractor service class
   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
  23 #include "mlt_tractor.h"
  24 #include "mlt_frame.h"
  25 #include "mlt_multitrack.h"
  26
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29
  30 /** Private structure.
  31 */
  32
  33 struct mlt_tractor_s
  34 {
  35         struct mlt_producer_s parent;
  36         mlt_service producer;
  37 };
  38
  39 /** Forward references to static methods.
  40 */
  41
  42 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int track );
  43
  44 /** Constructor for the tractor.
  45
  46         TODO: thread this service...
  47 */
  48
  49 mlt_tractor mlt_tractor_init( )
  50 {
  51         mlt_tractor this = calloc( sizeof( struct mlt_tractor_s ), 1 );
  52         if ( this != NULL )
  53         {
  54                 mlt_producer producer = &this->parent;
  55                 if ( mlt_producer_init( producer, this ) == 0 )
  56                 {
  57                         producer->get_frame = producer_get_frame;
  58                         mlt_properties_set( mlt_producer_properties( producer ), "resource", "<tractor>" );
  59                 }
  60                 else
  61                 {
  62                         free( this );
  63                         this = NULL;
  64                 }
  65         }
  66         return this;
  67 }
  68
  69 /** Get the service object associated to the tractor.
  70 */
  71
  72 mlt_service mlt_tractor_service( mlt_tractor this )
  73 {
  74         return mlt_producer_service( &this->parent );
  75 }
  76
  77 /** Get the producer object associated to the tractor.
  78 */
  79
  80 mlt_producer mlt_tractor_producer( mlt_tractor this )
  81 {
  82         return &this->parent;
  83 }
  84
  85 /** Get the properties object associated to the tractor.
  86 */
  87
  88 mlt_properties mlt_tractor_properties( mlt_tractor this )
  89 {
  90         return mlt_producer_properties( &this->parent );
  91 }
  92
  93 /** Connect the tractor.
  94 */
  95
  96 int mlt_tractor_connect( mlt_tractor this, mlt_service producer )
  97 {
  98         int ret = mlt_service_connect_producer( mlt_tractor_service( this ), producer, 0 );
  99
 100         // This is the producer we're going to connect to
 101         if ( ret == 0 )
 102                 this->producer = producer;
 103
 104         return ret;
 105 }
 106
 107 /** Get the next frame.
 108
 109         TODO: This should be reading a pump being populated by the thread...
 110 */
 111
 112 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int track )
 113 {
 114         mlt_tractor this = parent->child;
 115
 116         // We only respond to the first track requests
 117         if ( track == 0 && this->producer != NULL )
 118         {
 119                 int i = 0;
 120                 int looking = 1;
 121                 int done = 0;
 122                 mlt_frame temp = NULL;
 123                 mlt_frame store[ 10 ];
 124                 int count = 0;
 125
 126                 // Get the properties of the parent producer
 127                 mlt_properties properties = mlt_producer_properties( parent );
 128
 129                 // Try to obtain the multitrack associated to the tractor
 130                 mlt_multitrack multitrack = mlt_properties_get_data( properties, "multitrack", NULL );
 131
 132                 // If we don't have one, we're in trouble...
 133                 if ( multitrack != NULL )
 134                 {
 135                         mlt_producer target = mlt_multitrack_producer( multitrack );
 136                         mlt_producer_seek( target, mlt_producer_frame( parent ) );
 137                         mlt_producer_set_speed( target, mlt_producer_get_speed( parent ) );
 138                         //mlt_producer_set_in_and_out( parent, mlt_producer_get_in( target ), mlt_producer_get_out( target ) );
 139                 }
 140                 else
 141                 {
 142                         fprintf( stderr, "tractor without a multitrack!!\n" );
 143                 }
 144
 145                 // Loop through each of the tracks we're harvesting
 146                 for ( i = 0; !done; i ++ )
 147                 {
 148                         // Get a frame from the producer
 149                         mlt_service_get_frame( this->producer, &temp, i );
 150
 151                         // Check for last track
 152                         done = mlt_properties_get_int( mlt_frame_properties( temp ), "last_track" );
 153
 154                         // Handle the frame
 155                         if ( done && looking )
 156                         {
 157                                 // Use this as output if we don't have one already
 158                                 *frame = temp;
 159                         }
 160                         else if ( ( !mlt_frame_is_test_card( temp ) || !mlt_frame_is_test_audio( temp ) ) && looking &&
 161                                             mlt_producer_frame( parent ) == mlt_frame_get_position( temp ) )
 162                         {
 163                                 *frame = temp;
 164                                 looking = 0;
 165                         }
 166                         else
 167                         {
 168                                 // We store all other frames for now
 169                                 store[ count ++ ] = temp;
 170                         }
 171                 }
 172
 173                 // Now place all the unused frames on to the properties (will be destroyed automatically)
 174                 while ( count -- )
 175                 {
 176                         mlt_properties frame_properties = mlt_frame_properties( *frame );
 177                         char label[ 30 ];
 178                         sprintf( label, "tractor_%d", count );
 179                         mlt_properties_set_data( frame_properties, label, store[ count ], 0, ( mlt_destructor )mlt_frame_close, NULL );
 180                 }
 181
 182                 // Prepare the next frame
 183                 mlt_producer_prepare_next( parent );
 184
 185                 // Indicate our found status
 186                 return 0;
 187         }
 188         else
 189         {
 190                 // Generate a test card
 191                 *frame = mlt_frame_init( );
 192                 return 0;
 193         }
 194 }
 195
 196 /** Close the tractor.
 197 */
 198
 199 void mlt_tractor_close( mlt_tractor this )
 200 {
 201         mlt_producer_close( &this->parent );
 202         free( this );
 203 }
 204