2 * transition_composite.c -- compose one image over another using alpha channel
3 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
4 * Author: Dan Dennedy <dan@dennedy.org>
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.
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.
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.
21 #include "transition_composite.h"
22 #include <framework/mlt_frame.h>
33 int nw
; // normalised width
34 int nh
; // normalised height
35 int sw
; // scaled width, not including consumer scale based upon w/nw
36 int sh
; // scaled height, not including consumer scale based upon h/nh
42 int halign
; // horizontal alignment: 0=left, 1=center, 2=right
43 int valign
; // vertical alignment: 0=top, 1=middle, 2=bottom
46 /** Parse a value from a geometry string.
49 static float parse_value( char **ptr
, int normalisation
, char delim
, float defaults
)
51 float value
= defaults
;
53 if ( *ptr
!= NULL
&& **ptr
!= '\0' )
56 value
= strtod( *ptr
, &end
);
60 value
= ( value
/ 100.0 ) * normalisation
;
61 while ( *end
== delim
|| *end
== '%' )
70 /** Parse a geometry property string with the syntax X,Y:WxH:MIX. Any value can be
71 expressed as a percentage by appending a % after the value, otherwise values are
72 assumed to be relative to the normalised dimensions of the consumer.
75 static void geometry_parse( struct geometry_s
*geometry
, struct geometry_s
*defaults
, char *property
, int nw
, int nh
)
77 // Assign normalised width and height
81 // Assign from defaults if available
82 if ( defaults
!= NULL
)
84 geometry
->x
= defaults
->x
;
85 geometry
->y
= defaults
->y
;
86 geometry
->w
= geometry
->sw
= defaults
->w
;
87 geometry
->h
= geometry
->sh
= defaults
->h
;
88 geometry
->mix
= defaults
->mix
;
95 // Parse the geomtry string
96 if ( property
!= NULL
)
99 geometry
->x
= parse_value( &ptr
, nw
, ',', geometry
->x
);
100 geometry
->y
= parse_value( &ptr
, nh
, ':', geometry
->y
);
101 geometry
->w
= geometry
->sw
= parse_value( &ptr
, nw
, 'x', geometry
->w
);
102 geometry
->h
= geometry
->sh
= parse_value( &ptr
, nh
, ':', geometry
->h
);
103 geometry
->mix
= parse_value( &ptr
, 100, ' ', geometry
->mix
);
107 /** Calculate real geometry.
110 static void geometry_calculate( struct geometry_s
*output
, struct geometry_s
*in
, struct geometry_s
*out
, float position
)
112 // Calculate this frames geometry
115 output
->x
= in
->x
+ ( out
->x
- in
->x
) * position
+ 0.5;
116 output
->y
= in
->y
+ ( out
->y
- in
->y
) * position
+ 0.5;
117 output
->w
= in
->w
+ ( out
->w
- in
->w
) * position
;
118 output
->h
= in
->h
+ ( out
->h
- in
->h
) * position
;
119 output
->mix
= in
->mix
+ ( out
->mix
- in
->mix
) * position
;
122 /** Parse the alignment properties into the geometry.
125 static int alignment_parse( char* align
)
129 if ( align
== NULL
);
130 else if ( isdigit( align
[ 0 ] ) )
132 else if ( align
[ 0 ] == 'c' || align
[ 0 ] == 'm' )
134 else if ( align
[ 0 ] == 'r' || align
[ 0 ] == 'b' )
140 /** Adjust position according to scaled size and alignment properties.
143 static void alignment_calculate( struct geometry_s
*geometry
)
145 geometry
->x
+= ( geometry
->w
- geometry
->sw
) * geometry
->halign
/ 2 + 0.5;
146 geometry
->y
+= ( geometry
->h
- geometry
->sh
) * geometry
->valign
/ 2 + 0.5;
149 /** Calculate the position for this frame.
