/*

 * Floating point AAN DCT

 * this implementation is based upon the IJG integer AAN DCT (see jfdctfst.c)

 *

 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>

 * Copyright (c) 2003 Roman Shaposhnik

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

/**

 * @file

 * @brief

 *     Floating point AAN DCT

 * @author Michael Niedermayer <michaelni@gmx.at>

 */

#include "faandct.h"

#include "libavutil/emms.h"

#include "libavutil/internal.h"

#include "libavutil/libm.h"

typedef float FLOAT;

/* numbers generated by arbitrary precision arithmetic followed by truncation

to 36 fractional digits (enough for a 128-bit IEEE quad, see /usr/include/math.h

for this approach). Unfortunately, long double is not always available correctly,

e.g ppc has issues.

TODO: add L suffixes when ppc and toolchains sort out their stuff.

*/

#define B0 1.000000000000000000000000000000000000

#define B1 0.720959822006947913789091890943021267 // (cos(pi*1/16)sqrt(2))^-1

#define B2 0.765366864730179543456919968060797734 // (cos(pi*2/16)sqrt(2))^-1

#define B3 0.850430094767256448766702844371412325 // (cos(pi*3/16)sqrt(2))^-1

#define B4 1.000000000000000000000000000000000000 // (cos(pi*4/16)sqrt(2))^-1

#define B5 1.272758580572833938461007018281767032 // (cos(pi*5/16)sqrt(2))^-1

#define B6 1.847759065022573512256366378793576574 // (cos(pi*6/16)sqrt(2))^-1

#define B7 3.624509785411551372409941227504289587 // (cos(pi*7/16)sqrt(2))^-1

#define A1 M_SQRT1_2              // cos(pi*4/16)

#define A2 0.54119610014619698435 // cos(pi*6/16)sqrt(2)

#define A5 0.38268343236508977170 // cos(pi*6/16)

#define A4 1.30656296487637652774 // cos(pi*2/16)sqrt(2)

static const FLOAT postscale[64]={

B0*B0, B0*B1, B0*B2, B0*B3, B0*B4, B0*B5, B0*B6, B0*B7,

B1*B0, B1*B1, B1*B2, B1*B3, B1*B4, B1*B5, B1*B6, B1*B7,

B2*B0, B2*B1, B2*B2, B2*B3, B2*B4, B2*B5, B2*B6, B2*B7,

B3*B0, B3*B1, B3*B2, B3*B3, B3*B4, B3*B5, B3*B6, B3*B7,

B4*B0, B4*B1, B4*B2, B4*B3, B4*B4, B4*B5, B4*B6, B4*B7,

B5*B0, B5*B1, B5*B2, B5*B3, B5*B4, B5*B5, B5*B6, B5*B7,

B6*B0, B6*B1, B6*B2, B6*B3, B6*B4, B6*B5, B6*B6, B6*B7,

B7*B0, B7*B1, B7*B2, B7*B3, B7*B4, B7*B5, B7*B6, B7*B7,

};

static av_always_inline void row_fdct(FLOAT temp[64], int16_t *data)

{

    FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

    FLOAT tmp10, tmp11, tmp12, tmp13;

    FLOAT z2, z4, z11, z13;

    int i;

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

        tmp0= data[0 + i] + data[7 + i];

        tmp7= data[0 + i] - data[7 + i];

        tmp1= data[1 + i] + data[6 + i];

        tmp6= data[1 + i] - data[6 + i];

        tmp2= data[2 + i] + data[5 + i];

        tmp5= data[2 + i] - data[5 + i];

        tmp3= data[3 + i] + data[4 + i];

        tmp4= data[3 + i] - data[4 + i];

        tmp10= tmp0 + tmp3;

        tmp13= tmp0 - tmp3;

        tmp11= tmp1 + tmp2;

        tmp12= tmp1 - tmp2;

        temp[0 + i]= tmp10 + tmp11;

        temp[4 + i]= tmp10 - tmp11;

        tmp12 += tmp13;

        tmp12 *= A1;

        temp[2 + i]= tmp13 + tmp12;

        temp[6 + i]= tmp13 - tmp12;

        tmp4 += tmp5;

        tmp5 += tmp6;

        tmp6 += tmp7;

        z2= tmp4*(A2+A5) - tmp6*A5;

        z4= tmp6*(A4-A5) + tmp4*A5;

        tmp5*=A1;

        z11= tmp7 + tmp5;

        z13= tmp7 - tmp5;

        temp[5 + i]= z13 + z2;

        temp[3 + i]= z13 - z2;

        temp[1 + i]= z11 + z4;

        temp[7 + i]= z11 - z4;

