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

   1 /*
   2  * mlt_frame.c -- interface for all frame classes
   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_frame.h"
  23 #include "mlt_producer.h"
  24 #include "mlt_factory.h"
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28
  29 /** Constructor for a frame.
  30 */
  31
  32 mlt_frame mlt_frame_init( )
  33 {
  34         // Allocate a frame
  35         mlt_frame this = calloc( sizeof( struct mlt_frame_s ), 1 );
  36
  37         if ( this != NULL )
  38         {
  39                 // Get the normalisation
  40                 char *normalisation = mlt_environment( "MLT_NORMALISATION" );
  41
  42                 // Initialise the properties
  43                 mlt_properties properties = &this->parent;
  44                 mlt_properties_init( properties, this );
  45
  46                 // Set default properties on the frame
  47                 mlt_properties_set_position( properties, "_position", 0.0 );
  48                 mlt_properties_set_data( properties, "image", NULL, 0, NULL, NULL );
  49
  50                 if ( normalisation == NULL || strcmp( normalisation, "NTSC" ) )
  51                 {
  52                         mlt_properties_set_int( properties, "width", 720 );
  53                         mlt_properties_set_int( properties, "height", 576 );
  54                         mlt_properties_set_int( properties, "normalised_width", 720 );
  55                         mlt_properties_set_int( properties, "normalised_height", 576 );
  56                         mlt_properties_set_double( properties, "aspect_ratio", 72.0/79.0 );
  57                 }
  58                 else
  59                 {
  60                         mlt_properties_set_int( properties, "width", 720 );
  61                         mlt_properties_set_int( properties, "height", 480 );
  62                         mlt_properties_set_int( properties, "normalised_width", 720 );
  63                         mlt_properties_set_int( properties, "normalised_height", 480 );
  64                         mlt_properties_set_double( properties, "aspect_ratio", 128.0/117.0 );
  65                 }
  66
  67                 mlt_properties_set_data( properties, "audio", NULL, 0, NULL, NULL );
  68                 mlt_properties_set_data( properties, "alpha", NULL, 0, NULL, NULL );
  69
  70                 // Construct stacks for frames and methods
  71                 this->stack_image = mlt_deque_init( );
  72                 this->stack_audio = mlt_deque_init( );
  73         }
  74
  75         return this;
  76 }
  77
  78 /** Fetch the frames properties.
  79 */
  80
  81 mlt_properties mlt_frame_properties( mlt_frame this )
  82 {
  83         return this != NULL ? &this->parent : NULL;
  84 }
  85
  86 /** Check if we have a way to derive something other than a test card.
  87 */
  88
  89 int mlt_frame_is_test_card( mlt_frame this )
  90 {
  91         return mlt_deque_count( this->stack_image ) == 0 || mlt_properties_get_int( mlt_frame_properties( this ), "test_image" );
  92 }
  93
  94 /** Check if we have a way to derive something than test audio.
  95 */
  96
  97 int mlt_frame_is_test_audio( mlt_frame this )
  98 {
  99         return this->get_audio == NULL || mlt_properties_get_int( mlt_frame_properties( this ), "test_audio" );
 100 }
 101
 102 /** Get the aspect ratio of the frame.
 103 */
 104
 105 double mlt_frame_get_aspect_ratio( mlt_frame this )
 106 {
 107         return mlt_properties_get_double( mlt_frame_properties( this ), "aspect_ratio" );
 108 }
 109
 110 /** Set the aspect ratio of the frame.
 111 */
 112
 113 int mlt_frame_set_aspect_ratio( mlt_frame this, double value )
 114 {
 115         return mlt_properties_set_double( mlt_frame_properties( this ), "aspect_ratio", value );
 116 }
 117
 118 /** Get the position of this frame.
 119 */
 120
 121 mlt_position mlt_frame_get_position( mlt_frame this )
 122 {
 123         return mlt_properties_get_position( mlt_frame_properties( this ), "_position" );
 124 }
 125
 126 /** Set the position of this frame.
 127 */
 128
 129 int mlt_frame_set_position( mlt_frame this, mlt_position value )
 130 {
 131         return mlt_properties_set_position( mlt_frame_properties( this ), "_position", value );
 132 }
 133
 134 /** Stack a get_image callback.
