libvips/libvips/colour/Lab2LabS.c

125 lines
2.9 KiB
C

/* Lab2LabS: quantise FLOAT Lab image into signed short format
*
* 12/12/02 JC
* - from im_Lab2LabS
* 1/11/09
* - gtkdoc
* - cleanups
* 20/9/12
* - redo as a class
*/
/*
This file is part of VIPS.
VIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA
*/
/*
These files are distributed with VIPS - http://www.vips.ecs.soton.ac.uk
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif /*HAVE_CONFIG_H*/
#include <glib/gi18n-lib.h>
#include <stdio.h>
#include <math.h>
#include <vips/vips.h>
#include "pcolour.h"
typedef VipsColourCode VipsLab2LabS;
typedef VipsColourCodeClass VipsLab2LabSClass;
G_DEFINE_TYPE( VipsLab2LabS, vips_Lab2LabS, VIPS_TYPE_COLOUR_CODE );
static void
vips_Lab2LabS_line( VipsColour *colour, VipsPel *out, VipsPel **in, int width )
{
float * restrict p = (float *) in[0];
signed short * restrict q = (signed short *) out;
int i;
for( i = 0; i < width; i++ ) {
q[0] = p[0] * (32767.0 / 100.0);
q[1] = p[1] * (32768.0 / 128.0);
q[2] = p[2] * (32768.0 / 128.0);
q += 3;
p += 3;
}
}
static void
vips_Lab2LabS_class_init( VipsLab2LabSClass *class )
{
VipsObjectClass *object_class = (VipsObjectClass *) class;
VipsColourClass *colour_class = VIPS_COLOUR_CLASS( class );
object_class->nickname = "Lab2LabS";
object_class->description = _( "transform float Lab to signed short" );
colour_class->process_line = vips_Lab2LabS_line;
}
static void
vips_Lab2LabS_init( VipsLab2LabS *Lab2LabS )
{
VipsColour *colour = VIPS_COLOUR( Lab2LabS );
VipsColourCode *code = VIPS_COLOUR_CODE( Lab2LabS );
colour->interpretation = VIPS_INTERPRETATION_LABS;
colour->format = VIPS_FORMAT_SHORT;
colour->input_bands = 3;
colour->bands = 3;
code->input_coding = VIPS_CODING_NONE;
code->input_format = VIPS_FORMAT_FLOAT;
}
/**
* vips_Lab2LabS: (method)
* @in: input image
* @out: (out): output image
* @...: %NULL-terminated list of optional named arguments
*
* Turn Lab to LabS, signed 16-bit int fixed point.
*
* See also: vips_LabQ2Lab().
*
* Returns: 0 on success, -1 on error.
*/
int
vips_Lab2LabS( VipsImage *in, VipsImage **out, ... )
{
va_list ap;
int result;
va_start( ap, out );
result = vips_call_split( "Lab2LabS", ap, in, out );
va_end( ap );
return( result );
}