/*
* Copyright (c) 2016, Alliance for Open Media. All rights reserved.
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#include <assert.h>
#include "aom_dsp/txfm_common.h"
#include "config/aom_dsp_rtcd.h"
void aom_fdct4x4_c(
const int16_t *input, tran_low_t *output,
int stride) {
// The 2D transform is done with two passes which are actually pretty
// similar. In the first one, we transform the columns and transpose
// the results. In the second one, we transform the rows.
// We need an intermediate buffer between passes.
tran_low_t intermediate[4 * 4];
const tran_low_t *in_low = NULL;
tran_low_t *out = intermediate;
// Do the two transform passes
for (
int pass = 0; pass < 2; ++pass) {
tran_high_t in_high[4];
// canbe16
tran_high_t step[4];
// canbe16
tran_low_t temp[4];
for (
int i = 0; i < 4; ++i) {
// Load inputs.
if (pass == 0) {
in_high[0] = input[0 * stride] * 16;
in_high[1] = input[1 * stride] * 16;
in_high[2] = input[2 * stride] * 16;
in_high[3] = input[3 * stride] * 16;
if (i == 0 && in_high[0]) {
++in_high[0];
}
++input;
// Next column
}
else {
assert(in_low != NULL);
in_high[0] = in_low[0 * 4];
in_high[1] = in_low[1 * 4];
in_high[2] = in_low[2 * 4];
in_high[3] = in_low[3 * 4];
++in_low;
// Next column (which is a transposed row)
}
// Transform.
step[0] = in_high[0] + in_high[3];
step[1] = in_high[1] + in_high[2];
step[2] = in_high[1] - in_high[2];
step[3] = in_high[0] - in_high[3];
temp[0] = (tran_low_t)fdct_round_shift((step[0] + step[1]) * cospi_16_64);
temp[2] = (tran_low_t)fdct_round_shift((step[0] - step[1]) * cospi_16_64);
temp[1] = (tran_low_t)fdct_round_shift(step[2] * cospi_24_64 +
step[3] * cospi_8_64);
temp[3] = (tran_low_t)fdct_round_shift(-step[2] * cospi_8_64 +
step[3] * cospi_24_64);
// Only transpose the first pass.
if (pass == 0) {
out[0] = temp[0];
out[1] = temp[1];
out[2] = temp[2];
out[3] = temp[3];
out += 4;
}
else {
out[0 * 4] = temp[0];
out[1 * 4] = temp[1];
out[2 * 4] = temp[2];
out[3 * 4] = temp[3];
++out;
}
}
// Setup in/out for next pass.
in_low = intermediate;
out = output;
}
for (
int i = 0; i < 4; ++i) {
for (
int j = 0; j < 4; ++j)
output[j + i * 4] = (output[j + i * 4] + 1) >> 2;
}
}
void aom_fdct4x4_lp_c(
const int16_t *input, int16_t *output,
int stride) {
// The 2D transform is done with two passes which are actually pretty
// similar. In the first one, we transform the columns and transpose
// the results. In the second one, we transform the rows.
// We need an intermediate buffer between passes.
int16_t intermediate[4 * 4];
const int16_t *in_low = NULL;
int16_t *out = intermediate;
// Do the two transform passes
for (
int pass = 0; pass < 2; ++pass) {
int32_t in_high[4];
// canbe16
int32_t step[4];
// canbe16
int16_t temp[4];
for (
int i = 0; i < 4; ++i) {
// Load inputs.
if (pass == 0) {
in_high[0] = input[0 * stride] * 16;
in_high[1] = input[1 * stride] * 16;
in_high[2] = input[2 * stride] * 16;
in_high[3] = input[3 * stride] * 16;
++input;
if (i == 0 && in_high[0]) {
++in_high[0];
}
}
else {
assert(in_low != NULL);
in_high[0] = in_low[0 * 4];
in_high[1] = in_low[1 * 4];
in_high[2] = in_low[2 * 4];
in_high[3] = in_low[3 * 4];
++in_low;
}
// Transform.
