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

   1 /*
   2  * mlt_producer.c -- abstraction for all producer services
   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 #include "mlt_producer.h"
  23 #include "mlt_factory.h"
  24 #include "mlt_frame.h"
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <math.h>
  29
  30 /** Forward references.
  31 */
  32
  33 static int producer_get_frame( mlt_service this, mlt_frame_ptr frame, int index );
  34
  35 /** Constructor
  36 */
  37
  38 int mlt_producer_init( mlt_producer this, void *child )
  39 {
  40         // Check that we haven't received NULL
  41         int error = this == NULL;
  42
  43         // Continue if no error
  44         if ( error == 0 )
  45         {
  46                 // Initialise the producer
  47                 memset( this, 0, sizeof( struct mlt_producer_s ) );
  48
  49                 // Associate with the child
  50                 this->child = child;
  51
  52                 // Initialise the service
  53                 if ( mlt_service_init( &this->parent, this ) == 0 )
  54                 {
  55                         // Get the normalisation preference
  56                         char *normalisation = mlt_environment( "MLT_NORMALISATION" );
  57
  58                         // The parent is the service
  59                         mlt_service parent = &this->parent;
  60
  61                         // Get the properties of the parent
  62                         mlt_properties properties = mlt_service_properties( parent );
  63
  64                         // Set the default properties
  65                         mlt_properties_set( properties, "mlt_type", "mlt_producer" );
  66                         mlt_properties_set_position( properties, "_position", 0.0 );
  67                         mlt_properties_set_double( properties, "_frame", 0 );
  68                         if ( normalisation == NULL || strcmp( normalisation, "NTSC" ) )
  69                         {
  70                                 mlt_properties_set_double( properties, "fps", 25.0 );
  71                                 mlt_properties_set_double( properties, "aspect_ratio", 72.0 / 79.0 );
  72                         }
  73                         else
  74                         {
  75                                 mlt_properties_set_double( properties, "fps", 30000.0 / 1001.0 );
  76                                 mlt_properties_set_double( properties, "aspect_ratio", 128.0 / 117.0 );
  77                         }
  78                         mlt_properties_set_double( properties, "_speed", 1.0 );
  79                         mlt_properties_set_position( properties, "in", 0 );
  80                         mlt_properties_set_position( properties, "out", 14999 );
  81                         mlt_properties_set_position( properties, "length", 15000 );
  82                         mlt_properties_set( properties, "eof", "pause" );
  83                         mlt_properties_set( properties, "resource", "<producer>" );
  84
  85                         // Override service get_frame
  86                         parent->get_frame = producer_get_frame;
  87                 }
  88         }
  89
  90         return error;
  91 }
  92
  93 /** Create a new producer.
  94 */
  95
  96 mlt_producer mlt_producer_new( )
  97 {
  98         mlt_producer this = malloc( sizeof( struct mlt_producer_s ) );
  99         mlt_producer_init( this, NULL );
 100         return this;
 101 }
 102
 103 /** Get the parent service object.
 104 */
 105
 106 mlt_service mlt_producer_service( mlt_producer this )
 107 {
 108         return this != NULL ? &this->parent : NULL;
 109 }
 110
 111 /** Get the producer properties.
 112 */
 113
 114 mlt_properties mlt_producer_properties( mlt_producer this )
 115 {
 116         return mlt_service_properties( &this->parent );
 117 }
 118
 119 /** Seek to a specified position.
 120 */
 121
 122 int mlt_producer_seek( mlt_producer this, mlt_position position )
 123 {
 124         // Determine eof handling
 125         char *eof = mlt_properties_get( mlt_producer_properties( this ), "eof" );
 126         int use_points = 1 - mlt_properties_get_int( mlt_producer_properties( this ), "ignore_points" );
 127
 128         // Check bounds
 129         if ( position < 0 )
 130         {
 131                 position = 0;
 132         }
 133         else if ( use_points && !strcmp( eof, "pause" ) && position >= mlt_producer_get_playtime( this ) )
 134         {
 135                 mlt_producer_set_speed( this, 0 );
 136                 position = mlt_producer_get_playtime( this ) - 1;
 137         }
 138         else if ( use_points && !strcmp( eof, "loop" ) && position >= mlt_producer_get_playtime( this ) )
 139         {
 140                 position = position % mlt_producer_get_playtime( this );
 141         }
 142
 143         // Set the position
 144         mlt_properties_set_position( mlt_producer_properties( this ), "_position", position );
 145
 146         // Calculate the absolute frame
 147         mlt_properties_set_position( mlt_producer_properties( this ), "_frame", use_points * mlt_producer_get_in( this ) + position );
 148
 149         return 0;
 150 }
 151
 152 /** Get the current position (relative to in point).
 153 */
 154
 155 mlt_position mlt_producer_position( mlt_producer this )
 156 {
 157         return mlt_properties_get_position( mlt_producer_properties( this ), "_position" );
 158 }
 159
 160 /** Get the current position (relative to start of producer).
 161 */
 162
 163 mlt_position mlt_producer_frame( mlt_producer this )
 164 {
 165         return mlt_properties_get_position( mlt_producer_properties( this ), "_frame" );
 166 }
 167
 168 /** Set the playing speed.
