Minor mods
[melted] / mlt / 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 <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26
27 typedef struct
28 {
29 mlt_image_format vfmt;
30 int width;
31 int height;
32 uint8_t *image;
33 uint8_t *alpha;
34 mlt_audio_format afmt;
35 int16_t *audio;
36 }
37 frame_test;
38
39 static frame_test test_card = { mlt_image_none, 0, 0, NULL, NULL, mlt_audio_none, NULL };
40
41 /** Constructor for a frame.
42 */
43
44 mlt_frame mlt_frame_init( )
45 {
46 // Allocate a frame
47 mlt_frame this = calloc( sizeof( struct mlt_frame_s ), 1 );
48
49 if ( this != NULL )
50 {
51 // Initialise the properties
52 mlt_properties properties = &this->parent;
53 mlt_properties_init( properties, this );
54
55 // Set default properties on the frame
56 mlt_properties_set_position( properties, "position", 0.0 );
57 mlt_properties_set_data( properties, "image", NULL, 0, NULL, NULL );
58 mlt_properties_set_int( properties, "width", 720 );
59 mlt_properties_set_int( properties, "height", 576 );
60 mlt_properties_set_double( properties, "aspect_ratio", 4.0 / 3.0 );
61 mlt_properties_set_data( properties, "audio", NULL, 0, NULL, NULL );
62 mlt_properties_set_data( properties, "alpha", NULL, 0, NULL, NULL );
63 }
64 return this;
65 }
66
67 /** Fetch the frames properties.
68 */
69
70 mlt_properties mlt_frame_properties( mlt_frame this )
71 {
72 return &this->parent;
73 }
74
75 /** Check if we have a way to derive something other than a test card.
76 */
77
78 int mlt_frame_is_test_card( mlt_frame this )
79 {
80 return this->stack_get_image_size == 0;
81 }
82
83 /** Get the aspect ratio of the frame.
84 */
85
86 double mlt_frame_get_aspect_ratio( mlt_frame this )
87 {
88 mlt_properties properties = mlt_frame_properties( this );
89 return mlt_properties_get_double( properties, "aspect_ratio" );
90 }
91
92 /** Set the aspect ratio of the frame.
93 */
94
95 int mlt_frame_set_aspect_ratio( mlt_frame this, double value )
96 {
97 mlt_properties properties = mlt_frame_properties( this );
98 return mlt_properties_set_double( properties, "aspect_ratio", value );
99 }
100
101 /** Get the position of this frame.
102 */
103
104 mlt_position mlt_frame_get_position( mlt_frame this )
105 {
106 mlt_properties properties = mlt_frame_properties( this );
107 return mlt_properties_get_position( properties, "position" );
108 }
109
110 /** Set the position of this frame.
111 */
112
113 int mlt_frame_set_position( mlt_frame this, mlt_position value )
114 {
115 mlt_properties properties = mlt_frame_properties( this );
116 return mlt_properties_set_position( properties, "position", value );
117 }
118
119 /** Stack a get_image callback.
120 */
121
122 int mlt_frame_push_get_image( mlt_frame this, mlt_get_image get_image )
123 {
124 int ret = this->stack_get_image_size >= 10;
125 if ( ret == 0 )
126 this->stack_get_image[ this->stack_get_image_size ++ ] = get_image;
127 return ret;
128 }
129
130 /** Pop a get_image callback.
131 */
132
133 mlt_get_image mlt_frame_pop_get_image( mlt_frame this )
134 {
135 mlt_get_image result = NULL;
136 if ( this->stack_get_image_size > 0 )
137 result = this->stack_get_image[ -- this->stack_get_image_size ];
138 return result;
139 }
140
141 /** Push a frame.
142 */
143
144 int mlt_frame_push_frame( mlt_frame this, mlt_frame that )
145 {
146 int ret = this->stack_frame_size >= 10;
147 if ( ret == 0 )
148 this->stack_frame[ this->stack_frame_size ++ ] = that;
149 return ret;
150 }
151
152 /** Pop a frame.
