2 * filter_obscure.c -- obscure filter
3 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
4 * Author: Charles Yates <charles.yates@pandora.be>
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 "filter_obscure.h"
23 #include <framework/mlt_frame.h>
24 #include <framework/mlt_deque.h>
44 /** Parse a value from a geometry string.
47 static float parse_value( char **ptr
, int normalisation
, char delim
, float defaults
)
49 float value
= defaults
;
51 if ( *ptr
!= NULL
&& **ptr
!= '\0' )
54 value
= strtod( *ptr
, &end
);
58 value
= ( value
/ 100.0 ) * normalisation
;
59 while ( *end
== delim
|| *end
== '%' )
68 /** Parse a geometry property string.
71 static void geometry_parse( struct geometry_s
*geometry
, struct geometry_s
*defaults
, char *property
, int nw
, int nh
)
73 // Assign normalised width and height
77 // Assign from defaults if available
78 if ( defaults
!= NULL
)
80 geometry
->x
= defaults
->x
;
81 geometry
->y
= defaults
->y
;
82 geometry
->w
= defaults
->w
;
83 geometry
->h
= defaults
->h
;
84 geometry
->mask_w
= defaults
->mask_w
;
85 geometry
->mask_h
= defaults
->mask_h
;
89 geometry
->mask_w
= 20;
90 geometry
->mask_h
= 20;
93 // Parse the geomtry string
94 if ( property
!= NULL
)
97 geometry
->x
= parse_value( &ptr
, nw
, ',', geometry
->x
);
98 geometry
->y
= parse_value( &ptr
, nh
, ':', geometry
->y
);
99 geometry
->w
= parse_value( &ptr
, nw
, 'x', geometry
->w
);
100 geometry
->h
= parse_value( &ptr
, nh
, ':', geometry
->h
);
101 geometry
->mask_w
= parse_value( &ptr
, nw
, 'x', geometry
->mask_w
);
102 geometry
->mask_h
= parse_value( &ptr
, nh
, ' ', geometry
->mask_h
);
106 /** A Timism but not as clean ;-).
109 static float lerp( float value
, float lower
, float upper
)
113 else if ( value
> upper
)
118 /** Calculate real geometry.
121 static void geometry_calculate( struct geometry_s
*output
, struct geometry_s
*in
, struct geometry_s
*out
, float position
, int ow
, int oh
)
123 // Calculate this frames geometry
124 output
->x
= lerp( ( in
->x
+ ( out
->x
- in
->x
) * position
) / ( float )out
->nw
* ow
, 0, ow
);
125 output
->y
= lerp( ( in
->y
+ ( out
->y
- in
->y
) * position
) / ( float )out
->nh
* oh
, 0, oh
);
126 output
->w
= lerp( ( in
->w
+ ( out
->w
- in
->w
) * position
) / ( float )out
->nw
* ow
, 0, ow
- output
->x
);
127 output
->h
= lerp( ( in
->h
+ ( out
->h
- in
->h
) * position
) / ( float )out
->nh
* oh
, 0, oh
- output
->y
);
128 output
->mask_w
= in
->mask_w
+ ( out
->mask_w
- in
->mask_w
) * position
;
129 output
->mask_h
= in
->mask_h
+ ( out
->mask_h
- in
->mask_h
) * position
;
132 /** Calculate the position for this frame.
135 static float position_calculate( mlt_filter
this, mlt_frame frame
)
137 // Get the in and out position
138 mlt_position in
= mlt_filter_get_in( this );
139 mlt_position out
= mlt_filter_get_out( this );
141 // Get the position of the frame
142 mlt_position position
= mlt_frame_get_position( frame
);
145 return ( float )( position
- in
) / ( float )( out
- in
+ 1 );
148 /** The averaging function...
151 void obscure_average( uint8_t *start
, int width
, int height
, int stride
)
155 register int Y
= ( *start
+ *( start
+ 2 ) ) / 2;
156 register int U
= *( start
+ 1 );
157 register int V
= *( start
+ 3 );
160 for ( y
= 0; y
< height
; y
++ )
162 p
= start
+ y
* stride
;
163 for ( x
= 0; x
< width
/ 2; x
++ )
165 Y
= ( Y
+ *p
++ ) / 2;
166 U
= ( U
+ *p
++ ) / 2;
167 Y
= ( Y
+ *p
++ ) / 2;
168 V
= ( V
+ *p
++ ) / 2;
172 for ( y
= 0; y
< height
; y
++ )
174 p
= start
+ y
* stride
;
176 for ( x
= 0; x
< width
/ 2; x
++ )
187 /** The obscurer rendering function...
