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 #include "mlt_field.h"
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31
  32 /** Private structure.
  33 */
  34
  35 struct mlt_tractor_s
  36 {
  37         struct mlt_producer_s parent;
  38         mlt_service producer;
  39 };
  40
  41 /** Forward references to static methods.
  42 */
  43
  44 static int producer_get_frame( mlt_producer this, mlt_frame_ptr frame, int track );
  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 = ( mlt_destructor )mlt_tractor_close;
  63                         producer->close_object = this;
  64                 }
  65                 else
  66                 {
  67                         free( this );
  68                         this = NULL;
  69                 }
  70         }
  71         return this;
  72 }
  73
  74 mlt_tractor mlt_tractor_new( )
  75 {
  76         mlt_tractor this = calloc( sizeof( struct mlt_tractor_s ), 1 );
  77         if ( this != NULL )
  78         {
  79                 mlt_producer producer = &this->parent;
  80                 if ( mlt_producer_init( producer, this ) == 0 )
  81                 {
  82                         mlt_multitrack multitrack = mlt_multitrack_init( );
  83                         mlt_field field = mlt_field_new( multitrack, this );
  84                         mlt_properties props = mlt_producer_properties( producer );
  85
  86                         mlt_properties_set( props, "resource", "<tractor>" );
  87                         mlt_properties_set( props, "mlt_type", "mlt_producer" );
  88                         mlt_properties_set( props, "mlt_service", "tractor" );
  89                         mlt_properties_set_data( props, "multitrack", multitrack, 0, ( mlt_destructor )mlt_multitrack_close, NULL );
  90                         mlt_properties_set_data( props, "field", field, 0, ( mlt_destructor )mlt_field_close, NULL );
  91
  92                         producer->get_frame = producer_get_frame;
  93                         producer->close = ( mlt_destructor )mlt_tractor_close;
  94                         producer->close_object = this;
  95                 }
  96                 else
  97                 {
  98                         free( this );
  99                         this = NULL;
 100                 }
 101         }
 102         return this;
 103 }
 104
 105 /** Get the service object associated to the tractor.
 106 */
 107
 108 mlt_service mlt_tractor_service( mlt_tractor this )
 109 {
 110         return mlt_producer_service( &this->parent );
 111 }
 112
 113 /** Get the producer object associated to the tractor.
 114 */
 115
 116 mlt_producer mlt_tractor_producer( mlt_tractor this )
 117 {
 118         return this != NULL ? &this->parent : NULL;
 119 }
 120
 121 /** Get the properties object associated to the tractor.
 122 */
 123
 124 mlt_properties mlt_tractor_properties( mlt_tractor this )
 125 {
 126         return mlt_producer_properties( &this->parent );
 127 }
 128
 129 /** Get the field this tractor is harvesting.
 130 */
 131
 132 mlt_field mlt_tractor_field( mlt_tractor this )
 133 {
 134         return mlt_properties_get_data( mlt_tractor_properties( this ), "field", NULL );
 135 }
 136
 137 /** Get the multitrack this tractor is pulling.
 138 */
 139
 140 mlt_multitrack mlt_tractor_multitrack( mlt_tractor this )
 141 {
 142         return mlt_properties_get_data( mlt_tractor_properties( this ), "multitrack", NULL );
 143 }
 144
 145 /** Connect the tractor.
 146 */
 147
 148 int mlt_tractor_connect( mlt_tractor this, mlt_service producer )
 149 {
 150         int ret = mlt_service_connect_producer( mlt_tractor_service( this ), producer, 0 );
 151
 152         // This is the producer we're going to connect to
 153         if ( ret == 0 )
 154                 this->producer = producer;
 155
 156         return ret;
 157 }
 158
 159 static int producer_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 160 {
 161         mlt_properties properties = mlt_frame_properties( this );
 162         mlt_frame frame = mlt_frame_pop_service( this );
 163         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 164         mlt_frame_get_image( frame, buffer, format, width, height, writable );
 165         mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
 166         mlt_properties_set_int( properties, "width", *width );
 167         mlt_properties_set_int( properties, "height", *height );
 168         return 0;
 169 }
 170
 171 static int producer_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 172 {
 173         mlt_properties properties = mlt_frame_properties( this );
 174         mlt_frame frame = mlt_frame_pop_audio( this );
 175         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 176         mlt_frame_get_audio( frame, buffer, format, frequency, channels, samples );
 177         mlt_properties_set_data( properties, "audio", *buffer, 0, NULL, NULL );
 178         mlt_properties_set_int( properties, "frequency", *frequency );
 179         mlt_properties_set_int( properties, "channels", *channels );
 180         return 0;
 181 }
 182
 183 /** Get the next frame.