 169 */
 170
 171 int mlt_producer_set_speed( mlt_producer this, double speed )
 172 {
 173         return mlt_properties_set_double( mlt_producer_properties( this ), "_speed", speed );
 174 }
 175
 176 /** Get the playing speed.
 177 */
 178
 179 double mlt_producer_get_speed( mlt_producer this )
 180 {
 181         return mlt_properties_get_double( mlt_producer_properties( this ), "_speed" );
 182 }
 183
 184 /** Get the frames per second.
 185 */
 186
 187 double mlt_producer_get_fps( mlt_producer this )
 188 {
 189         return mlt_properties_get_double( mlt_producer_properties( this ), "fps" );
 190 }
 191
 192 /** Set the in and out points.
 193 */
 194
 195 int mlt_producer_set_in_and_out( mlt_producer this, mlt_position in, mlt_position out )
 196 {
 197         // Correct ins and outs if necessary
 198         if ( in < 0 )
 199                 in = 0;
 200         else if ( in > mlt_producer_get_length( this ) )
 201                 in = mlt_producer_get_length( this );
 202
 203         if ( out < 0 )
 204                 out = 0;
 205         else if ( out > mlt_producer_get_length( this ) )
 206                 out = mlt_producer_get_length( this );
 207
 208         // Swap ins and outs if wrong
 209         if ( out < in )
 210         {
 211                 mlt_position t = in;
 212                 in = out;
 213                 out = t;
 214         }
 215
 216         // Set the values
 217         mlt_properties_set_position( mlt_producer_properties( this ), "in", in );
 218         mlt_properties_set_position( mlt_producer_properties( this ), "out", out );
 219
 220         return 0;
 221 }
 222
 223 /** Get the in point.
 224 */
 225
 226 mlt_position mlt_producer_get_in( mlt_producer this )
 227 {
 228         return mlt_properties_get_position( mlt_producer_properties( this ), "in" );
 229 }
 230
 231 /** Get the out point.
 232 */
 233
 234 mlt_position mlt_producer_get_out( mlt_producer this )
 235 {
 236         return mlt_properties_get_position( mlt_producer_properties( this ), "out" );
 237 }
 238
 239 /** Get the total play time.
 240 */
 241
 242 mlt_position mlt_producer_get_playtime( mlt_producer this )
 243 {
 244         return mlt_producer_get_out( this ) - mlt_producer_get_in( this ) + 1;
 245 }
 246
 247 /** Get the total length of the producer.
 248 */
 249
 250 mlt_position mlt_producer_get_length( mlt_producer this )
 251 {
 252         return mlt_properties_get_position( mlt_producer_properties( this ), "length" );
 253 }
 254
 255 /** Prepare for next frame.
 256 */
 257
 258 void mlt_producer_prepare_next( mlt_producer this )
 259 {
 260         mlt_producer_seek( this, mlt_producer_position( this ) + mlt_producer_get_speed( this ) );
 261 }
 262
 263 /** Get a frame.
 264 */
 265
 266 static int producer_get_frame( mlt_service service, mlt_frame_ptr frame, int index )
 267 {
 268         int result = 1;
 269         mlt_producer this = service->child;
 270
 271         // Determine eof handling
 272         char *eof = mlt_properties_get( mlt_producer_properties( this ), "eof" );
 273
 274         // A properly instatiated producer will have a get_frame method...
 275         if ( this->get_frame == NULL || ( !strcmp( eof, "continue" ) && mlt_producer_position( this ) > mlt_producer_get_out( this ) ) )
 276         {
 277                 // Generate a test frame
 278                 *frame = mlt_frame_init( );
 279
 280                 // Set the position
 281                 result = mlt_frame_set_position( *frame, mlt_producer_position( this ) );
 282
 283                 // Mark as a test card
 284                 mlt_properties_set_int( mlt_frame_properties( *frame ), "test_image", 1 );
 285                 mlt_properties_set_int( mlt_frame_properties( *frame ), "test_audio", 1 );
 286
 287                 // Calculate the next position
 288                 mlt_producer_prepare_next( this );
 289         }
 290         else
 291         {
 292                 // Get the frame from the implementation
 293                 result = this->get_frame( this, frame, index );
 294         }
 295
 296         // Copy the fps and speed of the producer onto the frame
 297         mlt_properties properties = mlt_frame_properties( *frame );
 298         mlt_properties_set_double( properties, "fps", mlt_producer_get_fps( this ) );
 299         double speed = mlt_producer_get_speed( this );
 300         mlt_properties_set_double( properties, "_speed", speed );
 301         mlt_properties_set_int( properties, "test_audio", mlt_frame_is_test_audio( *frame ) );
 302         mlt_properties_set_int( properties, "test_image", mlt_frame_is_test_card( *frame ) );
 303
 304         return 0;
 305 }
 306
 307 /** Close the producer.
 308 */
 309
 310 void mlt_producer_close( mlt_producer this )
 311 {
 312         if ( this->close != NULL )
 313                 this->close( this );
 314         else
 315                 mlt_service_close( &this->parent );
 316 }