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 #include <string.h>
  30
  31 /** Private structure.
  32 */
  33
  34 struct mlt_tractor_s
  35 {
  36         struct mlt_producer_s parent;
  37         mlt_service producer;
  38 };
  39
  40 /** Forward references to static methods.
  41 */
  42
  43 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int track );
  44 static void producer_close( mlt_producer this );
  45
  46 /** Constructor for the tractor.
  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                         mlt_properties_set( mlt_producer_properties( producer ), "resource", "<tractor>" );
  58                         mlt_properties_set( mlt_producer_properties( producer ), "mlt_type", "mlt_producer" );
  59                         mlt_properties_set( mlt_producer_properties( producer ), "mlt_service", "tractor" );
  60
  61                         producer->get_frame = producer_get_frame;
  62                         producer->close = producer_close;
  63                 }
  64                 else
  65                 {
  66                         free( this );
  67                         this = NULL;
  68                 }
  69         }
  70         return this;
  71 }
  72
  73 /** Get the service object associated to the tractor.
  74 */
  75
  76 mlt_service mlt_tractor_service( mlt_tractor this )
  77 {
  78         return mlt_producer_service( &this->parent );
  79 }
  80
  81 /** Get the producer object associated to the tractor.
  82 */
  83
  84 mlt_producer mlt_tractor_producer( mlt_tractor this )
  85 {
  86         return &this->parent;
  87 }
  88
  89 /** Get the properties object associated to the tractor.
  90 */
  91
  92 mlt_properties mlt_tractor_properties( mlt_tractor this )
  93 {
  94         return mlt_producer_properties( &this->parent );
  95 }
  96
  97 /** Connect the tractor.
  98 */
  99
 100 int mlt_tractor_connect( mlt_tractor this, mlt_service producer )
 101 {
 102         int ret = mlt_service_connect_producer( mlt_tractor_service( this ), producer, 0 );
 103
 104         // This is the producer we're going to connect to
 105         if ( ret == 0 )
 106                 this->producer = producer;
 107
 108         return ret;
 109 }
 110
 111 static int producer_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 112 {
 113         mlt_properties properties = mlt_frame_properties( this );
 114         mlt_frame frame = mlt_frame_pop_service( this );
 115         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 116         mlt_frame_get_image( frame, buffer, format, width, height, writable );
 117         mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
 118         mlt_properties_set_int( properties, "width", *width );
 119         mlt_properties_set_int( properties, "height", *height );
 120         return 0;
 121 }
 122
 123 static int producer_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 124 {
 125         mlt_properties properties = mlt_frame_properties( this );
 126         mlt_frame frame = mlt_frame_pop_audio( this );
 127         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 128         mlt_frame_get_audio( frame, buffer, format, frequency, channels, samples );
 129         mlt_properties_set_data( properties, "audio", *buffer, 0, NULL, NULL );
 130         mlt_properties_set_int( properties, "frequency", *frequency );
 131         mlt_properties_set_int( properties, "channels", *channels );
 132         return 0;
 133 }
 134
 135 /** Get the next frame.
 136 */
 137
 138 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int track )
 139 {
 140         mlt_tractor this = parent->child;
 141
 142         // We only respond to the first track requests
 143         if ( track == 0 && this->producer != NULL )
 144         {
 145                 int i = 0;
 146                 int done = 0;
 147                 mlt_frame temp = NULL;
 148                 int count = 0;
 149
 150                 // Get the properties of the parent producer
 151                 mlt_properties properties = mlt_producer_properties( parent );
 152
 153                 // Try to obtain the multitrack associated to the tractor
 154                 mlt_multitrack multitrack = mlt_properties_get_data( properties, "multitrack", NULL );
 155
 156                 // Or a specific producer
 157                 mlt_producer producer = mlt_properties_get_data( properties, "producer", NULL );
 158
 159                 // If we don't have one, we're in trouble...
 160                 if ( multitrack != NULL )
 161                 {
 162                         // Used to garbage collect all frames
 163                         char label[ 30 ];
 164
 165                         // Get the id of the tractor
 166                         char *id = mlt_properties_get( properties, "_unique_id" );
 167
 168                         // Will be used to store the frame properties object
 169                         mlt_properties frame_properties = NULL;
 170
 171                         // We'll store audio and video frames to use here
 172                         mlt_frame audio = NULL;
 173                         mlt_frame video = NULL;
 174
 175                         // Get the multitrack's producer
 176                         mlt_producer target = mlt_multitrack_producer( multitrack );
 177                         mlt_producer_seek( target, mlt_producer_frame( parent ) );
 178                         mlt_producer_set_speed( target, mlt_producer_get_speed( parent ) );
 179
 180                         // We will create one frame and attach everything to it
 181                         *frame = mlt_frame_init( );
 182
 183                         // Get the properties of the frame
 184                         frame_properties = mlt_frame_properties( *frame );
 185
 186                         // Loop through each of the tracks we're harvesting
 187                         for ( i = 0; !done; i ++ )
 188                         {
 189                                 // Get a frame from the producer
 190                                 mlt_service_get_frame( this->producer, &temp, i );
 191
 192                                 // Check for last track
 193                                 done = mlt_properties_get_int( mlt_frame_properties( temp ), "last_track" );
 194
 195                                 // We store all frames with a destructor on the output frame
 196                                 sprintf( label, "_%s_%d", id, count ++ );
 197                                 mlt_properties_set_data( frame_properties, label, temp, 0, ( mlt_destructor )mlt_frame_close, NULL );
 198
 199                                 // Pick up first video and audio frames
 200                                 if ( !done && !mlt_frame_is_test_audio( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 2 ) )
 201                                         audio = temp;
 202                                 if ( !done && !mlt_frame_is_test_card( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 1 ) )
 203                                         video = temp;
 204                         }
 205
 206                         // Now stack callbacks
 207                         if ( audio != NULL )
 208                         {
 209                                 mlt_frame_push_audio( *frame, audio );
 210                                 ( *frame )->get_audio = producer_get_audio;
 211                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( audio ) );
 212                         }
 213
 214                         if ( video != NULL )
 215                         {
 216                                 mlt_frame_push_service( *frame, video );
 217                                 mlt_frame_push_service( *frame, producer_get_image );
 218                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( video ) );
 219                         }
 220
 221                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_audio", audio == NULL );
 222                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_image", video == NULL );
 223                 }
 224                 else if ( producer != NULL )
 225                 {
 226                         mlt_producer_seek( producer, mlt_producer_frame( parent ) );
 227                         mlt_producer_set_speed( producer, mlt_producer_get_speed( parent ) );
 228                         mlt_service_get_frame( this->producer, frame, track );
 229                 }
 230                 else
 231                 {
 232                         fprintf( stderr, "tractor without a multitrack!!\n" );
 233                         mlt_service_get_frame( this->producer, frame, track );
 234                 }
 235
 236                 // Prepare the next frame
 237                 mlt_producer_prepare_next( parent );
 238
 239                 // Indicate our found status
 240                 return 0;
 241         }
 242         else
 243         {
 244                 // Generate a test card
 245                 *frame = mlt_frame_init( );
 246                 return 0;
 247         }
 248 }
 249
 250 /** Close the tractor.
 251 */
 252
 253 void mlt_tractor_close( mlt_tractor this )
 254 {
 255         this->parent.close = NULL;
 256         mlt_producer_close( &this->parent );
 257         free( this );
 258 }
 259
 260 /** Close the producer.
 261 */
 262
 263 static void producer_close( mlt_producer this )
 264 {
 265         mlt_tractor_close( this->child );
 266 }
 267