ref: 6fd0929fb53ca5dee83ff99f34d987a88eefa1ea
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"
#include "vp8/common/idct.h"
static const int xC1S7 = 16069;
static const int xC2S6 = 15137;
static const int xC3S5 = 13623;
static const int xC4S4 = 11585;
static const int xC5S3 = 9102;
static const int xC6S2 = 6270;
static const int xC7S1 = 3196;
#define SHIFT_BITS 14
#define DOROUND(X) X += (1<<(SHIFT_BITS-1));
#define FINAL_SHIFT 3
#define FINAL_ROUNDING (1<<(FINAL_SHIFT -1))
#define IN_SHIFT (FINAL_SHIFT+1)
void vp8_short_fdct8x8_c(short *InputData, short *OutputData, int pitch) {
int loop;
int short_pitch = pitch >> 1;
int is07, is12, is34, is56;
int is0734, is1256;
int id07, id12, id34, id56;
int irot_input_x, irot_input_y;
int icommon_product1; // Re-used product (c4s4 * (s12 - s56))
int icommon_product2; // Re-used product (c4s4 * (d12 + d56))
int temp1, temp2; // intermediate variable for computation
int InterData[64];
int *ip = InterData;
short *op = OutputData;
for (loop = 0; loop < 8; loop++) {
// Pre calculate some common sums and differences.
is07 = (InputData[0] + InputData[7]) << IN_SHIFT;
is12 = (InputData[1] + InputData[2]) << IN_SHIFT;
is34 = (InputData[3] + InputData[4]) << IN_SHIFT;
is56 = (InputData[5] + InputData[6]) << IN_SHIFT;
id07 = (InputData[0] - InputData[7]) << IN_SHIFT;
id12 = (InputData[1] - InputData[2]) << IN_SHIFT;
id34 = (InputData[3] - InputData[4]) << IN_SHIFT;
id56 = (InputData[5] - InputData[6]) << IN_SHIFT;
is0734 = is07 + is34;
is1256 = is12 + is56;
// Pre-Calculate some common product terms.
icommon_product1 = xC4S4 * (is12 - is56);
DOROUND(icommon_product1)
icommon_product1 >>= SHIFT_BITS;
icommon_product2 = xC4S4 * (id12 + id56);
DOROUND(icommon_product2)
icommon_product2 >>= SHIFT_BITS;
ip[0] = (xC4S4 * (is0734 + is1256));
DOROUND(ip[0]);
ip[0] >>= SHIFT_BITS;
ip[4] = (xC4S4 * (is0734 - is1256));
DOROUND(ip[4]);
ip[4] >>= SHIFT_BITS;
// Define inputs to rotation for outputs 2 and 6
irot_input_x = id12 - id56;
irot_input_y = is07 - is34;
// Apply rotation for outputs 2 and 6.
temp1 = xC6S2 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC2S6 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[2] = temp1 + temp2;
temp1 = xC6S2 * irot_input_y;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC2S6 * irot_input_x;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[6] = temp1 - temp2;
// Define inputs to rotation for outputs 1 and 7
irot_input_x = icommon_product1 + id07;
irot_input_y = -(id34 + icommon_product2);
// Apply rotation for outputs 1 and 7.
temp1 = xC1S7 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC7S1 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[1] = temp1 - temp2;
temp1 = xC7S1 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC1S7 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[7] = temp1 + temp2;
// Define inputs to rotation for outputs 3 and 5
irot_input_x = id07 - icommon_product1;
irot_input_y = id34 - icommon_product2;
// Apply rotation for outputs 3 and 5.
temp1 = xC3S5 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC5S3 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[3] = temp1 - temp2;
temp1 = xC5S3 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC3S5 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
ip[5] = temp1 + temp2;
// Increment data pointer for next row
InputData += short_pitch;
ip += 8;
}
// Performed DCT on rows, now transform the columns
ip = InterData;
for (loop = 0; loop < 8; loop++) {
// Pre calculate some common sums and differences.
is07 = ip[0 * 8] + ip[7 * 8];
is12 = ip[1 * 8] + ip[2 * 8];
is34 = ip[3 * 8] + ip[4 * 8];
is56 = ip[5 * 8] + ip[6 * 8];
id07 = ip[0 * 8] - ip[7 * 8];
id12 = ip[1 * 8] - ip[2 * 8];
id34 = ip[3 * 8] - ip[4 * 8];
id56 = ip[5 * 8] - ip[6 * 8];
is0734 = is07 + is34;
is1256 = is12 + is56;
// Pre-Calculate some common product terms
icommon_product1 = xC4S4 * (is12 - is56);
icommon_product2 = xC4S4 * (id12 + id56);
DOROUND(icommon_product1)
DOROUND(icommon_product2)
icommon_product1 >>= SHIFT_BITS;
icommon_product2 >>= SHIFT_BITS;
temp1 = xC4S4 * (is0734 + is1256);
temp2 = xC4S4 * (is0734 - is1256);
DOROUND(temp1);
DOROUND(temp2);
temp1 >>= SHIFT_BITS;
temp2 >>= SHIFT_BITS;
op[0 * 8] = (temp1 + FINAL_ROUNDING) >> FINAL_SHIFT;
op[4 * 8] = (temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
// Define inputs to rotation for outputs 2 and 6
irot_input_x = id12 - id56;
irot_input_y = is07 - is34;
// Apply rotation for outputs 2 and 6.
temp1 = xC6S2 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC2S6 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[2 * 8] = (temp1 + temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
temp1 = xC6S2 * irot_input_y;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC2S6 * irot_input_x;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[6 * 8] = (temp1 - temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
// Define inputs to rotation for outputs 1 and 7
irot_input_x = icommon_product1 + id07;
irot_input_y = -(id34 + icommon_product2);
// Apply rotation for outputs 1 and 7.