152 static float position_calculate( mlt_transition
this, mlt_frame frame
)
154 // Get the in and out position
155 mlt_position in
= mlt_transition_get_in( this );
156 mlt_position out
= mlt_transition_get_out( this );
158 // Get the position of the frame
159 mlt_position position
= mlt_frame_get_position( frame
);
162 return ( float )( position
- in
) / ( float )( out
- in
+ 1 );
165 /** Calculate the field delta for this frame - position between two frames.
168 static float delta_calculate( mlt_transition
this, mlt_frame frame
)
170 // Get the in and out position
171 mlt_position in
= mlt_transition_get_in( this );
172 mlt_position out
= mlt_transition_get_out( this );
174 // Get the position of the frame
175 mlt_position position
= mlt_frame_get_position( frame
);
178 float x
= ( float )( position
- in
) / ( float )( out
- in
+ 1 );
180 float y
= ( float )( position
- in
) / ( float )( out
- in
+ 1 );
182 return ( y
- x
) / 2.0;
185 static int get_value( mlt_properties properties
, char *preferred
, char *fallback
)
187 int value
= mlt_properties_get_int( properties
, preferred
);
189 value
= mlt_properties_get_int( properties
, fallback
);
193 /** Composite function.
196 static int composite_yuv( uint8_t *p_dest
, int width_dest
, int height_dest
, int bpp
, uint8_t *p_src
, int width_src
, int height_src
, uint8_t *p_alpha
, struct geometry_s geometry
, int field
)
200 int x_src
= 0, y_src
= 0;
201 float weight
= geometry
.mix
/ 100;
202 int stride_src
= width_src
* bpp
;
203 int stride_dest
= width_dest
* bpp
;
205 // Adjust to consumer scale
206 int x
= geometry
.x
* width_dest
/ geometry
.nw
+ 0.5;
207 int y
= geometry
.y
* height_dest
/ geometry
.nh
+ 0.5;
212 // optimization points - no work to do
213 if ( width_src
<= 0 || height_src
<= 0 )
216 if ( ( x
< 0 && -x
>= width_src
) || ( y
< 0 && -y
>= height_src
) )
219 // crop overlay off the left edge of frame
227 // crop overlay beyond right edge of frame
228 else if ( x
+ width_src
> width_dest
)
229 width_src
= width_dest
- x
;
231 // crop overlay off the top edge of the frame
237 // crop overlay below bottom edge of frame
238 else if ( y
+ height_src
> height_dest
)
239 height_src
= height_dest
- y
;
241 // offset pointer into overlay buffer based on cropping
242 p_src
+= x_src
* bpp
+ y_src
* stride_src
;
244 // offset pointer into frame buffer based upon positive coordinates only!
245 p_dest
+= ( x
< 0 ?
0 : x
) * bpp
+ ( y
< 0 ?
0 : y
) * stride_dest
;
247 // offset pointer into alpha channel based upon cropping
249 p_alpha
+= x_src
+ y_src
* stride_src
/ bpp
;
251 // Assuming lower field first
252 // Special care is taken to make sure the b_frame is aligned to the correct field.
253 // field 0 = lower field and y should be odd (y is 0-based).
254 // field 1 = upper field and y should be even.
255 if ( ( field
> -1 ) && ( y
% 2 == field
) )
257 //fprintf( stderr, "field %d y %d\n", field, y );
258 if ( ( field
== 1 && y
< height_dest
- 1 ) || ( field
== 0 && y
== 0 ) )
259 p_dest
+= stride_dest
;
261 p_dest
-= stride_dest
;
264 // On the second field, use the other lines from b_frame
269 p_alpha
+= stride_src
/ bpp
;
276 uint8_t *z
= p_alpha
;
280 int step
= ( field
> -1 ) ?
2 : 1;
282 // now do the compositing only to cropped extents
283 for ( i
= 0; i
< height_src
; i
+= step
)
285 p
= &p_src
[ i
* stride_src
];
286 q
= &p_dest
[ i
* stride_dest
];
287 o
= &p_dest
[ i
* stride_dest
];
289 z
= &p_alpha
[ i
* stride_src
/ bpp
];
291 for ( j
= 0; j
< width_src
; j
++ )
293 a
= ( z
== NULL
) ?
