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_position( props, "in", 0 );
  90                         mlt_properties_set_position( props, "out", 0 );
  91                         mlt_properties_set_position( props, "length", 0 );
  92                         mlt_properties_set_data( props, "multitrack", multitrack, 0, ( mlt_destructor )mlt_multitrack_close, NULL );
  93                         mlt_properties_set_data( props, "field", field, 0, ( mlt_destructor )mlt_field_close, NULL );
  94
  95                         producer->get_frame = producer_get_frame;
  96                         producer->close = ( mlt_destructor )mlt_tractor_close;
  97                         producer->close_object = this;
  98                 }
  99                 else
 100                 {
 101                         free( this );
 102                         this = NULL;
 103                 }
 104         }
 105         return this;
 106 }
 107
 108 /** Get the service object associated to the tractor.
 109 */
 110
 111 mlt_service mlt_tractor_service( mlt_tractor this )
 112 {
 113         return mlt_producer_service( &this->parent );
 114 }
 115
 116 /** Get the producer object associated to the tractor.
 117 */
 118
 119 mlt_producer mlt_tractor_producer( mlt_tractor this )
 120 {
 121         return this != NULL ? &this->parent : NULL;
 122 }
 123
 124 /** Get the properties object associated to the tractor.
 125 */
 126
 127 mlt_properties mlt_tractor_properties( mlt_tractor this )
 128 {
 129         return mlt_producer_properties( &this->parent );
 130 }
 131
 132 /** Get the field this tractor is harvesting.
 133 */
 134
 135 mlt_field mlt_tractor_field( mlt_tractor this )
 136 {
 137         return mlt_properties_get_data( mlt_tractor_properties( this ), "field", NULL );
 138 }
 139
 140 /** Get the multitrack this tractor is pulling.
 141 */
 142
 143 mlt_multitrack mlt_tractor_multitrack( mlt_tractor this )
 144 {
 145         return mlt_properties_get_data( mlt_tractor_properties( this ), "multitrack", NULL );
 146 }
 147
 148 /** Ensure the tractors in/out points match the multitrack.
 149 */
 150
 151 void mlt_tractor_refresh( mlt_tractor this )
 152 {
 153         mlt_multitrack multitrack = mlt_tractor_multitrack( this );
 154         mlt_properties properties = mlt_multitrack_properties( multitrack );
 155         mlt_properties self = mlt_tractor_properties( this );
 156         mlt_multitrack_refresh( multitrack );
 157         mlt_properties_set_position( self, "in", 0 );
 158         mlt_properties_set_position( self, "out", mlt_properties_get_position( properties, "out" ) );
 159         mlt_properties_set_position( self, "length", mlt_properties_get_position( properties, "length" ) );
 160 }
 161
 162 /** Connect the tractor.
 163 */
 164
 165 int mlt_tractor_connect( mlt_tractor this, mlt_service producer )
 166 {
 167         int ret = mlt_service_connect_producer( mlt_tractor_service( this ), producer, 0 );
 168
 169         // This is the producer we're going to connect to
 170         if ( ret == 0 )
 171                 this->producer = producer;
 172
 173         return ret;
 174 }
 175
 176 /** Set the producer for a specific track.
 177 */
 178
 179 int mlt_tractor_set_track( mlt_tractor this, mlt_producer producer, int index )
 180 {
 181         int error = mlt_multitrack_connect( mlt_tractor_multitrack( this ), producer, index );
 182         mlt_tractor_refresh( this );
 183         return error;
 184 }
 185
 186 /** Get the producer for a specific track.
 187 */
 188
 189 mlt_producer mlt_tractor_get_track( mlt_tractor this, int index )
 190 {
 191         return mlt_multitrack_track( mlt_tractor_multitrack( this ), index );
 192 }
 193
 194 static int producer_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 195 {
 196         mlt_properties properties = mlt_frame_properties( this );
 197         mlt_frame frame = mlt_frame_pop_service( this );
 198         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 199         mlt_frame_get_image( frame, buffer, format, width, height, writable );
 200         mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
 201         mlt_properties_set_int( properties, "width", *width );
 202         mlt_properties_set_int( properties, "height", *height );
 203         return 0;
 204 }
 205
 206 static int producer_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 207 {
 208         mlt_properties properties = mlt_frame_properties( this );
 209         mlt_frame frame = mlt_frame_pop_audio( this );
 210         mlt_properties_inherit( mlt_frame_properties( frame ), properties );
 211         mlt_frame_get_audio( frame, buffer, format, frequency, channels, samples );
 212         mlt_properties_set_data( properties, "audio", *buffer, 0, NULL, NULL );
 213         mlt_properties_set_int( properties, "frequency", *frequency );
 214         mlt_properties_set_int( properties, "channels", *channels );
 215         return 0;
 216 }
 217
 218 /** Get the next frame.