temp1 = xC1S7 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC7S1 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[1 * 8] = (temp1 - temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
temp1 = xC7S1 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC1S7 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[7 * 8] = (temp1 + temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
// Define inputs to rotation for outputs 3 and 5
irot_input_x = id07 - icommon_product1;
irot_input_y = id34 - icommon_product2;
// Apply rotation for outputs 3 and 5.
temp1 = xC3S5 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC5S3 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[3 * 8] = (temp1 - temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
temp1 = xC5S3 * irot_input_x;
DOROUND(temp1);
temp1 >>= SHIFT_BITS;
temp2 = xC3S5 * irot_input_y;
DOROUND(temp2);
temp2 >>= SHIFT_BITS;
op[5 * 8] = (temp1 + temp2 + FINAL_ROUNDING) >> FINAL_SHIFT;
// Increment data pointer for next column.
ip++;
op++;
}
}
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;
}
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;
short *ip = input;
short *op = output;
int pitch_short = pitch >> 1;
for (i = 0; i < 4; i++) {
a1 = ip[0 * pitch_short] + ip[3 * pitch_short];
b1 = ip[1 * pitch_short] + ip[2 * pitch_short];
c1 = ip[1 * pitch_short] - ip[2 * pitch_short];
d1 = ip[0 * pitch_short] - ip[3 * pitch_short];
op[0] = (a1 + b1 + 1) >> 1;
op[4] = (c1 + d1) >> 1;
op[8] = (a1 - b1) >> 1;
op[12] = (d1 - c1) >> 1;
ip++;
op++;
}
ip = output;
op = output;
for (i = 0; i < 4; i++) {
a1 = ip[0] + ip[3];
b1 = ip[1] + ip[2];
c1 = ip[1] - ip[2];
d1 = ip[0] - ip[3];
op[0] = (a1 + b1 + 1) >> 1;
op[1] = (c1 + d1) >> 1;
op[2] = (a1 - b1) >> 1;
op[3] = (d1 - c1) >> 1;
ip += 4;
op += 4;
}
}
#if CONFIG_LOSSLESS
void vp8_short_walsh4x4_lossless_c(short *input, short *output, int pitch) {
int i;
int a1, b1, c1, d1;
short *ip = input;
short *op = output;
int pitch_short = pitch >> 1;
for (i = 0; i < 4; i++) {
a1 = (ip[0 * pitch_short] + ip[3 * pitch_short]) >> Y2_WHT_UPSCALE_FACTOR;
b1 = (ip[1 * pitch_short] + ip[2 * pitch_short]) >> Y2_WHT_UPSCALE_FACTOR;
c1 = (ip[1 * pitch_short] - ip[2 * pitch_short]) >> Y2_WHT_UPSCALE_FACTOR;
d1 = (ip[0 * pitch_short] - ip[3 * pitch_short]) >> Y2_WHT_UPSCALE_FACTOR;
op[0] = (a1 + b1 + 1) >> 1;
op[4] = (c1 + d1) >> 1;
op[8] = (a1 - b1) >> 1;
op[12] = (d1 - c1) >> 1;
ip++;
op++;
}
ip = output;
op = output;
for (i = 0; i < 4; i++) {
a1 = ip[0] + ip[3];
b1 = ip[1] + ip[2];
c1 = ip[1] - ip[2];
d1 = ip[0] - ip[3];
op[0] = ((a1 + b1 + 1) >> 1) << Y2_WHT_UPSCALE_FACTOR;
op[1] = ((c1 + d1) >> 1) << Y2_WHT_UPSCALE_FACTOR;
op[2] = ((a1 - b1) >> 1) << Y2_WHT_UPSCALE_FACTOR;
op[3] = ((d1 - c1) >> 1) << Y2_WHT_UPSCALE_FACTOR;
ip += 4;
op += 4;
}
}
void vp8_short_walsh4x4_x8_c(short *input, short *output, int pitch) {
int i;
int a1, b1, c1, d1;
short *ip = input;
short *op = output;
int pitch_short = pitch >> 1;
for (i = 0; i < 4; i++) {
a1 = ip[0 * pitch_short] + ip[3 * pitch_short];
b1 = ip[1 * pitch_short] + ip[2 * pitch_short];
c1 = ip[1 * pitch_short] - ip[2 * pitch_short];
d1 = ip[0 * pitch_short] - ip[3 * pitch_short];
op[0] = (a1 + b1 + 1) >> 1;
op[4] = (c1 + d1) >> 1;
op[8] = (a1 - b1) >> 1;
op[12] = (d1 - c1) >> 1;
ip++;
op++;
}
ip = output;
op = output;
for (i = 0; i < 4; i++) {
a1 = ip[0] + ip[3];
b1 = ip[1] + ip[2];
c1 = ip[1] - ip[2];
d1 = ip[0] - ip[3];
op[0] = ((a1 + b1 + 1) >> 1) << WHT_UPSCALE_FACTOR;
op[1] = ((c1 + d1) >> 1) << WHT_UPSCALE_FACTOR;
op[2] = ((a1 - b1) >> 1) << WHT_UPSCALE_FACTOR;
op[3] = ((d1 - c1) >> 1) << WHT_UPSCALE_FACTOR;
ip += 4;
op += 4;
}
}
void vp8_short_walsh8x4_x8_c(short *input, short *output, int pitch) {
vp8_short_walsh4x4_x8_c(input, output, pitch);
vp8_short_walsh4x4_x8_c(input + 4, output + 16, pitch);
}
#endif