producer_colour
[melted] / 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 }
57 else
58 {
59 mlt_properties_set_int( properties, "width", 720 );
60 mlt_properties_set_int( properties, "height", 480 );
61 mlt_properties_set_int( properties, "normalised_width", 720 );
62 mlt_properties_set_int( properties, "normalised_height", 480 );
63 }
64
65 mlt_properties_set_double( properties, "aspect_ratio", 4.0 / 3.0 );
66 mlt_properties_set_data( properties, "audio", NULL, 0, NULL, NULL );
67 mlt_properties_set_data( properties, "alpha", NULL, 0, NULL, NULL );
68
69 // Construct stacks for frames and methods
70 this->stack_get_image = mlt_deque_init( );
71 this->stack_frame = mlt_deque_init( );
72 this->stack_service = 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->parent;
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_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_get_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_get_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_frame, 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_frame );
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_service, 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_service );
180 }
181
182 int mlt_frame_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
183 {
184 mlt_properties properties = mlt_frame_properties( this );
185 mlt_get_image get_image = mlt_frame_pop_get_image( this );
186 mlt_producer producer = mlt_properties_get_data( properties, "test_card_producer", NULL );
187
188 if ( get_image != NULL )
189 {
190 return get_image( this, buffer, format, width, height, writable );
191 }
192 else if ( mlt_properties_get_data( properties, "image", NULL ) != NULL )
193 {
194 *format = mlt_image_yuv422;
195 *buffer = mlt_properties_get_data( properties, "image", NULL );
196 *width = mlt_properties_get_int( properties, "width" );
197 *height = mlt_properties_get_int( properties, "height" );
198 }
199 else if ( producer != NULL )
200 {
201 mlt_frame test_frame = NULL;
202 mlt_service_get_frame( mlt_producer_service( producer ), &test_frame, 0 );
203 if ( test_frame != NULL )
204 {
205 mlt_properties test_properties = mlt_frame_properties( test_frame );
206 mlt_properties_set_double( test_properties, "consumer_aspect_ratio", mlt_properties_get_double( properties, "consumer_aspect_ratio" ) );
207 mlt_properties_set_double( test_properties, "consumer_scale", mlt_properties_get_double( properties, "consumer_scale" ) );
208 mlt_properties_set( test_properties, "rescale.interp", "nearest" );
209 mlt_frame_get_image( test_frame, buffer, format, width, height, writable );
210 mlt_properties_set_data( properties, "test_card_frame", test_frame, 0, ( mlt_destructor )mlt_frame_close, NULL );
211 mlt_properties_set_data( properties, "image", *buffer, *width * *height * 2, NULL, NULL );
212 mlt_properties_set_int( properties, "width", *width );
213 mlt_properties_set_int( properties, "height", *height );
214 }
215 else
216 {
217 mlt_properties_set_data( properties, "test_card_producer", NULL, 0, NULL, NULL );
218 mlt_frame_get_image( this, buffer, format, width, height, writable );
219 }
220 }
221 else
222 {
223 uint8_t *p;
224 uint8_t *q;
225 int size = 0;
226
227 *width = *width == 0 ? 720 : *width;
228 *height = *height == 0 ? 576 : *height;