153 */
154
155 mlt_frame mlt_frame_pop_frame( mlt_frame this )
156 {
157 mlt_frame result = NULL;
158 if ( this->stack_frame_size > 0 )
159 result = this->stack_frame[ -- this->stack_frame_size ];
160 return result;
161 }
162
163 int mlt_frame_get_image( mlt_frame this, uint8_t **buffer, mlt_image_format *format, int *width, int *height, int writable )
164 {
165 mlt_properties properties = mlt_frame_properties( this );
166 mlt_get_image get_image = mlt_frame_pop_get_image( this );
167
168 if ( get_image != NULL )
169 {
170 return get_image( this, buffer, format, width, height, writable );
171 }
172 else if ( mlt_properties_get_data( properties, "image", NULL ) != NULL )
173 {
174 *format = mlt_image_yuv422;
175 *buffer = mlt_properties_get_data( properties, "image", NULL );
176 *width = mlt_properties_get_int( properties, "width" );
177 *height = mlt_properties_get_int( properties, "height" );
178 }
179 else
180 {
181 if ( test_card.vfmt != *format )
182 {
183 uint8_t *p;
184 uint8_t *q;
185
186 test_card.vfmt = *format;
187 test_card.width = *width == 0 ? 720 : *width;
188 test_card.height = *height == 0 ? 576 : *height;
189
190 switch( *format )
191 {
192 case mlt_image_none:
193 break;
194 case mlt_image_rgb24:
195 test_card.image = realloc( test_card.image, test_card.width * test_card.height * 3 );
196 memset( test_card.image, 255, test_card.width * test_card.height * 3 );
197 break;
198 case mlt_image_rgb24a:
199 test_card.image = realloc( test_card.image, test_card.width * test_card.height * 4 );
200 memset( test_card.image, 255, test_card.width * test_card.height * 4 );
201 break;
202 case mlt_image_yuv422:
203 test_card.image = realloc( test_card.image, test_card.width * test_card.height * 2 );
204 p = test_card.image;
205 q = test_card.image + test_card.width * test_card.height * 2;
206 while ( p != q )
207 {
208 *p ++ = 255;
209 *p ++ = 128;
210 }
211 break;
212 case mlt_image_yuv420p:
213 test_card.image = realloc( test_card.image, test_card.width * test_card.height * 3 / 2 );
214 memset( test_card.image, 255, test_card.width * test_card.height * 3 / 2 );
215 break;
216 }
217 }
218
219 *width = test_card.width;
220 *height = test_card.height;
221 *buffer = test_card.image;
222 }
223
224 return 0;
225 }
226
227 uint8_t *mlt_frame_get_alpha_mask( mlt_frame this )
228 {
229 if ( this->get_alpha_mask != NULL )
230 return this->get_alpha_mask( this );
231 return test_card.alpha;
232 }
233
234 int mlt_frame_get_audio( mlt_frame this, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
235 {
236 if ( this->get_audio != NULL )
237 {
238 return this->get_audio( this, buffer, format, frequency, channels, samples );
239 }
240 else
241 {
242 if ( *samples <= 0 )
243 *samples = 1920;
244 if ( *channels <= 0 )
245 *channels = 2;
246 if ( *frequency <= 0 )
247 *frequency = 48000;
248 if ( test_card.audio == NULL || test_card.afmt != *format )
249 {
250 test_card.afmt = *format;
251 test_card.audio = realloc( test_card.audio, *samples * *channels * sizeof( int16_t ) );
252 memset( test_card.audio, 0, *samples * *channels * sizeof( int16_t ) );
253 }
254
255 *buffer = test_card.audio;
256 }
257 return 0;
258 }
259
260 void mlt_frame_close( mlt_frame this )
261 {
262 mlt_frame frame = mlt_frame_pop_frame( this );
263
264 while ( frame != NULL )
265 {
266 mlt_frame_close( frame);
267 frame = mlt_frame_pop_frame( this );
268 }
269
270 mlt_properties_close( &this->parent );
271
272 free( this );
273 }
274
275 /***** convenience functions *****/
