ref: 46ab54abf8c4481017e9efa7f0ff84045f984526
dir: /vp8/encoder/dct.c/
/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <math.h>
#include "vpx_ports/config.h"
#if CONFIG_T8X8
void vp8_short_fdct8x8_c(short *block, short *coefs, int pitch)
{
int j1, i, j, k;
float b[8];
float b1[8];
float d[8][8];
float f0 = (float) .7071068;
float f1 = (float) .4903926;
float f2 = (float) .4619398;
float f3 = (float) .4157348;
float f4 = (float) .3535534;
float f5 = (float) .2777851;
float f6 = (float) .1913417;
float f7 = (float) .0975452;
pitch = pitch / 2;
for (i = 0, k = 0; i < 8; i++, k += pitch)
{
for (j = 0; j < 8; j++)
{
b[j] = (float)( block[k + j]<<3);
}
/* Horizontal transform */
for (j = 0; j < 4; j++)
{
j1 = 7 - j;
b1[j] = b[j] + b[j1];
b1[j1] = b[j] - b[j1];
}
b[0] = b1[0] + b1[3];
b[1] = b1[1] + b1[2];
b[2] = b1[1] - b1[2];
b[3] = b1[0] - b1[3];
b[4] = b1[4];
b[5] = (b1[6] - b1[5]) * f0;
b[6] = (b1[6] + b1[5]) * f0;
b[7] = b1[7];
d[i][0] = (b[0] + b[1]) * f4;
d[i][4] = (b[0] - b[1]) * f4;
d[i][2] = b[2] * f6 + b[3] * f2;
d[i][6] = b[3] * f6 - b[2] * f2;
b1[4] = b[4] + b[5];
b1[7] = b[7] + b[6];
b1[5] = b[4] - b[5];
b1[6] = b[7] - b[6];
d[i][1] = b1[4] * f7 + b1[7] * f1;
d[i][5] = b1[5] * f3 + b1[6] * f5;
d[i][7] = b1[7] * f7 - b1[4] * f1;
d[i][3] = b1[6] * f3 - b1[5] * f5;
}
/* Vertical transform */
for (i = 0; i < 8; i++)
{
for (j = 0; j < 4; j++)
{
j1 = 7 - j;
b1[j] = d[j][i] + d[j1][i];
b1[j1] = d[j][i] - d[j1][i];
}
b[0] = b1[0] + b1[3];
b[1] = b1[1] + b1[2];
b[2] = b1[1] - b1[2];
b[3] = b1[0] - b1[3];
b[4] = b1[4];
b[5] = (b1[6] - b1[5]) * f0;
b[6] = (b1[6] + b1[5]) * f0;
b[7] = b1[7];
d[0][i] = (b[0] + b[1]) * f4;
d[4][i] = (b[0] - b[1]) * f4;
d[2][i] = b[2] * f6 + b[3] * f2;
d[6][i] = b[3] * f6 - b[2] * f2;
b1[4] = b[4] + b[5];
b1[7] = b[7] + b[6];
b1[5] = b[4] - b[5];
b1[6] = b[7] - b[6];
d[1][i] = b1[4] * f7 + b1[7] * f1;
d[5][i] = b1[5] * f3 + b1[6] * f5;
d[7][i] = b1[7] * f7 - b1[4] * f1;
d[3][i] = b1[6] * f3 - b1[5] * f5;
}
for (i = 0; i < 8; i++)
{
for (j = 0; j < 8; j++)
{
*(coefs + j + i * 8) = (short) floor(d[i][j] +0.5);
}
}
return;
}
void vp8_short_fhaar2x2_c(short *input, short *output, int pitch) //pitch = 8
{
/* [1 1 ; 1 -1] orthogonal transform */
/* use position: 0,1, 4, 8 */
int i;
short *ip1 = input;
short *op1 = output;
for (i = 0; i < 16; i++)
{
op1[i] = 0;
}
op1[0]=(ip1[0] + ip1[1] + ip1[4] + ip1[8] + 1)>>1;
op1[1]=(ip1[0] - ip1[1] + ip1[4] - ip1[8])>>1;
op1[4]=(ip1[0] + ip1[1] - ip1[4] - ip1[8])>>1;
op1[8]=(ip1[0] - ip1[1] - ip1[4] + ip1[8])>>1;
}
#endif
void vp8_short_fdct4x4_c(short *input, short *output, int pitch)
{
int i;
int a1, b1, c1, d1;
short *ip = input;
short *op = output;
for (i = 0; i < 4; i++)
{
a1 = ((ip[0] + ip[3])<<5);
b1 = ((ip[1] + ip[2])<<5);
c1 = ((ip[1] - ip[2])<<5);
d1 = ((ip[0] - ip[3])<<5);
op[0] = a1 + b1;
op[2] = a1 - b1;
op[1] = (c1 * 2217 + d1 * 5352 + 14500)>>12;
op[3] = (d1 * 2217 - c1 * 5352 + 7500)>>12;
ip += pitch / 2;
op += 4;
}
ip = output;
op = output;
for (i = 0; i < 4; i++)
{
a1 = ip[0] + ip[12];
b1 = ip[4] + ip[8];
c1 = ip[4] - ip[8];
d1 = ip[0] - ip[12];
op[0] = ( a1 + b1 + 7)>>4;
op[8] = ( a1 - b1 + 7)>>4;
op[4] =((c1 * 2217 + d1 * 5352 + 12000)>>16) + (d1!=0);
op[12] = (d1 * 2217 - c1 * 5352 + 51000)>>16;
ip++;
op++;
}
}
void vp8_short_fdct8x4_c(short *input, short *output, int pitch)
{
vp8_short_fdct4x4_c(input, output, pitch);
vp8_short_fdct4x4_c(input + 4, output + 16, pitch);
}
void vp8_short_walsh4x4_c(short *input, short *output, int pitch)
{
int i;
int a1, b1, c1, d1;
int a2, b2, c2, d2;
short *ip = input;
short *op = output;
for (i = 0; i < 4; i++)
{
a1 = ((ip[0] + ip[2]));
d1 = ((ip[1] + ip[3]));
c1 = ((ip[1] - ip[3]));
b1 = ((ip[0] - ip[2]));
op[0] = a1 + d1;
op[1] = b1 + c1;
op[2] = b1 - c1;
op[3] = a1 - d1;
ip += pitch / 2;
op += 4;
}
ip = output;
op = output;
for (i = 0; i < 4; i++)
{
a1 = ip[0] + ip[8];
d1 = ip[4] + ip[12];
c1 = ip[4] - ip[12];
b1 = ip[0] - ip[8];
a2 = a1 + d1;
b2 = b1 + c1;
c2 = b1 - c1;
d2 = a1 - d1;
a2 += a2<0;
b2 += b2<0;
c2 += c2<0;
d2 += d2<0;
op[0] = (a2+1) >> 2;
op[4] = (b2+1) >> 2;
op[8] = (c2+1) >> 2;
op[12]= (d2+1) >> 2;
ip++;
op++;
}
}