 219 */
 220
 221 static int producer_get_frame( mlt_producer parent, mlt_frame_ptr frame, int track )
 222 {
 223         mlt_tractor this = parent->child;
 224
 225         // We only respond to the first track requests
 226         if ( track == 0 && this->producer != NULL )
 227         {
 228                 int i = 0;
 229                 int done = 0;
 230                 mlt_frame temp = NULL;
 231                 int count = 0;
 232
 233                 // Get the properties of the parent producer
 234                 mlt_properties properties = mlt_producer_properties( parent );
 235
 236                 // Try to obtain the multitrack associated to the tractor
 237                 mlt_multitrack multitrack = mlt_properties_get_data( properties, "multitrack", NULL );
 238
 239                 // Or a specific producer
 240                 mlt_producer producer = mlt_properties_get_data( properties, "producer", NULL );
 241
 242                 // If we don't have one, we're in trouble...
 243                 if ( multitrack != NULL )
 244                 {
 245                         // Used to garbage collect all frames
 246                         char label[ 30 ];
 247
 248                         // Get the id of the tractor
 249                         char *id = mlt_properties_get( properties, "_unique_id" );
 250
 251                         // Will be used to store the frame properties object
 252                         mlt_properties frame_properties = NULL;
 253
 254                         // We'll store audio and video frames to use here
 255                         mlt_frame audio = NULL;
 256                         mlt_frame video = NULL;
 257
 258                         // Get the multitrack's producer
 259                         mlt_producer target = mlt_multitrack_producer( multitrack );
 260                         mlt_producer_seek( target, mlt_producer_frame( parent ) );
 261                         mlt_producer_set_speed( target, mlt_producer_get_speed( parent ) );
 262
 263                         // We will create one frame and attach everything to it
 264                         *frame = mlt_frame_init( );
 265
 266                         // Get the properties of the frame
 267                         frame_properties = mlt_frame_properties( *frame );
 268
 269                         // Loop through each of the tracks we're harvesting
 270                         for ( i = 0; !done; i ++ )
 271                         {
 272                                 // Get a frame from the producer
 273                                 mlt_service_get_frame( this->producer, &temp, i );
 274
 275                                 // Check for last track
 276                                 done = mlt_properties_get_int( mlt_frame_properties( temp ), "last_track" );
 277
 278                                 // We store all frames with a destructor on the output frame
 279                                 sprintf( label, "_%s_%d", id, count ++ );
 280                                 mlt_properties_set_data( frame_properties, label, temp, 0, ( mlt_destructor )mlt_frame_close, NULL );
 281
 282                                 // Pick up first video and audio frames
 283                                 if ( !done && !mlt_frame_is_test_audio( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 2 ) )
 284                                         audio = temp;
 285                                 if ( !done && !mlt_frame_is_test_card( temp ) && !( mlt_properties_get_int( mlt_frame_properties( temp ), "hide" ) & 1 ) )
 286                                         video = temp;
 287                         }
 288
 289                         // Now stack callbacks
 290                         if ( audio != NULL )
 291                         {
 292                                 mlt_frame_push_audio( *frame, audio );
 293                                 ( *frame )->get_audio = producer_get_audio;
 294                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( audio ) );
 295                         }
 296
 297                         if ( video != NULL )
 298                         {
 299                                 mlt_frame_push_service( *frame, video );
 300                                 mlt_frame_push_service( *frame, producer_get_image );
 301                                 mlt_properties_inherit( mlt_frame_properties( *frame ), mlt_frame_properties( video ) );
 302                         }
 303
 304                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_audio", audio == NULL );
 305                         mlt_properties_set_int( mlt_frame_properties( *frame ), "test_image", video == NULL );
 306                 }
 307                 else if ( producer != NULL )
 308                 {
 309                         mlt_producer_seek( producer, mlt_producer_frame( parent ) );
 310                         mlt_producer_set_speed( producer, mlt_producer_get_speed( parent ) );
 311                         mlt_service_get_frame( this->producer, frame, track );
 312                 }
 313                 else
 314                 {
 315                         fprintf( stderr, "tractor without a multitrack!!\n" );
 316                         mlt_service_get_frame( this->producer, frame, track );
 317                 }
 318
 319                 // Prepare the next frame
 320                 mlt_producer_prepare_next( parent );
 321
 322                 // Indicate our found status
 323                 return 0;
 324         }
 325         else
 326         {
 327                 // Generate a test card
 328                 *frame = mlt_frame_init( );
 329                 return 0;
 330         }
 331 }
 332
 333 /** Close the tractor.
 334 */
 335
 336 void mlt_tractor_close( mlt_tractor this )
 337 {
 338         if ( this != NULL && mlt_properties_dec_ref( mlt_tractor_properties( this ) ) <= 0 )
 339         {
 340                 this->parent.close = NULL;
 341                 mlt_producer_close( &this->parent );
 342                 free( this );
 343         }
 344 }
 345