 135 */
 136
 137 int mlt_frame_push_get_image( mlt_frame this, mlt_get_image get_image )
 138 {
 139         return mlt_deque_push_back( this->stack_image, get_image );
 140 }
 141
 142 /** Pop a get_image callback.
 143 */
 144
 145 mlt_get_image mlt_frame_pop_get_image( mlt_frame this )
 146 {
 147         return mlt_deque_pop_back( this->stack_image );
 148 }
 149
 150 /** Push a frame.
 151 */
 152
 153 int mlt_frame_push_frame( mlt_frame this, mlt_frame that )
 154 {
 155         return mlt_deque_push_back( this->stack_image, that );
 156 }
 157
 158 /** Pop a frame.
 159 */
 160
 161 mlt_frame mlt_frame_pop_frame( mlt_frame this )
 162 {
 163         return mlt_deque_pop_back( this->stack_image );
 164 }
 165
 166 /** Push a service.
 167 */
 168
 169 int mlt_frame_push_service( mlt_frame this, void *that )
 170 {
 171         return mlt_deque_push_back( this->stack_image, that );
 172 }
 173
 174 /** Pop a service.
 175 */
 176
 177 void *mlt_frame_pop_service( mlt_frame this )
 178 {
 179         return mlt_deque_pop_back( this->stack_image );
 180 }
 181
 182 /** Push an audio item on the stack.
 183 */
 184
 185 int mlt_frame_push_audio( mlt_frame this, void *that )
 186 {
 187         return mlt_deque_push_back( this->stack_audio, that );
 188 }
 189
 190 /** Pop an audio item from the stack
 191 */
 192
 193 void *mlt_frame_pop_audio( mlt_frame this )
 194 {
 195         return mlt_deque_pop_back( this->stack_audio );
 196 }
 197
 198 int mlt_frame_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
 199 {
 200         mlt_properties properties = mlt_frame_properties( this );
 201         mlt_get_image get_image = mlt_frame_pop_get_image( this );
 202         mlt_producer producer = mlt_properties_get_data( properties, "test_card_producer", NULL );
 203
 204         if ( get_image != NULL )
 205         {
 206                 return get_image( this, buffer, format, width, height, writable );
 207         }
 208         else if ( mlt_properties_get_data( properties, "image", NULL ) != NULL )
 209         {
 210                 *format = mlt_image_yuv422;
 211                 *buffer = mlt_properties_get_data( properties, "image", NULL );
 212                 *width = mlt_properties_get_int( properties, "width" );
 213                 *height = mlt_properties_get_int( properties, "height" );
 214         }
 215         else if ( producer != NULL )
 216         {
 217                 mlt_frame test_frame = NULL;
 218                 mlt_service_get_frame( mlt_producer_service( producer ), &test_frame, 0 );
 219                 if ( test_frame != NULL )
 220                 {
 221                         mlt_properties test_properties = mlt_frame_properties( test_frame );
 222                         mlt_properties_set_double( test_properties, "consumer_aspect_ratio", mlt_properties_get_double( properties, "consumer_aspect_ratio" ) );
 223                         mlt_properties_set( test_properties, "rescale.interp", mlt_properties_get( properties, "rescale.interp" ) );
 224                         mlt_frame_get_image( test_frame, buffer, format, width, height, writable );
 225                         mlt_properties_set_data( properties, "test_card_frame", test_frame, 0, ( mlt_destructor )mlt_frame_close, NULL );
 226                         mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
 227                         mlt_properties_set_int( properties, "width", *width );
 228                         mlt_properties_set_int( properties, "height", *height );
 229                         mlt_properties_set( properties, "rescale.interp", "none" );
 230                         mlt_properties_set( properties, "scale", "off" );
 231                 }
 232                 else
 233                 {
 234                         mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
 235                         mlt_frame_get_image( this, buffer, format, width, height, writable );
 236                 }
 237         }
 238         else
 239         {
 240                 register uint8_t *p;
 241                 register uint8_t *q;
 242                 int size = 0;
 243
 244                 *width = *width == 0 ? 720 : *width;
 245                 *height = *height == 0 ? 576 : *height;
 246                 size = *width * *height;
 247
 248                 mlt_properties_set_int( properties, "width", *width );
 249                 mlt_properties_set_int( properties, "height", *height );
 250                 mlt_properties_set_int( properties, "aspect_ratio", 1 );
 251
 252                 switch( *format )