229 size = *width * *height;
230
231 mlt_properties_set_int( properties, "width", *width );
232 mlt_properties_set_int( properties, "height", *height );
233
234 switch( *format )
235 {
236 case mlt_image_none:
237 size = 0;
238 *buffer = NULL;
239 break;
240 case mlt_image_rgb24:
241 size *= 3;
242 size += *width * 3;
243 *buffer = mlt_pool_alloc( size );
244 if ( *buffer )
245 memset( *buffer, 255, size );
246 break;
247 case mlt_image_rgb24a:
248 size *= 4;
249 size += *width * 4;
250 *buffer = mlt_pool_alloc( size );
251 if ( *buffer )
252 memset( *buffer, 255, size );
253 break;
254 case mlt_image_yuv422:
255 size *= 2;
256 size += *width * 2;
257 *buffer = mlt_pool_alloc( size );
258 p = *buffer;
259 q = p + size;
260 while ( p != NULL && p != q )
261 {
262 *p ++ = 235;
263 *p ++ = 128;
264 }
265 break;
266 case mlt_image_yuv420p:
267 size = size * 3 / 2;
268 *buffer = mlt_pool_alloc( size );
269 if ( *buffer )
270 memset( *buffer, 255, size );
271 break;
272 }
273
274 mlt_properties_set_data( properties, "image", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
275 mlt_properties_set_int( properties, "test_image", 1 );
276 }
277
278 return 0;
279 }
280
281 uint8_t *mlt_frame_get_alpha_mask( mlt_frame this )
282 {
283 if ( this->get_alpha_mask != NULL )
284 return this->get_alpha_mask( this );
285 return NULL;
286 }
287
288 int mlt_frame_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
289 {
290 mlt_properties properties = mlt_frame_properties( this );
291
292 if ( this->get_audio != NULL )
293 {
294 return this->get_audio( this, buffer, format, frequency, channels, samples );
295 }
296 else
297 {
298 int size = 0;
299 *samples = *samples <= 0 ? 1920 : *samples;
300 *channels = *channels <= 0 ? 2 : *channels;
301 *frequency = *frequency <= 0 ? 48000 : *frequency;
302 size = *samples * *channels * sizeof( int16_t );
303 *buffer = mlt_pool_alloc( size );
304 if ( *buffer != NULL )
305 memset( *buffer, 0, size );
306 mlt_properties_set_data( properties, "audio", *buffer, size, ( mlt_destructor )mlt_pool_release, NULL );
307 mlt_properties_set_int( properties, "test_audio", 1 );
308 }
309 return 0;
310 }
311
312 void mlt_frame_close( mlt_frame this )
313 {
314 if ( this != NULL )
315 {
316 mlt_deque_close( this->stack_get_image );
317 mlt_deque_close( this->stack_frame );
318 mlt_deque_close( this->stack_service );
319 mlt_properties_close( &this->parent );
320 free( this );
321 }
322 }
323
324 /***** convenience functions *****/
325
326 int mlt_convert_rgb24a_to_yuv422( uint8_t *rgba, int width, int height, int stride, uint8_t *yuv, uint8_t *alpha )
327 {
328 int ret = 0;
329 register int y0, y1, u0, u1, v0, v1;
330 register int r, g, b;
331 register uint8_t *d = yuv;
332 register int i, j;
333
334 for ( i = 0; i < height; i++ )
335 {
336 register uint8_t *s = rgba + ( stride * i );
337 for ( j = 0; j < ( width / 2 ); j++ )
338 {
339 r = *s++;
340 g = *s++;
341 b = *s++;
342 *alpha++ = *s++;
343 RGB2YUV (r, g, b, y0, u0 , v0);
344 r = *s++;
345 g = *s++;
346 b = *s++;
347 *alpha++ = *s++;
348 RGB2YUV (r, g, b, y1, u1 , v1);
349 *d++ = y0;
350 *d++ = (u0+u1) >> 1;
351 *d++ = y1;
352 *d++ = (v0+v1) >> 1;
353 }
354 if ( width % 2 )
355 {
356 r = *s++;
357 g = *s++;
358 b = *s++;
359 *alpha++ = *s++;
360 RGB2YUV (r, g, b, y0, u0 , v0);
