2 * filter_rescale.c -- scale the producer video frame size to match the consumer
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 "filter_rescale.h"
23 #include <framework/mlt_frame.h>
29 typedef int ( *image_scaler
)( mlt_frame
this, uint8_t **image
, mlt_image_format iformat
, mlt_image_format oformat
, int iwidth
, int iheight
, int owidth
, int oheight
);
31 static int filter_scale( mlt_frame
this, uint8_t **image
, mlt_image_format iformat
, mlt_image_format oformat
, int iwidth
, int iheight
, int owidth
, int oheight
)
34 mlt_properties properties
= MLT_FRAME_PROPERTIES( this );
36 // Get the rescaling interpolsation
37 char *interps
= mlt_properties_get( properties
, "rescale.interp" );
39 // Carry out the rescaling
40 if ( iformat
== mlt_image_yuv422
&& oformat
== mlt_image_yuv422
)
43 mlt_frame_rescale_yuv422( this, owidth
, oheight
);
46 *image
= mlt_properties_get_data( properties
, "image", NULL
);
48 else if ( iformat
== mlt_image_rgb24
|| iformat
== mlt_image_rgb24a
)
50 int bpp
= (iformat
== mlt_image_rgb24a ?
4 : 3 );
52 // Create the yuv image
53 uint8_t *output
= mlt_pool_alloc( iwidth
* ( iheight
+ 1 ) * 2 );
55 if ( strcmp( interps
, "none" ) && ( iwidth
!= owidth
|| iheight
!= oheight
) )
57 // Extract YUV422 and alpha
60 // Allocate the alpha mask
61 uint8_t *alpha
= mlt_pool_alloc( iwidth
* ( iheight
+ 1 ) );
63 // Convert the image and extract alpha
64 mlt_convert_rgb24a_to_yuv422( *image
, iwidth
, iheight
, iwidth
* 2, output
, alpha
);
66 mlt_properties_set_data( properties
, "alpha", alpha
, iwidth
* ( iheight
+ 1 ), ( mlt_destructor
)mlt_pool_release
, NULL
);
70 // No alpha to extract
71 mlt_convert_rgb24_to_yuv422( *image
, iwidth
, iheight
, iwidth
* 2, output
);
75 mlt_frame_rescale_yuv422( this, owidth
, oheight
);
78 *image
= mlt_properties_get_data( properties
, "image", NULL
);
82 // Extract YUV422 and alpha
85 // Allocate the alpha mask
86 uint8_t *alpha
= mlt_pool_alloc( owidth
* ( oheight
+ 1 ) );
88 // Convert the image and extract alpha
89 mlt_convert_rgb24a_to_yuv422( *image
, owidth
, oheight
, owidth
* 4, output
, alpha
);
91 mlt_properties_set_data( properties
, "alpha", alpha
, owidth
* ( oheight
+ 1 ), ( mlt_destructor
)mlt_pool_release
, NULL
);
95 // No alpha to extract
96 mlt_convert_rgb24_to_yuv422( *image
, owidth
, oheight
, owidth
* 3, output
);
100 // Now update the frame
101 mlt_properties_set_data( properties
, "image", output
, owidth
* ( oheight
+ 1 ) * 2, ( mlt_destructor
)mlt_pool_release
, NULL
);
102 mlt_properties_set_int( properties
, "width", owidth
);
103 mlt_properties_set_int( properties
, "height", oheight
);
111 static void scale_alpha( mlt_frame
this, int iwidth
, int iheight
, int owidth
, int oheight
)
114 uint8_t *input
= mlt_properties_get_data( MLT_FRAME_PROPERTIES( this ), "alpha", &size
);
116 if ( input
!= NULL
&& ( size
== iwidth
* iheight
) || size
== ( iwidth
* ( iheight
+ 1 ) ) )
118 uint8_t *output
= mlt_pool_alloc( owidth
* oheight
);
120 // Derived coordinates
124 int out_x_range
= owidth
/ 2;
125 int out_y_range
= oheight
/ 2;
126 int in_x_range
= iwidth
/ 2;
127 int in_y_range
= iheight
/ 2;
130 register uint8_t *out_line
= output
;
131 register uint8_t *out_ptr
;
133 // Calculate a middle pointer
134 uint8_t *in_middle
= input
+ iwidth
* in_y_range
+ in_x_range
;
137 // Generate the affine transform scaling values
138 register int scale_width
= ( iwidth
<< 16 ) / owidth
;
139 register int scale_height
= ( iheight
<< 16 ) / oheight
;
140 register int base
= 0;
142 int outer
= out_x_range
* scale_width
;
143 int bottom
= out_y_range
* scale_height
;
145 // Loop for the entirety of our output height.
146 for ( dy
= - bottom
; dy
< bottom
; dy
+= scale_height
)
148 // Start at the beginning of the line
151 // Pointer to the middle of the input line
152 in_line
= in_middle
+ ( dy
>> 16 ) * iwidth
;
154 // Loop for the entirety of our output row.