 253                 {
 254                         case mlt_image_none:
 255                                 size = 0;
 256                                 *buffer = NULL;
 257                                 break;
 258                         case mlt_image_rgb24:
 259                                 size *= 3;
 260                                 size += *width * 3;
 261                                 *buffer = mlt_pool_alloc( size );
 262                                 if ( *buffer )
 263                                         memset( *buffer, 255, size );
 264                                 break;
 265                         case mlt_image_rgb24a:
 266                                 size *= 4;
 267                                 size += *width * 4;
 268                                 *buffer = mlt_pool_alloc( size );
 269                                 if ( *buffer )
 270                                         memset( *buffer, 255, size );
 271                                 break;
 272                         case mlt_image_yuv422:
 273                                 size *= 2;
 274                                 size += *width * 2;
 275                                 *buffer = mlt_pool_alloc( size );
 276                                 p = *buffer;
 277                                 q = p + size;
 278                                 while ( p != NULL && p != q )
 279                                 {
 280                                         *p ++ = 235;
 281                                         *p ++ = 128;
 282                                 }
 283                                 break;
 284                         case mlt_image_yuv420p:
 285                                 size = size * 3 / 2;
 286                                 *buffer = mlt_pool_alloc( size );
 287                                 if ( *buffer )
 288                                         memset( *buffer, 255, size );
 289                                 break;
 290                 }
 291
 292                 mlt_properties_set_data( properties, "image", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
 293                 mlt_properties_set_int( properties, "test_image", 1 );
 294         }
 295
 296         return 0;
 297 }
 298
 299 uint8_t *mlt_frame_get_alpha_mask( mlt_frame this )
 300 {
 301         if ( this->get_alpha_mask != NULL )
 302                 return this->get_alpha_mask( this );
 303         return NULL;
 304 }
 305
 306 int mlt_frame_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 307 {
 308         mlt_properties properties = mlt_frame_properties( this );
 309
 310         if ( this->get_audio != NULL )
 311         {
 312                 this->get_audio( this, buffer, format, frequency, channels, samples );
 313         }
 314         else if ( mlt_properties_get_data( properties, "audio", NULL ) )
 315         {
 316                 *buffer = mlt_properties_get_data( properties, "audio", NULL );
 317                 *frequency = mlt_properties_get_int( properties, "audio_frequency" );
 318                 *channels = mlt_properties_get_int( properties, "audio_channels" );
 319                 *samples = mlt_properties_get_int( properties, "audio_samples" );
 320         }
 321         else
 322         {
 323                 int size = 0;
 324                 *samples = *samples <= 0 ? 1920 : *samples;
 325                 *channels = *channels <= 0 ? 2 : *channels;
 326                 *frequency = *frequency <= 0 ? 48000 : *frequency;
 327                 size = *samples * *channels * sizeof( int16_t );
 328                 *buffer = mlt_pool_alloc( size );
 329                 if ( *buffer != NULL )
 330                         memset( *buffer, 0, size );
 331                 mlt_properties_set_data( properties, "audio", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
 332                 mlt_properties_set_int( properties, "test_audio", 1 );
 333         }
 334
 335         mlt_properties_set_int( properties, "audio_frequency", *frequency );
 336         mlt_properties_set_int( properties, "audio_channels", *channels );
 337         mlt_properties_set_int( properties, "audio_samples", *samples );
 338
 339         return 0;
 340 }
 341
 342 unsigned char *mlt_frame_get_waveform( mlt_frame this, double fps, int w, int h )
 343 {
 344         int16_t *pcm = NULL;
 345         mlt_properties properties = mlt_frame_properties( this );
 346         mlt_audio_format format = mlt_audio_pcm;
 347         int frequency = 32000; // lower frequency available?