255 : *z
++;
294 value
= ( weight
* ( float ) a
/ 255.0 );
295 for ( k
= 0; k
< bpp
; k
++ )
296 *o
++ = (uint8_t)( *p
++ * value
+ *q
++ * ( 1 - value
) );
304 /** Get the properly sized image from b_frame.
307 static int get_b_frame_image( mlt_frame b_frame
, uint8_t **image
, int *width
, int *height
, struct geometry_s
*geometry
)
310 mlt_image_format format
= mlt_image_yuv422
;
312 // Initialise the scaled dimensions from the computed
313 geometry
->sw
= geometry
->w
;
314 geometry
->sh
= geometry
->h
;
316 // Compute the dimensioning rectangle
317 mlt_properties b_props
= mlt_frame_properties( b_frame
);
318 mlt_transition
this = mlt_properties_get_data( b_props
, "transition_composite", NULL
);
319 mlt_properties properties
= mlt_transition_properties( this );
321 if ( mlt_properties_get( properties
, "distort" ) == NULL
)
323 // Adjust b_frame pixel aspect
324 int normalised_width
= geometry
->w
;
325 int normalised_height
= geometry
->h
;
326 int real_width
= get_value( b_props
, "real_width", "width" );
327 int real_height
= get_value( b_props
, "real_height", "height" );
328 double input_ar
= mlt_frame_get_aspect_ratio( b_frame
);
329 double output_ar
= mlt_properties_get_double( b_props
, "consumer_aspect_ratio" );
330 //int scaled_width = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_width;
331 //int scaled_height = ( input_ar > output_ar ? input_ar / output_ar : output_ar / input_ar ) * real_height;
332 int scaled_width
= real_width
;
333 int scaled_height
= real_height
;
334 double output_sar
= ( double ) geometry
->nw
/ geometry
->nh
/ output_ar
;
336 // We always normalise pixel aspect by requesting a larger than normal
337 // image in order to maximise usage of the bounding rectangle
339 // These calcs are optimised by reducing factors in equations
340 // This is disabled due to bad results on 480 wide MPEGs
342 if ( output_sar
< 1.0 )
343 // If the output is skinny pixels (PAL) then stretch our input vertically
344 // derived from: input_sar / output_sar * real_height
345 scaled_height
= ( double )real_width
/ input_ar
/ output_sar
;
349 // If the output is fat pixels (NTSC) then stretch our input horizontally
350 // derived from: output_sar / input_sar * real_width
351 scaled_width
= output_sar
* real_height
* input_ar
;
353 // fprintf( stderr, "composite: real %dx%d scaled %dx%d normalised %dx%d\n", real_width, real_height, scaled_width, scaled_height, normalised_width, normalised_height );
355 // Now ensure that our images fit in the normalised frame
356 if ( scaled_width
> normalised_width
)
358 scaled_height
= scaled_height
* normalised_width
/ scaled_width
;
359 scaled_width
= normalised_width
;
361 if ( scaled_height
> normalised_height
)
363 scaled_width
= scaled_width
* normalised_height
/ scaled_height
;
364 scaled_height
= normalised_height
;
367 // Now we need to align to the geometry
368 if ( scaled_width
<= geometry
->w
&& scaled_height
<= geometry
->h
)
370 // Save the new scaled dimensions
371 geometry
->sw
= scaled_width
;
372 geometry
->sh
= scaled_height
;
376 // We want to ensure that we bypass resize now...