361 *d++ = y0;
362 *d++ = u0;
363 }
364 }
365 return ret;
366 }
367
368 int mlt_convert_rgb24_to_yuv422( uint8_t *rgb, int width, int height, int stride, uint8_t *yuv )
369 {
370 int ret = 0;
371 register int y0, y1, u0, u1, v0, v1;
372 register int r, g, b;
373 register uint8_t *d = yuv;
374 register int i, j;
375
376 for ( i = 0; i < height; i++ )
377 {
378 register uint8_t *s = rgb + ( stride * i );
379 for ( j = 0; j < ( width / 2 ); j++ )
380 {
381 r = *s++;
382 g = *s++;
383 b = *s++;
384 RGB2YUV (r, g, b, y0, u0 , v0);
385 r = *s++;
386 g = *s++;
387 b = *s++;
388 RGB2YUV (r, g, b, y1, u1 , v1);
389 *d++ = y0;
390 *d++ = (u0+u1) >> 1;
391 *d++ = y1;
392 *d++ = (v0+v1) >> 1;
393 }
394 if ( width % 2 )
395 {
396 r = *s++;
397 g = *s++;
398 b = *s++;
399 RGB2YUV (r, g, b, y0, u0 , v0);
400 *d++ = y0;
401 *d++ = u0;
402 }
403 }
404 return ret;
405 }
406
407 int mlt_convert_yuv420p_to_yuv422( uint8_t *yuv420p, int width, int height, int stride, uint8_t *yuv )
408 {
409 int ret = 0;
410 register int i, j;
411
412 int half = width >> 1;
413
414 uint8_t *Y = yuv420p;
415 uint8_t *U = Y + width * height;
416 uint8_t *V = U + width * height / 4;
417
418 register uint8_t *d = yuv;
419
420 for ( i = 0; i < height; i++ )
421 {
422 register uint8_t *u = U + ( i / 2 ) * ( half );
423 register uint8_t *v = V + ( i / 2 ) * ( half );
424
425 for ( j = 0; j < half; j++ )
426 {
427 *d ++ = *Y ++;
428 *d ++ = *u ++;
429 *d ++ = *Y ++;
430 *d ++ = *v ++;
431 }
432 }
433 return ret;
434 }
435
436 void mlt_resize_yuv422( uint8_t *output, int owidth, int oheight, uint8_t *input, int iwidth, int iheight )
437 {
438 // Calculate strides
439 int istride = iwidth * 2;
440 int ostride = owidth * 2;
441
442 iwidth = iwidth - ( iwidth % 4 );
443 owidth = owidth - ( owidth % 4 );
444 iheight = iheight - ( iheight % 2 );
445 oheight = oheight - ( oheight % 2 );
446
447 // Optimisation point
448 if ( iwidth == owidth && iheight == oheight )
449 memcpy( output, input, iheight * istride );
450
451 // Coordinates (0,0 is middle of output)
452 int y;
453
454 // Calculate ranges
455 int out_x_range = owidth / 2;
456 int out_y_range = oheight / 2;
457 int in_x_range = iwidth / 2 < out_x_range ? iwidth / 2 : out_x_range;
458 int in_y_range = iheight / 2 < out_y_range ? iheight / 2 : out_y_range;
459
460 // Output pointers
461 uint8_t *out_line = output;
462 uint8_t *out_ptr = out_line;
463
464 // Calculate a middle and possibly invalid pointer in the input
465 uint8_t *in_middle = input + istride * ( iheight / 2 ) + ( iwidth / 2 ) * 2;
466 int in_line = - in_y_range * istride - in_x_range * 2;
467
468 int elements;
469
470 // Fill whole section with black
471 y = out_y_range - ( iheight / 2 );
472 int blank_elements = ostride * y / 2;
473 elements = blank_elements;
474 while ( elements -- )
475 {
476 *out_line ++ = 16;
477 *out_line ++ = 128;
478 }
479
480 int active_width = 2 * iwidth;
481 int inactive_width = out_x_range - in_x_range;
482
483 // Loop for the entirety of our output height.
484 while ( iheight -- )
485 {
486 // Start at the beginning of the line
487 out_ptr = out_line;
488
489 // Fill the outer part with black
490 elements = inactive_width;
491 while ( elements -- )
492 {
493 *out_ptr ++ = 16;
494 *out_ptr ++ = 128;
495 }
496
497 // We're in the input range for this row.