 348         int channels = 2;
 349         int samples = mlt_sample_calculator( fps, frequency, mlt_frame_get_position( this ) );
 350
 351         // Get the pcm data
 352         mlt_frame_get_audio( this, &pcm, &format, &frequency, &channels, &samples );
 353
 354         // Make an 8-bit buffer large enough to hold rendering
 355         int size = w * h;
 356         unsigned char *bitmap = ( unsigned char* )mlt_pool_alloc( size );
 357         if ( bitmap != NULL )
 358                 memset( bitmap, 0, size );
 359         mlt_properties_set_data( properties, "waveform", bitmap, size, ( mlt_destructor )mlt_pool_release, NULL );
 360
 361         // Render vertical lines
 362         int16_t *ubound = pcm + samples * channels;
 363         int skip = samples / w - 1;
 364         int i, j, k;
 365
 366         // Iterate sample stream and along x coordinate
 367         for ( i = 0; i < w && pcm < ubound; i++ )
 368         {
 369                 // pcm data has channels interleaved
 370                 for ( j = 0; j < channels; j++ )
 371                 {
 372                         // Determine sample's magnitude from 2s complement;
 373                         int pcm_magnitude = *pcm < 0 ? ~(*pcm) + 1 : *pcm;
 374                         // The height of a line is the ratio of the magnitude multiplied by
 375                         // half the vertical resolution
 376                         int height = ( int )( ( double )( pcm_magnitude ) / 32768 * h / 2 );
 377                         // Determine the starting y coordinate - left channel above center,
 378                         // right channel below - currently assumes 2 channels
 379                         int displacement = ( h / 2 ) - ( 1 - j ) * height;
 380                         // Position buffer pointer using y coordinate, stride, and x coordinate
 381                         unsigned char *p = &bitmap[ i + displacement * w ];
 382
 383                         // Draw vertical line
 384                         for ( k = 0; k < height; k++ )
 385                                 p[ w * k ] = 0xFF;
 386
 387                         pcm++;
 388                 }
 389                 pcm += skip * channels;
 390         }
 391
 392         return bitmap;
 393 }
 394
 395
 396 void mlt_frame_close( mlt_frame this )
 397 {
 398         if ( this != NULL && mlt_properties_dec_ref( mlt_frame_properties( this ) ) <= 0 )
 399         {
 400                 mlt_deque_close( this->stack_image );
 401                 mlt_deque_close( this->stack_audio );
 402                 mlt_properties_close( &this->parent );
 403                 free( this );
 404         }
 405 }
 406
 407 /***** convenience functions *****/
 408
 409 int mlt_convert_rgb24a_to_yuv422( uint8_t *rgba, int width, int height, int stride, uint8_t *yuv, uint8_t *alpha )
 410 {
 411         int ret = 0;
 412         register int y0, y1, u0, u1, v0, v1;
 413         register int r, g, b;
 414         register uint8_t *d = yuv;
 415         register int i, j;
 416
 417         for ( i = 0; i < height; i++ )
 418         {
 419                 register uint8_t *s = rgba + ( stride * i );
 420                 for ( j = 0; j < ( width / 2 ); j++ )
 421                 {
 422                         r = *s++;
 423                         g = *s++;
 424                         b = *s++;
 425                         *alpha++ = *s++;
 426                         RGB2YUV (r, g, b, y0, u0 , v0);
 427                         r = *s++;
 428                         g = *s++;
 429                         b = *s++;
 430                         *alpha++ = *s++;
 431                         RGB2YUV (r, g, b, y1, u1 , v1);
 432                         *d++ = y0;
 433                         *d++ = (u0+u1) >> 1;
 434                         *d++ = y1;
 435                         *d++ = (v0+v1) >> 1;
 436                 }
 437                 if ( width % 2 )
 438                 {
 439                         r = *s++;
 440                         g = *s++;
 441                         b = *s++;
 442                         *alpha++ = *s++;
 443                         RGB2YUV (r, g, b, y0, u0 , v0);
 444                         *d++ = y0;
 445                         *d++ = u0;
 446                 }
 447         }
 448         return ret;
 449 }
 450
 451 int mlt_convert_rgb24_to_yuv422( uint8_t *rgb, int width, int height, int stride, uint8_t *yuv )
 452 {
 453         int ret = 0;
 454         register int y0, y1, u0, u1, v0, v1;
 455         register int r, g, b;