377 mlt_properties_set( b_props
, "distort", "true" );
379 // Take into consideration alignment for optimisation
380 alignment_calculate( geometry
);
382 // Adjust to consumer scale
383 int x
= geometry
->x
* *width
/ geometry
->nw
+ 0.5;
384 int y
= geometry
->y
* *height
/ geometry
->nh
+ 0.5;
385 *width
= geometry
->sw
* *width
/ geometry
->nw
;
386 *height
= geometry
->sh
* *height
/ geometry
->nh
;
390 //fprintf( stderr, "composite calculated %d,%d:%dx%d\n", x, y, *width, *height );
392 // optimization points - no work to do
393 if ( *width
<= 0 || *height
<= 0 )
396 if ( ( x
< 0 && -x
>= *width
) || ( y
< 0 && -y
>= *height
) )
399 ret
= mlt_frame_get_image( b_frame
, image
, &format
, width
, height
, 1 /* writable */ );
405 static uint8_t *transition_get_alpha_mask( mlt_frame
this )
407 // Obtain properties of frame
408 mlt_properties properties
= mlt_frame_properties( this );
410 // Return the alpha mask
411 return mlt_properties_get_data( properties
, "alpha", NULL
);
417 static int transition_get_image( mlt_frame a_frame
, uint8_t **image
, mlt_image_format
*format
, int *width
, int *height
, int writable
)
419 // Get the b frame from the stack
420 mlt_frame b_frame
= mlt_frame_pop_frame( a_frame
);
422 // This compositer is yuv422 only
423 *format
= mlt_image_yuv422
;
425 // Get the image from the a frame
426 mlt_frame_get_image( a_frame
, image
, format
, width
, height
, 1 );
428 if ( b_frame
!= NULL
)
430 // Get the properties of the a frame
431 mlt_properties a_props
= mlt_frame_properties( a_frame
);
433 // Get the properties of the b frame
434 mlt_properties b_props
= mlt_frame_properties( b_frame
);
436 // Get the transition from the b frame
437 mlt_transition
this = mlt_properties_get_data( b_props
, "transition_composite", NULL
);
439 // Get the properties from the transition
440 mlt_properties properties
= mlt_transition_properties( this );
442 // Structures for geometry
443 struct geometry_s result
;
444 struct geometry_s start
;
445 struct geometry_s end
;
447 // Calculate the position
448 float position
= position_calculate( this, a_frame
);
449 float delta
= delta_calculate( this, a_frame
);
451 // Obtain the normalised width and height from the a_frame
452 int normalised_width
= mlt_properties_get_int( a_props
, "normalised_width" );
453 int normalised_height
= mlt_properties_get_int( a_props
, "normalised_height" );
455 // Now parse the geometries
456 geometry_parse( &start
, NULL
, mlt_properties_get( properties
, "start" ), normalised_width
, normalised_height
);
457 geometry_parse( &end
, &start
, mlt_properties_get( properties
, "end" ), normalised_width
, normalised_height
);
459 // Now parse the alignment
460 result
.halign
= alignment_parse( mlt_properties_get( properties
, "halign" ) );
461 result
.valign
= alignment_parse( mlt_properties_get( properties
, "valign" ) );
463 // Since we are the consumer of the b_frame, we must pass along these
464 // consumer properties from the a_frame
465 mlt_properties_set_double( b_props
, "consumer_aspect_ratio", mlt_properties_get_double( a_props
, "consumer_aspect_ratio" ) );
466 mlt_properties_set_double( b_props
, "consumer_scale", mlt_properties_get_double( a_props
, "consumer_scale" ) );
468 // Do the calculation
469 geometry_calculate( &result
, &start
, &end
, position
);
471 // Get the image from the b frame
473 int width_b
= *width
;
474 int height_b
= *height
;
476 if ( get_b_frame_image( b_frame
, &image_b
, &width_b
, &height_b
, &result
) == 0 )
478 uint8_t *dest
= *image
;
479 uint8_t *src
= image_b
;
481 uint8_t *alpha
= mlt_frame_get_alpha_mask( b_frame
);