155 for ( dx
= - outer
; dx
< outer
; dx
+= scale_width
)
158 *out_ptr
++ = *( in_line
+ base
);
161 // Move to next output line
165 this->get_alpha_mask
= NULL
;
166 mlt_properties_set_data( MLT_FRAME_PROPERTIES( this ), "alpha", output
, 0, mlt_pool_release
, NULL
);
173 static int filter_get_image( mlt_frame
this, uint8_t **image
, mlt_image_format
*format
, int *width
, int *height
, int writable
)
175 // Get the frame properties
176 mlt_properties properties
= MLT_FRAME_PROPERTIES( this );
178 // Get the filter from the stack
179 mlt_filter filter
= mlt_frame_pop_service( this );
181 // Get the filter properties
182 mlt_properties filter_properties
= MLT_FILTER_PROPERTIES( filter
);
184 // Get the image scaler method
185 image_scaler scaler_method
= mlt_properties_get_data( filter_properties
, "method", NULL
);
187 // Correct Width/height if necessary
188 if ( *width
== 0 || *height
== 0 )
190 *width
= mlt_properties_get_int( properties
, "normalised_width" );
191 *height
= mlt_properties_get_int( properties
, "normalised_height" );
194 // There can be problems with small images - avoid them (by hacking - gah)
195 if ( *width
>= 6 && *height
>= 6 )
198 int iheight
= *height
;
200 int oheight
= *height
;
201 char *interps
= mlt_properties_get( properties
, "rescale.interp" );
202 int wanted_format
= *format
;
204 // Default from the scaler if not specifed on the frame
205 if ( interps
== NULL
)
207 interps
= mlt_properties_get( MLT_FILTER_PROPERTIES( filter
), "interpolation" );
208 mlt_properties_set( properties
, "rescale.interp", interps
);
211 // If real_width/height exist, we want that as minimum information
212 if ( mlt_properties_get_int( properties
, "real_width" ) )
214 iwidth
= mlt_properties_get_int( properties
, "real_width" );
215 iheight
= mlt_properties_get_int( properties
, "real_height" );
218 // Let the producer know what we are actually requested to obtain
219 if ( *format
== mlt_image_yuv422
&& strcmp( interps
, "none" ) )
221 mlt_properties_set_int( properties
, "rescale_width", *width
);
222 mlt_properties_set_int( properties
, "rescale_height", *height
);
226 // When no scaling is requested, revert the requested dimensions if possible
227 mlt_properties_set_int( properties
, "rescale_width", ( iwidth
/ 2 ) * 2 );
228 mlt_properties_set_int( properties
, "rescale_height", iheight
);
231 // Get the image as requested
232 mlt_frame_get_image( this, image
, format
, &iwidth
, &iheight
, writable
);
234 // Get rescale interpretation again, in case the producer wishes to override scaling
235 interps
= mlt_properties_get( properties
, "rescale.interp" );
237 if ( *image
!= NULL
&& ( *format
!= mlt_image_yuv422
|| ( iwidth
!= owidth
|| iheight
!= oheight
) ) )
239 // If the colour space is correct and scaling is off, do nothing
240 if ( *format
== mlt_image_yuv422
&& !strcmp( interps
, "none" ) )
245 else if ( *format
== mlt_image_yuv422
)
247 // Call the local scaler
248 scaler_method( this, image
, *format
, mlt_image_yuv422
, iwidth
, iheight
, owidth
, oheight
);
253 scale_alpha( this, iwidth
, iheight
, owidth
, oheight
);
255 else if ( *format
== mlt_image_rgb24
&& wanted_format
== mlt_image_rgb24
)
257 // Call the local scaler
258 scaler_method( this, image
, *format
, mlt_image_rgb24
, iwidth
, iheight
, owidth
, oheight
);
265 scale_alpha( this, iwidth
, iheight
, owidth
, oheight
);
267 else if ( *format
== mlt_image_rgb24
|| *format
== mlt_image_rgb24a
)
269 // Call the local scaler
270 scaler_method( this, image
, *format
, mlt_image_yuv422
, iwidth
, iheight
, owidth
, oheight
);
273 *format
= mlt_image_yuv422
;
278 scale_alpha( this, iwidth
, iheight
, owidth
, oheight
);
294 // Store the requested width/height
296 int iheight
= *height
;
298 // Get the image as requested
299 mlt_frame_get_image( this, image
, format
, &iwidth
, &iheight
, writable
);
301 // Too small - for now just assign as though we got what we wanted
310 /** Filter processing.
313 static mlt_frame
filter_process( mlt_filter
this, mlt_frame frame
)
316 mlt_frame_push_service( frame
, this );
318 // Push the get image method
319 mlt_frame_push_service( frame
, filter_get_image
);
324 /** Constructor for the filter.
327 mlt_filter
filter_rescale_init( char *arg
)
329 // Create a new scaler
330 mlt_filter
this = mlt_filter_new( );
332 // If successful, then initialise it
335 // Get the properties
336 mlt_properties properties
= MLT_FILTER_PROPERTIES( this );
338 // Set the process method
339 this->process
= filter_process
;
341 // Set the inerpolation
342 mlt_properties_set( properties
, "interpolation", arg
== NULL ?
"bilinear" : arg
);
345 mlt_properties_set_data( properties
, "method", filter_scale
, 0, NULL
, NULL
);