190 static void obscure_render( uint8_t *image
, int width
, int height
, struct geometry_s result
)
192 int area_x
= result
.x
;
193 int area_y
= result
.y
;
194 int area_w
= result
.w
;
195 int area_h
= result
.h
;
197 int mw
= result
.mask_w
;
198 int mh
= result
.mask_h
;
204 uint8_t *p
= image
+ area_y
* width
* 2 + area_x
* 2;
206 for ( w
= 0; w
< area_w
; w
+= mw
)
208 for ( h
= 0; h
< area_h
; h
+= mh
)
210 aw
= w
+ mw
> area_w ? mw
- ( w
+ mw
- area_w
) : mw
;
211 ah
= h
+ mh
> area_h ? mh
- ( h
+ mh
- area_h
) : mh
;
212 if ( aw
> 1 && ah
> 1 )
213 obscure_average( p
+ h
* width
* 2 + w
* 2, aw
, ah
, width
* 2 );
221 static int filter_get_image( mlt_frame frame
, uint8_t **image
, mlt_image_format
*format
, int *width
, int *height
, int writable
)
223 // Get the frame properties
224 mlt_properties frame_properties
= mlt_frame_properties( frame
);
226 // Fetch the obscure stack for this frame
227 mlt_deque deque
= mlt_properties_get_data( frame_properties
, "filter_obscure", NULL
);
229 // Pop the top of stack now
230 mlt_filter
this = mlt_deque_pop_back( deque
);
232 // Get the image from the frame
233 if ( mlt_frame_get_image( frame
, image
, format
, width
, height
, 1 ) == 0 )
237 // Get the filter properties
238 mlt_properties properties
= mlt_filter_properties( this );
240 // Obtain the normalised width and height from the frame
241 int normalised_width
= mlt_properties_get_int( frame_properties
, "normalised_width" );
242 int normalised_height
= mlt_properties_get_int( frame_properties
, "normalised_height" );
244 // Structures for geometry
245 struct geometry_s result
;
246 struct geometry_s start
;
247 struct geometry_s end
;
249 // Calculate the position
250 float position
= position_calculate( this, frame
);
252 // Now parse the geometries
253 geometry_parse( &start
, NULL
, mlt_properties_get( properties
, "start" ), normalised_width
, normalised_height
);
254 geometry_parse( &end
, &start
, mlt_properties_get( properties
, "end" ), normalised_width
, normalised_height
);
256 // Do the calculation
257 geometry_calculate( &result
, &start
, &end
, position
, *width
, *height
);
259 // Now actually render it
260 obscure_render( *image
, *width
, *height
, result
);
267 /** Filter processing.
270 static mlt_frame
filter_process( mlt_filter
this, mlt_frame frame
)
272 // Get the frame properties
273 mlt_properties frame_properties
= mlt_frame_properties( frame
);
275 // Fetch the obscure stack for this frame
276 mlt_deque deque
= mlt_properties_get_data( frame_properties
, "filter_obscure", NULL
);
278 // Create stack if necessary
282 deque
= mlt_deque_init( );
284 // Assign to the frame
285 mlt_properties_set_data( frame_properties
, "filter_obscure", deque
, 0, ( mlt_destructor
)mlt_deque_close
, NULL
);
288 // Push this on to the obscure stack
289 mlt_deque_push_back( deque
, this );
291 // Push the get image call
292 mlt_frame_push_get_image( frame
, filter_get_image
);
297 /** Constructor for the filter.
300 mlt_filter
filter_obscure_init( void *arg
)
302 mlt_filter
this = mlt_filter_new( );
305 mlt_properties properties
= mlt_filter_properties( this );
306 this->process
= filter_process
;
307 mlt_properties_set( properties
, "start", arg
!= NULL ? arg
: "0%,0%:100%x100%" );
308 mlt_properties_set( properties
, "end", "" );