482 int progressive
= mlt_properties_get_int( a_props
, "progressive" ) ||
483 mlt_properties_get_int( a_props
, "consumer_progressive" ) ||
484 mlt_properties_get_int( properties
, "progressive" );
487 // See if the alpha channel is our destination
488 if ( mlt_properties_get( properties
, "a_frame" ) != NULL
)
492 // Get or make the a_frame alpha channel
493 dest
= mlt_frame_get_alpha_mask( a_frame
);
496 // Allocate the alpha
497 dest
= mlt_pool_alloc( *width
* *height
);
498 mlt_properties_set_data( a_props
, "alpha", dest
, *width
* *height
, ( mlt_destructor
)mlt_pool_release
, NULL
);
500 // Set alpha call back
501 a_frame
->get_alpha_mask
= transition_get_alpha_mask
;
504 // If the source is an image, convert its YUV to an alpha channel
505 if ( mlt_properties_get( properties
, "b_frame" ) == NULL
)
509 // Allocate the alpha
510 alpha
= mlt_pool_alloc( width_b
* height_b
);
511 mlt_properties_set_data( b_props
, "alpha", alpha
, width_b
* height_b
, ( mlt_destructor
)mlt_pool_release
, NULL
);
513 // Set alpha call back
514 b_frame
->get_alpha_mask
= transition_get_alpha_mask
;
517 // Copy the Y values into alpha
518 uint8_t *p
= image_b
;
521 for ( i
= 0; i
< width_b
* height_b
; i
++, p
+= 2 )
524 // Setup to composite from the alpha channel
530 // See if the alpha channel is our source
531 if ( mlt_properties_get( properties
, "b_frame" ) != NULL
)
533 // If we do not have an alpha channel fabricate it
536 // Allocate the alpha
537 alpha
= mlt_pool_alloc( width_b
* height_b
);
538 mlt_properties_set_data( b_props
, "alpha", alpha
, width_b
* height_b
, ( mlt_destructor
)mlt_pool_release
, NULL
);
540 // Set alpha call back
541 b_frame
->get_alpha_mask
= transition_get_alpha_mask
;
543 // Copy the Y values into alpha
544 uint8_t *p
= image_b
;
547 for ( i
= 0; i
< width_b
* height_b
; i
++, p
+= 2 )
551 // If the destination is image, convert the alpha channel to YUV
552 if ( mlt_properties_get( properties
, "a_frame" ) == NULL
)
555 uint8_t *q
= image_b
;
558 for ( i
= 0; i
< width_b
* height_b
; i
++, p
++ )
560 *q
++ = 16 + ( ( float )*p
/ 255 * 219 ); // 220 is the luma range from 16-235
566 // Setup to composite from the alpha channel
571 // Never the apply the alpha channel to this type of operation
575 for ( field
= 0; field
< ( progressive ?
1 : 2 ); field
++ )
577 // Assume lower field (0) first
578 float field_position
= position
+ field
* delta
;
580 // Do the calculation
581 geometry_calculate( &result
, &start
, &end
, field_position
);
584 alignment_calculate( &result
);
586 // Composite the b_frame on the a_frame
587 composite_yuv( dest
, *width
, *height
, bpp
, src
, width_b
, height_b
, alpha
, result
, progressive ?
-1 : field
);
595 /** Composition transition processing.
598 static mlt_frame
composite_process( mlt_transition
this, mlt_frame a_frame
, mlt_frame b_frame
)
600 // Propogate the transition properties to the b frame
601 mlt_properties b_props
= mlt_frame_properties( b_frame
);
602 mlt_properties_set_data( b_props
, "transition_composite", this, 0, NULL
, NULL
);
603 mlt_frame_push_get_image( a_frame
, transition_get_image
);
604 mlt_frame_push_frame( a_frame
, b_frame
);
608 /** Constructor for the filter.
611 mlt_transition
transition_composite_init( char *arg
)
613 mlt_transition
this = calloc( sizeof( struct mlt_transition_s
), 1 );
614 if ( this != NULL
&& mlt_transition_init( this, NULL
) == 0 )
616 this->process
= composite_process
;
617 mlt_properties_set( mlt_transition_properties( this ), "start", arg
!= NULL ? arg
: "85%,5%:10%x10%" );
618 mlt_properties_set( mlt_transition_properties( this ), "end", "" );