276 #define RGB2YUV(r, g, b, y, u, v)\
277 y = (306*r + 601*g + 117*b) >> 10;\
278 u = ((-172*r - 340*g + 512*b) >> 10) + 128;\
279 v = ((512*r - 429*g - 83*b) >> 10) + 128;\
280 y = y < 0 ? 0 : y;\
281 u = u < 0 ? 0 : u;\
282 v = v < 0 ? 0 : v;\
283 y = y > 255 ? 255 : y;\
284 u = u > 255 ? 255 : u;\
285 v = v > 255 ? 255 : v
286
287 int mlt_convert_rgb24a_to_yuv422( uint8_t *rgba, int width, int height, int stride, uint8_t *yuv, uint8_t *alpha )
288 {
289 int ret = 0;
290 register int y0, y1, u0, u1, v0, v1;
291 register int r, g, b;
292 register uint8_t *d = yuv;
293 register int i, j;
294
295 for ( i = 0; i < height; i++ )
296 {
297 register uint8_t *s = rgba + ( stride * i );
298 for ( j = 0; j < ( width / 2 ); j++ )
299 {
300 r = *s++;
301 g = *s++;
302 b = *s++;
303 *alpha++ = *s++;
304 RGB2YUV (r, g, b, y0, u0 , v0);
305 r = *s++;
306 g = *s++;
307 b = *s++;
308 *alpha++ = *s++;
309 RGB2YUV (r, g, b, y1, u1 , v1);
310 *d++ = y0;
311 *d++ = (u0+u1) >> 1;
312 *d++ = y1;
313 *d++ = (v0+v1) >> 1;
314 }
315 if ( width % 2 )
316 {
317 r = *s++;
318 g = *s++;
319 b = *s++;
320 *alpha++ = *s++;
321 RGB2YUV (r, g, b, y0, u0 , v0);
322 *d++ = y0;
323 *d++ = u0;
324 }
325 }
326 return ret;
327 }
328
329 int mlt_convert_rgb24_to_yuv422( uint8_t *rgb, int width, int height, int stride, uint8_t *yuv )
330 {
331 int ret = 0;
332 register int y0, y1, u0, u1, v0, v1;
333 register int r, g, b;
334 register uint8_t *d = yuv;
335 register int i, j;
336
337 for ( i = 0; i < height; i++ )
338 {
339 register uint8_t *s = rgb + ( stride * i );
340 for ( j = 0; j < ( width / 2 ); j++ )
341 {
342 r = *s++;
343 g = *s++;
344 b = *s++;
345 RGB2YUV (r, g, b, y0, u0 , v0);
346 r = *s++;
347 g = *s++;
348 b = *s++;
349 RGB2YUV (r, g, b, y1, u1 , v1);
350 *d++ = y0;
351 *d++ = (u0+u1) >> 1;
352 *d++ = y1;
353 *d++ = (v0+v1) >> 1;
354 }
355 if ( width % 2 )
356 {
357 r = *s++;
358 g = *s++;
359 b = *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_yuv420p_to_yuv422( uint8_t *yuv420p, int width, int height, int stride, uint8_t *yuv )
369 {
370 int ret = 0;
371 register int i, j;
372
373 int half = width >> 1;
374
375 uint8_t *Y = yuv420p;
376 uint8_t *U = Y + width * height;
377 uint8_t *V = U + width * height / 4;
378
379 register uint8_t *d = yuv;
380
381 for ( i = 0; i < height; i++ )
382 {
383 register uint8_t *u = U + ( i / 2 ) * ( half );
384 register uint8_t *v = V + ( i / 2 ) * ( half );
385
386 for ( j = 0; j < half; j++ )
387 {
388 *d ++ = *Y ++;
389 *d ++ = *u ++;
390 *d ++ = *Y ++;
391 *d ++ = *v ++;
392 }
393 }
394 return ret;
395 }
396
397 int mlt_frame_composite_yuv( mlt_frame this, mlt_frame that, int x, int y, float weight )
398 {
399 int ret = 0;
400 int width_src = 0, height_src = 0;
401 int width_dest = 0, height_dest = 0;
402 mlt_image_format format_src = mlt_image_yuv422, format_dest = mlt_image_yuv422;
403 uint8_t *p_src, *p_dest;
404 int i, j;
405 int stride_src;
406 int stride_dest;
407 int x_src = 0, y_src = 0;
408
409 // optimization point - no work to do
410 if ( ( x < 0 && -x >= width_src ) || ( y < 0 && -y >= height_src ) )
411 return ret;
412
413 format_src = mlt_image_yuv422;
414 format_dest = mlt_image_yuv422;
415
416 //fprintf( stderr, "call get_image on frame a\n"), fflush( stderr );
417 mlt_frame_get_image( this, &p_dest, &format_dest, &width_dest, &height_dest, 1 /* writable */ );
418 //fprintf( stderr, "call get_image on frame b\n"), fflush( stderr );