498 memcpy( out_ptr, in_middle + in_line, active_width );
499 out_ptr += active_width;
500
501 // Fill the outer part with black
502 elements = inactive_width;
503 while ( elements -- )
504 {
505 *out_ptr ++ = 16;
506 *out_ptr ++ = 128;
507 }
508
509 // Move to next input line
510 in_line += istride;
511
512 // Move to next output line
513 out_line += ostride;
514 }
515
516 // Fill whole section with black
517 elements = blank_elements;
518 while ( elements -- )
519 {
520 *out_line ++ = 16;
521 *out_line ++ = 128;
522 }
523 }
524
525 /** A resizing function for yuv422 frames - this does not rescale, but simply
526 resizes. It assumes yuv422 images available on the frame so use with care.
527 */
528
529 uint8_t *mlt_frame_resize_yuv422( mlt_frame this, int owidth, int oheight )
530 {
531 // Get properties
532 mlt_properties properties = mlt_frame_properties( this );
533
534 // Get the input image, width and height
535 uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
536 int iwidth = mlt_properties_get_int( properties, "width" );
537 int iheight = mlt_properties_get_int( properties, "height" );
538
539 // If width and height are correct, don't do anything
540 if ( iwidth != owidth || iheight != oheight )
541 {
542 // Create the output image
543 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * 2 );
544
545 // Call the generic resize
546 mlt_resize_yuv422( output, owidth, oheight, input, iwidth, iheight );
547
548 // Now update the frame
549 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
550 mlt_properties_set_int( properties, "width", owidth );
551 mlt_properties_set_int( properties, "height", oheight );
552
553 // Return the output
554 return output;
555 }
556 // No change, return input
557 return input;
558 }
559
560 /** A rescaling function for yuv422 frames - low quality, and provided for testing
561 only. It assumes yuv422 images available on the frame so use with care.
562 */
563
564 uint8_t *mlt_frame_rescale_yuv422( mlt_frame this, int owidth, int oheight )
565 {
566 // Get properties
567 mlt_properties properties = mlt_frame_properties( this );
568
569 // Get the input image, width and height
570 uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
571 int iwidth = mlt_properties_get_int( properties, "width" );
572 int iheight = mlt_properties_get_int( properties, "height" );
573
574 // If width and height are correct, don't do anything
575 if ( iwidth != owidth || iheight != oheight )
576 {
577 // Create the output image
578 uint8_t *output = mlt_pool_alloc( owidth * ( oheight + 1 ) * 2 );
579
580 // Calculate strides
581 int istride = iwidth * 2;
582 int ostride = owidth * 2;
583
584 iwidth = iwidth - ( iwidth % 4 );
585
586 // Derived coordinates
587 int dy, dx;
588
589 // Calculate ranges
590 int out_x_range = owidth / 2;
591 int out_y_range = oheight / 2;
592 int in_x_range = iwidth / 2;
593 int in_y_range = iheight / 2;
594
595 // Output pointers
596 register uint8_t *out_line = output;
597 register uint8_t *out_ptr;
598
599 // Calculate a middle pointer
600 uint8_t *in_middle = input + istride * in_y_range + in_x_range * 2;
601 uint8_t *in_line;
602
603 // Generate the affine transform scaling values
604 register int scale_width = ( iwidth << 16 ) / owidth;
605 register int scale_height = ( iheight << 16 ) / oheight;
606 register int base = 0;
607
608 int outer = out_x_range * scale_width;
609 int bottom = out_y_range * scale_height;
610
611 // Loop for the entirety of our output height.
612 for ( dy = - bottom; dy < bottom; dy += scale_height )
613 {
614 // Start at the beginning of the line
615 out_ptr = out_line;
616
617 // Pointer to the middle of the input line
618 in_line = in_middle + ( dy >> 16 ) * istride;
619
620 // Loop for the entirety of our output row.