    }

}

void ff_faandct(int16_t *data)

{

    FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

    FLOAT tmp10, tmp11, tmp12, tmp13;

    FLOAT z2, z4, z11, z13;

    FLOAT temp[64];

    int i;

    emms_c();

    row_fdct(temp, data);

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

        tmp0= temp[8*0 + i] + temp[8*7 + i];

        tmp7= temp[8*0 + i] - temp[8*7 + i];

        tmp1= temp[8*1 + i] + temp[8*6 + i];

        tmp6= temp[8*1 + i] - temp[8*6 + i];

        tmp2= temp[8*2 + i] + temp[8*5 + i];

        tmp5= temp[8*2 + i] - temp[8*5 + i];

        tmp3= temp[8*3 + i] + temp[8*4 + i];

        tmp4= temp[8*3 + i] - temp[8*4 + i];

        tmp10= tmp0 + tmp3;

        tmp13= tmp0 - tmp3;

        tmp11= tmp1 + tmp2;

        tmp12= tmp1 - tmp2;

        data[8*0 + i]= lrintf(postscale[8*0 + i] * (tmp10 + tmp11));

        data[8*4 + i]= lrintf(postscale[8*4 + i] * (tmp10 - tmp11));

        tmp12 += tmp13;

        tmp12 *= A1;

        data[8*2 + i]= lrintf(postscale[8*2 + i] * (tmp13 + tmp12));

        data[8*6 + i]= lrintf(postscale[8*6 + i] * (tmp13 - tmp12));

        tmp4 += tmp5;

        tmp5 += tmp6;

        tmp6 += tmp7;

        z2= tmp4*(A2+A5) - tmp6*A5;

        z4= tmp6*(A4-A5) + tmp4*A5;

        tmp5*=A1;

        z11= tmp7 + tmp5;

        z13= tmp7 - tmp5;

        data[8*5 + i]= lrintf(postscale[8*5 + i] * (z13 + z2));

        data[8*3 + i]= lrintf(postscale[8*3 + i] * (z13 - z2));

        data[8*1 + i]= lrintf(postscale[8*1 + i] * (z11 + z4));

        data[8*7 + i]= lrintf(postscale[8*7 + i] * (z11 - z4));

    }

}

void ff_faandct248(int16_t *data)

{

    FLOAT tmp0, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7;

    FLOAT tmp10, tmp11, tmp12, tmp13;

    FLOAT temp[64];

    int i;

    emms_c();

    row_fdct(temp, data);

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

        tmp0 = temp[8*0 + i] + temp[8*1 + i];

        tmp1 = temp[8*2 + i] + temp[8*3 + i];

        tmp2 = temp[8*4 + i] + temp[8*5 + i];

        tmp3 = temp[8*6 + i] + temp[8*7 + i];

        tmp4 = temp[8*0 + i] - temp[8*1 + i];

        tmp5 = temp[8*2 + i] - temp[8*3 + i];

        tmp6 = temp[8*4 + i] - temp[8*5 + i];

        tmp7 = temp[8*6 + i] - temp[8*7 + i];

        tmp10 = tmp0 + tmp3;

        tmp11 = tmp1 + tmp2;

        tmp12 = tmp1 - tmp2;

        tmp13 = tmp0 - tmp3;

        data[8*0 + i] = lrintf(postscale[8*0 + i] * (tmp10 + tmp11));

        data[8*4 + i] = lrintf(postscale[8*4 + i] * (tmp10 - tmp11));

        tmp12 += tmp13;

        tmp12 *= A1;

        data[8*2 + i] = lrintf(postscale[8*2 + i] * (tmp13 + tmp12));

        data[8*6 + i] = lrintf(postscale[8*6 + i] * (tmp13 - tmp12));

        tmp10 = tmp4 + tmp7;

        tmp11 = tmp5 + tmp6;

        tmp12 = tmp5 - tmp6;

        tmp13 = tmp4 - tmp7;

        data[8*1 + i] = lrintf(postscale[8*0 + i] * (tmp10 + tmp11));

        data[8*5 + i] = lrintf(postscale[8*4 + i] * (tmp10 - tmp11));

        tmp12 += tmp13;

        tmp12 *= A1;

        data[8*3 + i] = lrintf(postscale[8*2 + i] * (tmp13 + tmp12));

        data[8*7 + i] = lrintf(postscale[8*6 + i] * (tmp13 - tmp12));

    }

}