419 mlt_frame_get_image( that, &p_src, &format_src, &width_src, &height_src, 0 /* writable */ );
420
421 //fprintf( stderr, "mlt_frame_composite_yuv %dx%d -> %dx%d\n", width_src, height_src, width_dest, height_dest );
422 //fflush(stderr);
423 //return ret;
424 stride_src = width_src * 2;
425 stride_dest = width_dest * 2;
426
427 // crop overlay off the left edge of frame
428 if ( x < 0 )
429 {
430 x_src = -x;
431 width_src -= x_src;
432 x = 0;
433 }
434
435 // crop overlay beyond right edge of frame
436 else if ( x + width_src > width_dest )
437 width_src = width_dest - x;
438
439 // crop overlay off the top edge of the frame
440 if ( y < 0 )
441 {
442 y_src = -y;
443 height_src -= y_src;
444 }
445 // crop overlay below bottom edge of frame
446 else if ( y + height_src > height_dest )
447 height_src = height_dest - y;
448
449 // offset pointer into overlay buffer based on cropping
450 p_src += x_src * 2 + y_src * stride_src;
451
452 // offset pointer into frame buffer based upon positive, even coordinates only!
453 // if ( interlaced && y % 2 )
454 // ++y;
455 p_dest += ( x < 0 ? 0 : x ) * 2 + ( y < 0 ? 0 : y ) * stride_dest;
456
457 // Get the alpha channel of the overlay
458 uint8_t *p_alpha = mlt_frame_get_alpha_mask( that );
459
460 // offset pointer into alpha channel based upon cropping
461 if ( p_alpha )
462 p_alpha += x_src + y_src * stride_src / 2;
463
464 // now do the compositing only to cropped extents
465 for ( i = 0; i < height_src; i++ )
466 {
467 uint8_t *p = p_src;
468 uint8_t *q = p_dest;
469 uint8_t *o = p_dest;
470 uint8_t *z = p_alpha;
471
472 for ( j = 0; j < width_src; j ++ )
473 {
474 uint8_t y = *p ++;
475 uint8_t uv = *p ++;
476 uint8_t a = ( z == NULL ) ? 255 : *z ++;
477 float value = ( weight * ( float ) a / 255.0 );
478 *o ++ = (uint8_t)( y * value + *q++ * ( 1 - value ) );
479 *o ++ = (uint8_t)( uv * value + *q++ * ( 1 - value ) );
480 }
481
482 p_src += stride_src;
483 p_dest += stride_dest;
484 if ( p_alpha )
485 p_alpha += stride_src / 2;
486 }
487
488 return ret;
489 }
490
491 void *memfill( void *dst, void *src, int l, int elements )
492 {
493 int i = 0;
494 if ( l == 2 )
495 {
496 uint8_t *p = dst;
497 uint8_t *src1 = src;
498 uint8_t *src2 = src + 1;
499 for ( i = 0; i < elements; i ++ )
500 {
501 *p ++ = *src1;
502 *p ++ = *src2;
503 }
504 dst = p;
505 }
506 else
507 {
508 for ( i = 0; i < elements; i ++ )
509 dst = memcpy( dst, src, l ) + l;
510 }
511 return dst;
512 }
513
514 void mlt_resize_yuv422( uint8_t *output, int owidth, int oheight, uint8_t *input, int iwidth, int iheight )
515 {
516 // Calculate strides
517 int istride = iwidth * 2;
518 int ostride = owidth * 2;
519
520 iwidth = iwidth - ( iwidth % 4 );
521 owidth = owidth - ( owidth % 4 );
522 iheight = iheight - ( iheight % 2 );
523 oheight = oheight - ( oheight % 2 );
524
525 // Coordinates (0,0 is middle of output)
526 int y;
527
528 // Calculate ranges
529 int out_x_range = owidth / 2;
530 int out_y_range = oheight / 2;
531 int in_x_range = iwidth / 2 < out_x_range ? iwidth / 2 : out_x_range;
532 int in_y_range = iheight / 2 < out_y_range ? iheight / 2 : out_y_range;
533
534 // Output pointers
535 uint8_t *out_line = output;
536 uint8_t *out_ptr = out_line;
537
538 // Calculate a middle and possibly invalid pointer in the input
539 uint8_t *in_middle = input + istride * ( iheight / 2 ) + ( iwidth / 2 ) * 2;
540 int in_line = - in_y_range * istride - in_x_range * 2;
541
542 uint8_t black[ 2 ] = { 16, 128 };
543
544 // Loop for the entirety of our output height.
