/*

 * LIBOIL - Library of Optimized Inner Loops

 * Copyright (c) 2003,2004 David A. Schleef <ds@schleef.org>

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,

 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 */

//Portions Copyright (c)  2008-2009 Nokia Corporation and/or its subsidiary(-ies). All rights reserved. 

#ifdef HAVE_CONFIG_H

#include "config.h"

#endif

#include <liboil/liboilfunction.h>

#include "liboil/dct/dct.h"

#include <math.h>

/**

 * oil_idct8_f64:

 * @d_8:

 * @dstr:

 * @s_8:

 * @sstr:

 *

 * Performs a Inverse Discrete Cosine Transform on @s_8 and places

 * the result in @d_8.

 */

OIL_DEFINE_CLASS (idct8_f64, "double *d_8, int dstr, double *s_8, int sstr");

#define C0_9808 0.980785280

#define C0_9239 0.923879532

#define C0_8315 0.831469612

#define C0_7071 0.707106781

#define C0_5556 0.555570233

#define C0_3827 0.382683432

#define C0_1951 0.195090322

static void idct8_f64_ref(double *dest, int dstr, const double *src, int sstr)

{

	static double idct_coeff[8][8];

	static int idct_coeff_init = 0;

	int i,j;

	double x;

	if(!idct_coeff_init){

		double scale;

		for(i=0;i<8;i++){

			scale = (i==0) ? sqrt(0.125) : 0.5;

			for(j=0;j<8;j++){

				idct_coeff[j][i] = scale *

					cos((M_PI/8)*i*(j+0.5));

			}

		}

		idct_coeff_init = 1;

	}

	for(i=0;i<8;i++){

		x = 0;

		for(j=0;j<8;j++){

			x += idct_coeff[i][j] * OIL_GET (src, sstr*j, double);

		}

		OIL_GET (dest, dstr*i, double) = x;

	}

}

OIL_DEFINE_IMPL_REF (idct8_f64_ref, idct8_f64);

static void idct8_f64_fastx(double *dest, int dstr, const double *src, int sstr)

{

	double s07, s16, s25, s34;

	double d07, d16, d25, d34;

	double ss07s34, ss16s25;

	double ds07s34, ds16s25;

	ss07s34 = C0_7071*(OIL_GET(src,sstr*0, double) + OIL_GET(src,sstr*4, double));

	ss16s25 = C0_7071*(OIL_GET(src,sstr*0, double) - OIL_GET(src,sstr*4, double));

	ds07s34 = C0_9239* OIL_GET(src,sstr*2, double) + C0_3827* OIL_GET(src,sstr*6, double);

	ds16s25 = C0_3827* OIL_GET(src,sstr*2, double) - C0_9239* OIL_GET(src,sstr*6, double);

	s07 = ss07s34 + ds07s34;

	s34 = ss07s34 - ds07s34;

	s16 = ss16s25 + ds16s25;

	s25 = ss16s25 - ds16s25;

	d07 = C0_9808* OIL_GET(src,sstr*1, double) + C0_8315* OIL_GET(src,sstr*3, double)

		+ C0_5556* OIL_GET(src,sstr*5, double) + C0_1951* OIL_GET(src,sstr*7, double);

	d16 = C0_8315* OIL_GET(src,sstr*1, double) - C0_1951* OIL_GET(src,sstr*3, double)

		- C0_9808* OIL_GET(src,sstr*5, double) - C0_5556* OIL_GET(src,sstr*7, double);

	d25 = C0_5556* OIL_GET(src,sstr*1, double) - C0_9808* OIL_GET(src,sstr*3, double)

		+ C0_1951* OIL_GET(src,sstr*5, double) + C0_8315* OIL_GET(src,sstr*7, double);

	d34 = C0_1951* OIL_GET(src,sstr*1, double) - C0_5556* OIL_GET(src,sstr*3, double)

		+ C0_8315* OIL_GET(src,sstr*5, double) - C0_9808* OIL_GET(src,sstr*7, double);

	OIL_GET(dest,dstr*0, double) = 0.5 * (s07 + d07);

	OIL_GET(dest,dstr*1, double) = 0.5 * (s16 + d16);

	OIL_GET(dest,dstr*2, double) = 0.5 * (s25 + d25);

	OIL_GET(dest,dstr*3, double) = 0.5 * (s34 + d34);

	OIL_GET(dest,dstr*4, double) = 0.5 * (s34 - d34);

	OIL_GET(dest,dstr*5, double) = 0.5 * (s25 - d25);

	OIL_GET(dest,dstr*6, double) = 0.5 * (s16 - d16);

	OIL_GET(dest,dstr*7, double) = 0.5 * (s07 - d07);

}

OIL_DEFINE_IMPL (idct8_f64_fastx, idct8_f64);

#ifdef	__SYMBIAN32__

OilFunctionClass* __oil_function_class_idct8_f64() {

		return &_oil_function_class_idct8_f64;

}

#endif

#ifdef	__SYMBIAN32__

OilFunctionImpl* __oil_function_impl_idct8_f64_ref() {

		return &_oil_function_impl_idct8_f64_ref;

}

#endif

#ifdef	__SYMBIAN32__

OilFunctionImpl* __oil_function_impl_idct8_f64_fastx() {

		return &_oil_function_impl_idct8_f64_fastx;

}

#endif

#ifdef	__SYMBIAN32__

EXPORT_C void** _oil_function_class_ptr_idct8_f64 ()	{

	oil_function_class_ptr_idct8_f64 = __oil_function_class_idct8_f64();

	return &oil_function_class_ptr_idct8_f64->func;

	}

#endif