621 for ( dx = - outer; dx < outer; dx += scale_width )
622 {
623 base = dx >> 15;
624 base &= 0xfffffffe;
625 *out_ptr ++ = *( in_line + base );
626 base &= 0xfffffffc;
627 *out_ptr ++ = *( in_line + base + 1 );
628 dx += scale_width;
629 base = dx >> 15;
630 base &= 0xfffffffe;
631 *out_ptr ++ = *( in_line + base );
632 base &= 0xfffffffc;
633 *out_ptr ++ = *( in_line + base + 3 );
634 }
635
636 // Move to next output line
637 out_line += ostride;
638 }
639
640 // Now update the frame
641 mlt_properties_set_data( properties, "image", output, owidth * ( oheight + 1 ) * 2, ( mlt_destructor )mlt_pool_release, NULL );
642 mlt_properties_set_int( properties, "width", owidth );
643 mlt_properties_set_int( properties, "height", oheight );
644
645 // Return the output
646 return output;
647 }
648
649 // No change, return input
650 return input;
651 }
652
653 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 )
654 {
655 int ret = 0;
656 int16_t *src, *dest;
657 int frequency_src = *frequency, frequency_dest = *frequency;
658 int channels_src = *channels, channels_dest = *channels;
659 int samples_src = *samples, samples_dest = *samples;
660 int i, j;
661 double d = 0, s = 0;
662
663 mlt_frame_get_audio( this, &dest, format, &frequency_dest, &channels_dest, &samples_dest );
664 //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" ) );
665 mlt_frame_get_audio( that, &src, format, &frequency_src, &channels_src, &samples_src );
666 //fprintf( stderr, "mix: frame src samples %d channels %d\n", samples_src, channels_src );
667
668 if ( channels_src > 6 )
669 channels_src = 0;
670 if ( channels_dest > 6 )
671 channels_dest = 0;
672 if ( samples_src > 4000 )
673 samples_src = 0;
674 if ( samples_dest > 4000 )
675 samples_dest = 0;
676
677 // determine number of samples to process
678 *samples = samples_src < samples_dest ? samples_src : samples_dest;
679 *channels = channels_src < channels_dest ? channels_src : channels_dest;
680 *buffer = dest;
681 *frequency = frequency_dest;
682
683 // Compute a smooth ramp over start to end
684 float weight = weight_start;
685 float weight_step = ( weight_end - weight_start ) / *samples;
686
687 // Mixdown
688 for ( i = 0; i < *samples; i++ )
689 {
690 for ( j = 0; j < *channels; j++ )
691 {
692 if ( j < channels_dest )
693 d = (double) dest[ i * channels_dest + j ];
694 if ( j < channels_src )
695 s = (double) src[ i * channels_src + j ];
696 dest[ i * channels_dest + j ] = s * weight + d * ( 1.0 - weight );
697 }
698 weight += weight_step;
699 }
700
701 return ret;
702 }
703
704 int mlt_sample_calculator( float fps, int frequency, int64_t position )
705 {
706 int samples = 0;
707
708 if ( fps > 29 && fps <= 30 )
709 {
710 samples = frequency / 30;
711
712 switch ( frequency )
713 {
714 case 48000:
715 if ( position % 5 != 0 )
716 samples += 2;
717 break;
718 case 44100:
719 if ( position % 300 == 0 )
720 samples = 1471;
721 else if ( position % 30 == 0 )
722 samples = 1470;
723 else if ( position % 2 == 0 )
724 samples = 1472;
725 else
726 samples = 1471;
727 break;
728 case 32000:
729 if ( position % 30 == 0 )
730 samples = 1068;
731 else if ( position % 29 == 0 )
732 samples = 1067;
733 else if ( position % 4 == 2 )
734 samples = 1067;
735 else
736 samples = 1068;
737 break;
738 default:
739 samples = 0;
740 }
741 }
742 else if ( fps != 0 )
743 {
744 samples = frequency / fps;
745 }
746
747 return samples;
748 }
749