545 for ( y = - out_y_range; y < out_y_range ; y ++ )
546 {
547 // Start at the beginning of the line
548 out_ptr = out_line;
549
550 if ( abs( y ) < iheight / 2 )
551 {
552 // Fill the outer part with black
553 out_ptr = memfill( out_ptr, black, 2, out_x_range - in_x_range );
554
555 // We're in the input range for this row.
556 memcpy( out_ptr, in_middle + in_line, 2 * iwidth );
557 out_ptr += 2 * iwidth;
558
559 // Fill the outer part with black
560 out_ptr = memfill( out_ptr, black, 2, out_x_range - in_x_range );
561
562 // Move to next input line
563 in_line += istride;
564 }
565 else
566 {
567 // Fill whole line with black
568 out_ptr = memfill( out_ptr, black, 2, owidth );
569 }
570
571 // Move to next output line
572 out_line += ostride;
573 }
574 }
575
576 /** A resizing function for yuv422 frames - this does not rescale, but simply
577 resizes. It assumes yuv422 images available on the frame so use with care.
578 */
579
580 uint8_t *mlt_frame_resize_yuv422( mlt_frame this, int owidth, int oheight )
581 {
582 // Get properties
583 mlt_properties properties = mlt_frame_properties( this );
584
585 // Get the input image, width and height
586 uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
587 int iwidth = mlt_properties_get_int( properties, "width" );
588 int iheight = mlt_properties_get_int( properties, "height" );
589
590 // If width and height are correct, don't do anything
591 if ( iwidth != owidth || iheight != oheight )
592 {
593 // Create the output image
594 uint8_t *output = malloc( owidth * oheight * 2 );
595
596 // Call the generic resize
597 mlt_resize_yuv422( output, owidth, oheight, input, iwidth, iheight );
598
599 // Now update the frame
600 mlt_properties_set_data( properties, "image", output, owidth * oheight * 2, free, NULL );
601 mlt_properties_set_int( properties, "width", owidth );
602 mlt_properties_set_int( properties, "height", oheight );
603
604 // Return the output
605 return output;
606 }
607
608 // No change, return input
609 return input;
610 }
611
612 /** A rescaling function for yuv422 frames - low quality, and provided for testing
613 only. It assumes yuv422 images available on the frame so use with care.