 456         register uint8_t *d = yuv;
 457         register int i, j;
 458
 459         for ( i = 0; i < height; i++ )
 460         {
 461                 register uint8_t *s = rgb + ( stride * i );
 462                 for ( j = 0; j < ( width / 2 ); j++ )
 463                 {
 464                         r = *s++;
 465                         g = *s++;
 466                         b = *s++;
 467                         RGB2YUV (r, g, b, y0, u0 , v0);
 468                         r = *s++;
 469                         g = *s++;
 470                         b = *s++;
 471                         RGB2YUV (r, g, b, y1, u1 , v1);
 472                         *d++ = y0;
 473                         *d++ = (u0+u1) >> 1;
 474                         *d++ = y1;
 475                         *d++ = (v0+v1) >> 1;
 476                 }
 477                 if ( width % 2 )
 478                 {
 479                         r = *s++;
 480                         g = *s++;
 481                         b = *s++;
 482                         RGB2YUV (r, g, b, y0, u0 , v0);
 483                         *d++ = y0;
 484                         *d++ = u0;
 485                 }
 486         }
 487         return ret;
 488 }
 489
 490 int mlt_convert_yuv420p_to_yuv422( uint8_t *yuv420p, int width, int height, int stride, uint8_t *yuv )
 491 {
 492         int ret = 0;
 493         register int i, j;
 494
 495         int half = width >> 1;
 496
 497         uint8_t *Y = yuv420p;
 498         uint8_t *U = Y + width * height;
 499         uint8_t *V = U + width * height / 4;
 500
 501         register uint8_t *d = yuv;
 502
 503         for ( i = 0; i < height; i++ )
 504         {
 505                 register uint8_t *u = U + ( i / 2 ) * ( half );
 506                 register uint8_t *v = V + ( i / 2 ) * ( half );
 507
 508                 for ( j = 0; j < half; j++ )
 509                 {
 510                         *d ++ = *Y ++;
 511                         *d ++ = *u ++;
 512                         *d ++ = *Y ++;
 513                         *d ++ = *v ++;
 514                 }
 515         }
 516         return ret;
 517 }
 518
 519 void mlt_resize_yuv422( uint8_t *output, int owidth, int oheight, uint8_t *input, int iwidth, int iheight )
 520 {
 521         // Calculate strides
 522         int istride = iwidth * 2;
 523         int ostride = owidth * 2;
 524
 525         iwidth = iwidth - ( iwidth % 4 );
 526         owidth = owidth - ( owidth % 4 );
 527         iheight = iheight - ( iheight % 2 );
 528         oheight = oheight - ( oheight % 2 );
 529
 530         // Optimisation point
 531         if ( iwidth == owidth && iheight == oheight )
 532                 memcpy( output, input, iheight * istride );
 533
 534         // Coordinates (0,0 is middle of output)
 535         int y;
 536
 537         // Calculate ranges
 538         int out_x_range = owidth / 2;
 539         int out_y_range = oheight / 2;
 540         int in_x_range = iwidth / 2 < out_x_range ? iwidth / 2 : out_x_range;
 541         int in_y_range = iheight / 2 < out_y_range ? iheight / 2 : out_y_range;
 542
 543         // Output pointers
 544         uint8_t *out_line = output;
 545         uint8_t *out_ptr = out_line;
 546
 547         // Calculate a middle and possibly invalid pointer in the input
 548         uint8_t *in_middle = input + istride * ( iheight / 2 ) + ( iwidth / 2 ) * 2;
 549         int in_line = - in_y_range * istride - in_x_range * 2;
 550
 551         int elements;
 552
 553         // Fill whole section with black
 554         y = out_y_range - ( iheight / 2 );
 555         int blank_elements = ostride * y / 2;
 556         elements = blank_elements;
 557         while ( elements -- )
 558         {
 559                 *out_line ++ = 16;
 560                 *out_line ++ = 128;
 561         }
 562
 563         int active_width = 2 * iwidth;
 564         int inactive_width = out_x_range - in_x_range;
 565         uint8_t *p = NULL;
 566         uint8_t *end = NULL;
 567
 568         // Loop for the entirety of our output height.
 569         while ( iheight -- )
 570         {
 571         // Start at the beginning of the line
 572         out_ptr = out_line;
 573
 574                 // Fill the outer part with black
 575                 elements = inactive_width;
 576                 while ( elements -- )
 577                 {
 578                         *out_ptr ++ = 16;
 579                         *out_ptr ++ = 128;
 580                 }
 581
 582                 // We're in the input range for this row.