 184 */
 185
 186 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int track )
 187 {
 188         mlt_tractor this = parent->child;
 189
 190         // We only respond to the first track requests
 191         if ( track == 0 && this->producer != NULL )
 192         {
 193                 int i = 0;
 194                 int done = 0;
 195                 mlt_frame temp = NULL;
 196                 int count = 0;
 197
 198                 // Get the properties of the parent producer
 199                 mlt_properties properties = mlt_producer_properties( parent );
 200
 201                 // Try to obtain the multitrack associated to the tractor
 202                 mlt_multitrack multitrack = mlt_properties_get_data( properties, "multitrack", NULL );
 203
 204                 // Or a specific producer
 205                 mlt_producer producer = mlt_properties_get_data( properties, "producer", NULL );
 206
 207                 // If we don't have one, we're in trouble...
 208                 if ( multitrack != NULL )
 209                 {
 210                         // Used to garbage collect all frames
 211                         char label[ 30 ];
 212
 213                         // Get the id of the tractor
 214                         char *id = mlt_properties_get( properties, "_unique_id" );
 215
 216                         // Will be used to store the frame properties object
 217                         mlt_properties frame_properties = NULL;
 218
 219                         // We'll store audio and video frames to use here
 220                         mlt_frame audio = NULL;
 221                         mlt_frame video = NULL;
 222
 223                         // Get the multitrack's producer
 224                         mlt_producer target = mlt_multitrack_producer( multitrack );
 225                         mlt_producer_seek( target, mlt_producer_frame( parent ) );
 226                         mlt_producer_set_speed( target, mlt_producer_get_speed( parent ) );
 227
 228                         // We will create one frame and attach everything to it
 229                         *frame = mlt_frame_init( );
 230
 231                         // Get the properties of the frame
 232                         frame_properties = mlt_frame_properties( *frame );
 233
 234                         // Loop through each of the tracks we're harvesting
 235                         for ( i = 0; !done; i ++ )
 236                         {
 237                                 // Get a frame from the producer
 238                                 mlt_service_get_frame( this->producer, &temp, i );
 239
 240                                 // Check for last track
 241                                 done = mlt_properties_get_int( mlt_frame_properties( temp ), "last_track" );
 242
 243                                 // We store all frames with a destructor on the output frame
 244                                 sprintf( label, "_%s_%d", id, count ++ );
 245                                 mlt_properties_set_data( frame_properties, label, temp, 0, ( mlt_destructor )mlt_frame_close, NULL );
 246
 247                                 // Pick up first video and audio frames
 248                                 if ( !done && !mlt_frame_is_test_audio( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 2 ) )
 249                                         audio = temp;
 250                                 if ( !done && !mlt_frame_is_test_card( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 1 ) )
 251                                         video = temp;
 252                         }
 253
 254                         // Now stack callbacks
 255                         if ( audio != NULL )
 256                         {
 257                                 mlt_frame_push_audio( *frame, audio );
 258                                 ( *frame )->get_audio = producer_get_audio;
 259                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( audio ) );
 260                         }
 261
 262                         if ( video != NULL )
 263                         {
 264                                 mlt_frame_push_service( *frame, video );
 265                                 mlt_frame_push_service( *frame, producer_get_image );
 266                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( video ) );
 267                         }
 268
 269                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_audio", audio == NULL );
 270                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_image", video == NULL );
 271                 }
 272                 else if ( producer != NULL )
 273                 {
 274                         mlt_producer_seek( producer, mlt_producer_frame( parent ) );
 275                         mlt_producer_set_speed( producer, mlt_producer_get_speed( parent ) );
 276                         mlt_service_get_frame( this->producer, frame, track );
 277                 }
 278                 else
 279                 {
 280                         fprintf( stderr, "tractor without a multitrack!!\n" );
 281                         mlt_service_get_frame( this->producer, frame, track );
 282                 }
 283
 284                 // Prepare the next frame
 285                 mlt_producer_prepare_next( parent );
 286
 287                 // Indicate our found status
 288                 return 0;
 289         }
 290         else
 291         {
 292                 // Generate a test card
 293                 *frame = mlt_frame_init( );
 294                 return 0;
 295         }
 296 }
 297
 298 /** Close the tractor.
 299 */
 300
 301 void mlt_tractor_close( mlt_tractor this )
 302 {
 303         if ( this != NULL && mlt_properties_dec_ref( mlt_tractor_properties( this ) ) <= 0 )
 304         {
 305                 this->parent.close = NULL;
 306                 mlt_producer_close( &this->parent );
 307                 free( this );
 308         }
 309 }
 310