614 */
615
616 uint8_t *mlt_frame_rescale_yuv422( mlt_frame this, int owidth, int oheight )
617 {
618 // Get properties
619 mlt_properties properties = mlt_frame_properties( this );
620
621 // Get the input image, width and height
622 uint8_t *input = mlt_properties_get_data( properties, "image", NULL );
623 int iwidth = mlt_properties_get_int( properties, "width" );
624 int iheight = mlt_properties_get_int( properties, "height" );
625
626 // If width and height are correct, don't do anything
627 if ( iwidth != owidth || iheight != oheight )
628 {
629 // Create the output image
630 uint8_t *output = malloc( owidth * oheight * 2 );
631
632 // Calculate strides
633 int istride = iwidth * 2;
634 int ostride = owidth * 2;
635
636 iwidth = iwidth - ( iwidth % 4 );
637
638 // Coordinates (0,0 is middle of output)
639 int y, x;
640
641 // Derived coordinates
642 int dy, dx;
643
644 // Calculate ranges
645 int out_x_range = owidth / 2;
646 int out_y_range = oheight / 2;
647 int in_x_range = iwidth / 2;
648 int in_y_range = iheight / 2;
649
650 // Output pointers
651 uint8_t *out_line = output;
652 uint8_t *out_ptr;
653
654 // Calculate a middle pointer
655 uint8_t *in_middle = input + istride * in_y_range + in_x_range * 2;
656 uint8_t *in_line;
657 uint8_t *in_ptr;
658
659 // Generate the affine transform scaling values
660 float scale_width = ( float )iwidth / ( float )owidth;
661 float scale_height = ( float )iheight / ( float )oheight;
662
663 // Loop for the entirety of our output height.
664 for ( y = - out_y_range; y < out_y_range ; y ++ )
665 {
666 // Calculate the derived y value
667 dy = scale_height * y;
668
669 // Start at the beginning of the line
670 out_ptr = out_line;
671
672 // Pointer to the middle of the input line
673 in_line = in_middle + dy * istride;
674
675 // Loop for the entirety of our output row.
676 for ( x = - out_x_range; x < out_x_range; x += 1 )
677 {
678 // Calculated the derived x
679 dx = scale_width * x;
680
681 // Check if x and y are in the valid input range.
682 if ( abs( dx ) < in_x_range && abs( dy ) < in_y_range )
683 {
684 // We're in the input range for this row.
685 in_ptr = in_line + ( dx >> 1 ) * 4 + 2 * ( x & 1 );
686 *out_ptr ++ = *in_ptr ++;
687 *out_ptr ++ = *in_ptr ++;
688 }
689 else
690 {
691 // We're not in the input range for this row.
692 *out_ptr ++ = 16;
693 *out_ptr ++ = 128;
694 }
695 }
696
697 // Move to next output line
698 out_line += ostride;
699 }
700
701 // Now update the frame
702 mlt_properties_set_data( properties, "image", output, owidth * oheight * 2, free, NULL );
703 mlt_properties_set_int( properties, "width", owidth );
704 mlt_properties_set_int( properties, "height", oheight );
705
706 // Return the output
707 return output;
708 }
709
710 // No change, return input
711 return input;
712 }
713
714 int mlt_frame_mix_audio( mlt_frame this, mlt_frame that, float weight, int16_t **buffer, mlt_audio_format *format, int *frequency, int *channels, int *samples )
715 {
716 int ret = 0;
717 int16_t *p_src, *p_dest;
718 int16_t *src, *dest;
719 //static int16_t *extra_src = NULL, *extra_dest = NULL;
720 static int extra_src_samples = 0, extra_dest_samples = 0;
721 int frequency_src = 0, frequency_dest = 0;
722 int channels_src = 0, channels_dest = 0;
723 int samples_src = 0, samples_dest = 0;
724 int i, j;
725
726 mlt_frame_get_audio( this, &p_dest, format, &frequency_dest, &channels_dest, &samples_dest );
727 //fprintf( stderr, "frame dest samples %d channels %d position %f\n", samples_dest, channels_dest, mlt_properties_get_position( mlt_frame_properties( this ), "position" ) );
728 mlt_frame_get_audio( that, &p_src, format, &frequency_src, &channels_src, &samples_src );
729 //fprintf( stderr, "frame src samples %d channels %d\n", samples_src, channels_src );
730 if ( channels_src > 6 )
731 channels_src = 0;
