2 * filter_resize.c -- resizing 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_resize.h"
23 #include <framework/mlt_frame.h>
29 static int get_value( mlt_properties properties
, char *preferred
, char *fallback
)
31 int value
= mlt_properties_get_int( properties
, preferred
);
33 value
= mlt_properties_get_int( properties
, fallback
);
40 static int filter_get_image( mlt_frame
this, uint8_t **image
, mlt_image_format
*format
, int *width
, int *height
, int writable
)
44 // Get the properties from the frame
45 mlt_properties properties
= mlt_frame_properties( this );
47 // Assign requested width/height from our subordinate
49 int oheight
= *height
;
52 char *rescale
= mlt_properties_get( properties
, "rescale.interp" );
53 if ( rescale
!= NULL
&& !strcmp( rescale
, "none" ) )
54 return mlt_frame_get_image( this, image
, format
, width
, height
, writable
);
56 if ( mlt_properties_get( properties
, "distort" ) == NULL
)
58 // Normalise the input and out display aspect
59 int normalised_width
= mlt_properties_get_int( properties
, "normalised_width" );
60 int normalised_height
= mlt_properties_get_int( properties
, "normalised_height" );
61 double input_ar
= mlt_frame_get_aspect_ratio( this );
62 double output_ar
= mlt_properties_get_double( properties
, "consumer_aspect_ratio" );
64 // Optimised for the input_ar > output_ar case (e.g. widescreen on standard)
65 int scaled_width
= normalised_width
;
66 int scaled_height
= output_ar
/ input_ar
* normalised_height
;
68 // Now ensure that our images fit in the normalised frame
69 if ( scaled_height
> normalised_height
)
71 scaled_width
= input_ar
/ output_ar
* normalised_width
;
72 scaled_height
= normalised_height
;
75 // Now calculate the actual image size that we want
76 owidth
= scaled_width
* owidth
/ normalised_width
;
77 oheight
= scaled_height
* oheight
/ normalised_height
;
79 // Tell frame we have conformed the aspect to the consumer
80 mlt_frame_set_aspect_ratio( this, output_ar
);
83 // Now pass on the calculations down the line
84 mlt_properties_set_int( properties
, "resize_width", *width
);
85 mlt_properties_set_int( properties
, "resize_height", *height
);
88 error
= mlt_frame_get_image( this, image
, format
, &owidth
, &oheight
, writable
);
90 // We only know how to process yuv422 at the moment
91 if ( error
== 0 && *format
== mlt_image_yuv422
)
93 // Correct field order if needed
94 if ( mlt_properties_get_int( properties
, "top_field_first" ) == 1 )
96 // Get the input image, width and height
98 uint8_t *image
= mlt_properties_get_data( properties
, "image", &size
);
100 // Keep the original image around to be destroyed on frame close
101 mlt_properties_rename( properties
, "image", "original_image" );
103 // Offset the image pointer by one line
107 // Set the new image pointer with no destructor
108 mlt_properties_set_data( properties
, "image", image
, size
, NULL
, NULL
);
110 // Set the normalised field order
111 mlt_properties_set_int( properties
, "top_field_first", 0 );
114 if ( !strcmp( mlt_properties_get( properties
, "resize.scale" ), "affine" ) )
116 *image
= mlt_frame_rescale_yuv422( this, *width
, *height
);
118 else if ( strcmp( mlt_properties_get( properties
, "resize.scale" ), "none" ) != 0 )
120 *image
= mlt_frame_resize_yuv422( this, *width
, *height
);
132 /** Filter processing.
135 static mlt_frame
filter_process( mlt_filter
this, mlt_frame frame
)
137 mlt_frame_push_get_image( frame
, filter_get_image
);
138 mlt_properties_set( mlt_frame_properties( frame
), "resize.scale", mlt_properties_get( mlt_filter_properties( this ), "scale" ) );
142 /** Constructor for the filter.
145 mlt_filter
filter_resize_init( char *arg
)
147 mlt_filter
this = calloc( sizeof( struct mlt_filter_s
), 1 );
148 if ( mlt_filter_init( this, this ) == 0 )
150 this->process
= filter_process
;
152 mlt_properties_set( mlt_filter_properties( this ), "scale", arg
);
154 mlt_properties_set( mlt_filter_properties( this ), "scale", "off" );