/* im_LCh2Lab
 *
 * 15/11/94 JC
 *	- error messages added
 *	- memory leak fixed
 * 16/11/94 JC
 *	- uses im_wrap_oneonebuf() now
 * 8/2/95 JC
 *	- im_wrap v2
 * 2/11/09
 * 	- gtkdoc
 */

/*

    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  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 <vips/intl.h>

#include <stdio.h>
#include <math.h>

#include <vips/vips.h>
#include <vips/internal.h>

#ifdef WITH_DMALLOC
#include <dmalloc.h>
#endif /*WITH_DMALLOC*/

/* Process a buffer of data.
 */
void
imb_LCh2Lab( float *p, float *q, int n )
{		
	int x;

	for( x = 0; x < n; x++ ) {
		float L = p[0];
		float C = p[1];
		float h = p[2];
		float a, b;

		p += 3;

		a = C * cos( IM_RAD( h ) );
		b = C * sin( IM_RAD( h ) );

		q[0] = L;
		q[1] = a;
		q[2] = b;
		q += 3;
	}
}

/**
 * im_LCh2Lab:
 * @in: input image
 * @out: output image
 *
 * Turn LCh to Lab.
 *
 * Returns: 0 on success, -1 on error.
 */
int 
im_LCh2Lab( IMAGE *in, IMAGE *out )
{	
	return( im__colour_unary( "im_LCh2Lab", in, out, IM_TYPE_LAB,
		(im_wrapone_fn) imb_LCh2Lab, NULL, NULL ) );
}