732 if ( channels_dest > 6 )
733 channels_dest = 0;
734 if ( samples_src > 4000 )
735 samples_src = 0;
736 if ( samples_dest > 4000 )
737 samples_dest = 0;
738
739 #if 0
740 // Append new samples to leftovers
741 if ( extra_dest_samples > 0 )
742 {
743 fprintf( stderr, "prepending %d samples to dest\n", extra_dest_samples );
744 dest = realloc( extra_dest, ( samples_dest + extra_dest_samples ) * 2 * channels_dest );
745 memcpy( &extra_dest[ extra_dest_samples * channels_dest ], p_dest, samples_dest * 2 * channels_dest );
746 }
747 else
748 dest = p_dest;
749 if ( extra_src_samples > 0 )
750 {
751 fprintf( stderr, "prepending %d samples to src\n", extra_src_samples );
752 src = realloc( extra_src, ( samples_src + extra_src_samples ) * 2 * channels_src );
753 memcpy( &extra_src[ extra_src_samples * channels_src ], p_src, samples_src * 2 * channels_src );
754 }
755 else
756 src = p_src;
757 #else
758 src = p_src;
759 dest = p_dest;
760 #endif
761
762 // determine number of samples to process
763 if ( samples_src + extra_src_samples < samples_dest + extra_dest_samples )
764 *samples = samples_src + extra_src_samples;
765 else if ( samples_dest + extra_dest_samples < samples_src + extra_src_samples )
766 *samples = samples_dest + extra_dest_samples;
767
768 *channels = channels_src < channels_dest ? channels_src : channels_dest;
769 *buffer = p_dest;
770
771 // Mixdown
772 for ( i = 0; i < *samples; i++ )
773 {
774 for ( j = 0; j < *channels; j++ )
775 {
776 double d = (double) dest[ i * channels_dest + j ];
777 double s = (double) src[ i * channels_src + j ];
778 dest[ i * channels_dest + j ] = s * weight + d * ( 1.0 - weight );
779 }
780 }
781
782 // We have to copy --sigh
783 if ( dest != p_dest )
784 memcpy( p_dest, dest, *samples * 2 * *channels );
785
786 #if 0
787 // Store the leftovers
788 if ( samples_src + extra_src_samples < samples_dest + extra_dest_samples )
789 {
790 extra_dest_samples = ( samples_dest + extra_dest_samples ) - ( samples_src + extra_src_samples );
791 size_t size = extra_dest_samples * 2 * channels_dest;
792 fprintf( stderr, "storing %d samples from dest\n", extra_dest_samples );
793 if ( extra_dest )
794 free( extra_dest );
795 extra_dest = malloc( size );
796 if ( extra_dest )
797 memcpy( extra_dest, &p_dest[ ( samples_dest - extra_dest_samples - 1 ) * channels_dest ], size );
798 else
799 extra_dest_samples = 0;
800 }
801 else if ( samples_dest + extra_dest_samples < samples_src + extra_src_samples )
802 {
803 extra_src_samples = ( samples_src + extra_src_samples ) - ( samples_dest + extra_dest_samples );
804 size_t size = extra_src_samples * 2 * channels_src;
805 fprintf( stderr, "storing %d samples from src\n", extra_dest_samples );
806 if ( extra_src )
807 free( extra_src );
808 extra_src = malloc( size );
809 if ( extra_src )
810 memcpy( extra_src, &p_src[ ( samples_src - extra_src_samples - 1 ) * channels_src ], size );
811 else
812 extra_src_samples = 0;
813 }
814 #endif
815
816 return ret;
817 }
818
819 int mlt_sample_calculator( float fps, int frequency, int64_t position )
820 {
821 int samples = 0;
822
823 if ( fps > 29 && fps <= 30 )
824 {
825 samples = frequency / 30;
826
827 switch ( frequency )
828 {
829 case 48000:
830 if ( position % 5 != 0 )
831 samples += 2;
832 break;
833 case 44100:
834 if ( position % 300 == 0 )
835 samples = 1471;
836 else if ( position % 30 == 0 )
837 samples = 1470;
838 else if ( position % 2 == 0 )
839 samples = 1472;
840 else
841 samples = 1471;
842 break;
843 case 32000:
844 if ( position % 30 == 0 )
845 samples = 1068;
846 else if ( position % 29 == 0 )
847 samples = 1067;
848 else if ( position % 4 == 2 )
849 samples = 1067;
850 else
851 samples = 1068;
852 break;
853 default:
854 samples = 0;
855 }
856 }
857 else if ( fps != 0 )
858 {
859 samples = frequency / fps;
860 }
861
862 return samples;
863 }
864