 583                 p = in_middle + in_line;
 584                 end = out_ptr + active_width;
 585                 while ( out_ptr != end )
 586                 {
 587                         *out_ptr ++ = *p ++;
 588                         *out_ptr ++ = *p ++;
 589                 }
 590
 591                 // Fill the outer part with black
 592                 elements = inactive_width;
 593                 while ( elements -- )
 594                 {
 595                         *out_ptr ++ = 16;
 596                         *out_ptr ++ = 128;
 597                 }
 598
 599                 // Move to next input line
 600                 in_line += istride;
 601
 602         // Move to next output line
 603         out_line += ostride;
 604         }
 605
 606         // Fill whole section with black
 607         elements = blank_elements;
 608         while ( elements -- )
 609         {
 610                 *out_line ++ = 16;
 611                 *out_line ++ = 128;
 612         }
 613 }
 614
 615 /** A resizing function for yuv422 frames - this does not rescale, but simply
 616         resizes. It assumes yuv422 images available on the frame so use with care.
 617 */
 618
 619 uint8_t *mlt_frame_resize_yuv422( mlt_frame this, int owidth, int oheight )
 620 {
 621         // Get properties
 622         mlt_properties properties = mlt_frame_properties( this );
 623
 624         // Get the input image, width and height
 625         uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
 626         int iwidth = mlt_properties_get_int( properties, "width" );
 627         int iheight = mlt_properties_get_int( properties, "height" );
 628
 629         // If width and height are correct, don't do anything
 630         if ( iwidth != owidth || iheight != oheight )
 631         {
 632                 // Create the output image
 633                 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * 2 );
 634
 635                 // Call the generic resize
 636                 mlt_resize_yuv422( output, owidth, oheight, input, iwidth, iheight );
 637
 638                 // Now update the frame
 639                 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 640                 mlt_properties_set_int( properties, "width", owidth );
 641                 mlt_properties_set_int( properties, "height", oheight );
 642
 643                 // Return the output
 644                 return output;
 645         }
 646         // No change, return input
 647         return input;
 648 }
 649
 650 /** A rescaling function for yuv422 frames - low quality, and provided for testing
 651         only. It assumes yuv422 images available on the frame so use with care.
 652 */
 653
 654 uint8_t *mlt_frame_rescale_yuv422( mlt_frame this, int owidth, int oheight )
 655 {
 656         // Get properties
 657         mlt_properties properties = mlt_frame_properties( this );
 658
 659         // Get the input image, width and height
 660         uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
 661         int iwidth = mlt_properties_get_int( properties, "width" );
 662         int iheight = mlt_properties_get_int( properties, "height" );
 663
 664         // If width and height are correct, don't do anything
 665         if ( iwidth != owidth || iheight != oheight )
 666         {
 667                 // Create the output image
 668                 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * 2 );
 669
 670                 // Calculate strides
 671                 int istride = iwidth * 2;
 672                 int ostride = owidth * 2;
 673
 674                 iwidth = iwidth - ( iwidth % 4 );
 675
 676                 // Derived coordinates
 677                 int dy, dx;
 678
 679         // Calculate ranges
 680         int out_x_range = owidth / 2;
 681         int out_y_range = oheight / 2;
 682         int in_x_range = iwidth / 2;
 683         int in_y_range = iheight / 2;
 684
 685         // Output pointers
 686         register uint8_t *out_line = output;
 687         register uint8_t *out_ptr;
 688
 689         // Calculate a middle pointer
 690         uint8_t *in_middle = input + istride * in_y_range + in_x_range * 2;
 691         uint8_t *in_line;
 692
 693                 // Generate the affine transform scaling values
 694                 register int scale_width = ( iwidth << 16 ) / owidth;
 695                 register int scale_height = ( iheight << 16 ) / oheight;
 696                 register int base = 0;
 697
 698                 int outer = out_x_range * scale_width;
 699                 int bottom = out_y_range * scale_height;
 700
 701         // Loop for the entirety of our output height.
 702         for ( dy = - bottom; dy < bottom; dy += scale_height )
 703         {
 704                 // Start at the beginning of the line
 705                 out_ptr = out_line;
 706
 707                 // Pointer to the middle of the input line
 708                 in_line = in_middle + ( dy >> 16 ) * istride;
 709
 710                 // Loop for the entirety of our output row.
