2 * filter_resize.c -- resizing filter
3 * Copyright (C) 2003-2004 Ushodaya Enterprises Limited
4 * Author: Charles Yates <charles.yates@pandora.be>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * This library 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 GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include "filter_resize.h"
23 #include <framework/mlt_frame.h>
33 static inline void swap_bytes( uint8_t *upper
, uint8_t *lower
)
43 static int filter_get_image( mlt_frame
this, uint8_t **image
, mlt_image_format
*format
, int *width
, int *height
, int writable
)
47 // Get the properties from the frame
48 mlt_properties properties
= MLT_FRAME_PROPERTIES( this );
50 // Pop the top of stack now
51 mlt_filter filter
= mlt_frame_pop_service( this );
53 // Retrieve the aspect ratio
54 double aspect_ratio
= mlt_deque_pop_back_double( MLT_FRAME_IMAGE_STACK( this ) );
56 // Assign requested width/height from our subordinate
58 int oheight
= *height
;
60 // Check for the special case - no aspect ratio means no problem :-)
61 if ( aspect_ratio
== 0.0 )
62 aspect_ratio
= mlt_properties_get_double( properties
, "consumer_aspect_ratio" );
64 // Reset the aspect ratio
65 mlt_properties_set_double( properties
, "aspect_ratio", aspect_ratio
);
68 char *rescale
= mlt_properties_get( properties
, "rescale.interp" );
69 if ( rescale
!= NULL
&& !strcmp( rescale
, "none" ) )
70 return mlt_frame_get_image( this, image
, format
, width
, height
, writable
);
72 if ( mlt_properties_get_int( properties
, "distort" ) == 0 )
74 // Normalise the input and out display aspect
75 int normalised_width
= mlt_properties_get_int( properties
, "normalised_width" );
76 int normalised_height
= mlt_properties_get_int( properties
, "normalised_height" );
77 int real_width
= mlt_properties_get_int( properties
, "real_width" );
78 int real_height
= mlt_properties_get_int( properties
, "real_height" );
79 if ( real_width
== 0 )
80 real_width
= mlt_properties_get_int( properties
, "width" );
81 if ( real_height
== 0 )
82 real_height
= mlt_properties_get_int( properties
, "height" );
83 double input_ar
= aspect_ratio
* real_width
/ real_height
;
84 double output_ar
= mlt_properties_get_double( properties
, "consumer_aspect_ratio" ) * owidth
/ oheight
;
86 //fprintf( stderr, "normalised %dx%d output %dx%d %f %f\n", normalised_width, normalised_height, owidth, oheight, ( float )output_ar, ( float )mlt_properties_get_double( properties, "consumer_aspect_ratio" ) * owidth / oheight );
88 // Optimised for the input_ar > output_ar case (e.g. widescreen on standard)
89 int scaled_width
= rint( 0.5 + ( input_ar
* normalised_width
) / output_ar
);
90 int scaled_height
= normalised_height
;
92 // Now ensure that our images fit in the output frame
93 if ( scaled_width
> normalised_width
)
95 scaled_width
= normalised_width
;
96 scaled_height
= rint( 0.5 + ( output_ar
* normalised_height
) / input_ar
);
99 // Now calculate the actual image size that we want
100 owidth
= rint( 0.5 + scaled_width
* owidth
/ normalised_width
);
101 oheight
= rint( 0.5 + scaled_height
* oheight
/ normalised_height
);
103 // Tell frame we have conformed the aspect to the consumer
104 mlt_frame_set_aspect_ratio( this, mlt_properties_get_double( properties
, "consumer_aspect_ratio" ) );
107 mlt_properties_set_int( properties
, "distort", 0 );
109 // Now pass on the calculations down the line
110 mlt_properties_set_int( properties
, "resize_width", *width
);
111 mlt_properties_set_int( properties
, "resize_height", *height
);
114 error
= mlt_frame_get_image( this, image
, format
, &owidth
, &oheight
, writable
);
116 // We only know how to process yuv422 at the moment
117 if ( error
== 0 && *format
== mlt_image_yuv422
&& *image
!= NULL
)
119 // Get the requested scale operation
120 char *op
= mlt_properties_get( MLT_FILTER_PROPERTIES( filter
), "scale" );
122 // Provides a manual override for misreported field order
123 if ( mlt_properties_get( properties
, "meta.top_field_first" ) )
124 mlt_properties_set( properties
, "top_field_first", mlt_properties_get_int( properties
, "meta.top_field_first" ) );
126 // Correct field order if needed
127 if ( mlt_properties_get_int( properties
, "top_field_first" ) == 1 )
129 // Get the input image, width and height
131 uint8_t *image
= mlt_properties_get_data( properties
, "image", &size
);
132 uint8_t *ptr
= image
+ owidth
* 2;
136 // Swap the lines around
142 swap_bytes( image
++, ptr
++ );
143 swap_bytes( image
++, ptr
++ );
149 // Set the normalised field order
150 mlt_properties_set_int( properties
, "top_field_first", 0 );
151 mlt_properties_set_int( properties
, "meta.top_field_first", 0 );
154 if ( !strcmp( op
, "affine" ) )
156 *image
= mlt_frame_rescale_yuv422( this, *width
, *height
);
158 else if ( strcmp( op
, "none" ) != 0 )
160 *image
= mlt_frame_resize_yuv422( this, *width
, *height
);
172 /** Filter processing.
175 static mlt_frame
filter_process( mlt_filter
this, mlt_frame frame
)
177 // Store the aspect ratio reported by the source
178 mlt_deque_push_back_double( MLT_FRAME_IMAGE_STACK( frame
), mlt_frame_get_aspect_ratio( frame
) );
180 // Push this on to the service stack
181 mlt_frame_push_service( frame
, this );
183 // Push the get_image method on to the stack
184 mlt_frame_push_get_image( frame
, filter_get_image
);
189 /** Constructor for the filter.
192 mlt_filter
filter_resize_init( char *arg
)
194 mlt_filter
this = calloc( sizeof( struct mlt_filter_s
), 1 );
195 if ( mlt_filter_init( this, this ) == 0 )
197 this->process
= filter_process
;
198 mlt_properties_set( MLT_FILTER_PROPERTIES( this ), "scale", arg
== NULL ?
"off" : arg
);