 711                 for ( dx = - outer; dx < outer; dx += scale_width )
 712                 {
 713                                 base = dx >> 15;
 714                                 base &= 0xfffffffe;
 715                                 *out_ptr ++ = *( in_line + base );
 716                                 base &= 0xfffffffc;
 717                                 *out_ptr ++ = *( in_line + base + 1 );
 718                                 dx += scale_width;
 719                                 base = dx >> 15;
 720                                 base &= 0xfffffffe;
 721                                 *out_ptr ++ = *( in_line + base );
 722                                 base &= 0xfffffffc;
 723                                 *out_ptr ++ = *( in_line + base + 3 );
 724                 }
 725
 726                 // Move to next output line
 727                 out_line += ostride;
 728         }
 729
 730                 // Now update the frame
 731                 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
 732                 mlt_properties_set_int( properties, "width", owidth );
 733                 mlt_properties_set_int( properties, "height", oheight );
 734
 735                 // Return the output
 736                 return output;
 737         }
 738
 739         // No change, return input
 740         return input;
 741 }
 742
 743 int mlt_frame_mix_audio( mlt_frame this, mlt_frame that, float weight_start, float weight_end, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
 744 {
 745         int ret = 0;
 746         int16_t *src, *dest;
 747         int frequency_src = *frequency, frequency_dest = *frequency;
 748         int channels_src = *channels, channels_dest = *channels;
 749         int samples_src = *samples, samples_dest = *samples;
 750         int i, j;
 751         double d = 0, s = 0;
 752
 753         mlt_frame_get_audio( this, &dest, format, &frequency_dest, &channels_dest, &samples_dest );
 754         //fprintf( stderr, "mix: frame dest samples %d channels %d position %lld\n", samples_dest, channels_dest, mlt_properties_get_position( mlt_frame_properties( this ), "_position" ) );
 755         mlt_frame_get_audio( that, &src, format, &frequency_src, &channels_src, &samples_src );
 756         //fprintf( stderr, "mix: frame src  samples %d channels %d\n", samples_src, channels_src );
 757
 758         if ( channels_src > 6 )
 759                 channels_src = 0;
 760         if ( channels_dest > 6 )
 761                 channels_dest = 0;
 762         if ( samples_src > 4000 )
 763                 samples_src = 0;
 764         if ( samples_dest > 4000 )
 765                 samples_dest = 0;
 766
 767         // determine number of samples to process
 768         *samples = samples_src < samples_dest ? samples_src : samples_dest;
 769         *channels = channels_src < channels_dest ? channels_src : channels_dest;
 770         *buffer = dest;
 771         *frequency = frequency_dest;
 772
 773         // Compute a smooth ramp over start to end
 774         float weight = weight_start;
 775         float weight_step = ( weight_end - weight_start ) / *samples;
 776
 777         // Mixdown
 778         for ( i = 0; i < *samples; i++ )
 779         {
 780                 for ( j = 0; j < *channels; j++ )
 781                 {
 782                         if ( j < channels_dest )
 783                                 d = (double) dest[ i * channels_dest + j ];
 784                         if ( j < channels_src )
 785                                 s = (double) src[ i * channels_src + j ];
 786                         dest[ i * channels_dest + j ] = s * weight + d * ( 1.0 - weight );
 787                 }
 788                 weight += weight_step;
 789         }
 790
 791         return ret;
 792 }
 793
 794 int mlt_sample_calculator( float fps, int frequency, int64_t position )
 795 {
 796         int samples = 0;
 797
 798         if ( ( int )( fps * 100 ) == 2997 )
 799         {
 800                 samples = frequency / 30;
 801
 802                 switch ( frequency )
 803                 {
 804                         case 48000:
 805                                 if ( position % 5 != 0 )
 806                                         samples += 2;
 807                                 break;
 808                         case 44100:
 809                                 if ( position % 300 == 0 )
 810                                         samples = 1471;
 811                                 else if ( position % 30 == 0 )
 812                                         samples = 1470;
 813                                 else if ( position % 2 == 0 )
 814                                         samples = 1472;
 815                                 else
 816                                         samples = 1471;
 817                                 break;
 818                         case 32000:
 819                                 if ( position % 30 == 0 )
 820                                         samples = 1068;
 821                                 else if ( position % 29 == 0 )
 822                                         samples = 1067;
 823                                 else if ( position % 4 == 2 )
 824                                         samples = 1067;
 825                                 else
 826                                         samples = 1068;
 827                                 break;
 828                         default:
 829                                 samples = 0;
 830                 }
 831         }
 832         else if ( fps != 0 )
 833         {
 834                 samples = frequency / fps;
 835         }
 836
 837         return samples;
 838 }