step[0] = in_high[0] + in_high[3];
step[1] = in_high[1] + in_high[2];
step[2] = in_high[1] - in_high[2];
step[3] = in_high[0] - in_high[3];
temp[0] = (int16_t)fdct_round_shift((step[0] + step[1]) * cospi_16_64);
temp[2] = (int16_t)fdct_round_shift((step[0] - step[1]) * cospi_16_64);
temp[1] = (int16_t)fdct_round_shift(step[2] * cospi_24_64 +
step[3] * cospi_8_64);
temp[3] = (int16_t)fdct_round_shift(-step[2] * cospi_8_64 +
step[3] * cospi_24_64);
// Only transpose the first pass.
if (pass == 0) {
out[0] = temp[0];
out[1] = temp[1];
out[2] = temp[2];
out[3] = temp[3];
out += 4;
}
else {
out[0 * 4] = temp[0];
out[1 * 4] = temp[1];
out[2 * 4] = temp[2];
out[3 * 4] = temp[3];
++out;
}
}
// Setup in/out for next pass.
in_low = intermediate;
out = output;
}
for (
int i = 0; i < 4; ++i) {
for (
int j = 0; j < 4; ++j)
output[j + i * 4] = (output[j + i * 4] + 1) >> 2;
}
}
#if CONFIG_INTERNAL_STATS
void aom_fdct8x8_c(
const int16_t *input, tran_low_t *final_output,
int stride) {
int i, j;
tran_low_t intermediate[64];
int pass;
tran_low_t *output = intermediate;
const tran_low_t *in = NULL;
// Transform columns
for (pass = 0; pass < 2; ++pass) {
tran_high_t s0, s1, s2, s3, s4, s5, s6, s7;
// canbe16
tran_high_t t0, t1, t2, t3;
// needs32
tran_high_t x0, x1, x2, x3;
// canbe16
for (i = 0; i < 8; i++) {
// stage 1
if (pass == 0) {
s0 = (input[0 * stride] + input[7 * stride]) * 4;
s1 = (input[1 * stride] + input[6 * stride]) * 4;
s2 = (input[2 * stride] + input[5 * stride]) * 4;
s3 = (input[3 * stride] + input[4 * stride]) * 4;
s4 = (input[3 * stride] - input[4 * stride]) * 4;
s5 = (input[2 * stride] - input[5 * stride]) * 4;
s6 = (input[1 * stride] - input[6 * stride]) * 4;
s7 = (input[0 * stride] - input[7 * stride]) * 4;
++input;
}
else {
s0 = in[0 * 8] + in[7 * 8];
s1 = in[1 * 8] + in[6 * 8];
s2 = in[2 * 8] + in[5 * 8];
s3 = in[3 * 8] + in[4 * 8];
s4 = in[3 * 8] - in[4 * 8];
s5 = in[2 * 8] - in[5 * 8];
s6 = in[1 * 8] - in[6 * 8];
s7 = in[0 * 8] - in[7 * 8];
++in;
}
// fdct4(step, step);
x0 = s0 + s3;
x1 = s1 + s2;
x2 = s1 - s2;
x3 = s0 - s3;
t0 = (x0 + x1) * cospi_16_64;
t1 = (x0 - x1) * cospi_16_64;
t2 = x2 * cospi_24_64 + x3 * cospi_8_64;
t3 = -x2 * cospi_8_64 + x3 * cospi_24_64;
output[0] = (tran_low_t)fdct_round_shift(t0);
output[2] = (tran_low_t)fdct_round_shift(t2);
output[4] = (tran_low_t)fdct_round_shift(t1);
output[6] = (tran_low_t)fdct_round_shift(t3);
// Stage 2
t0 = (s6 - s5) * cospi_16_64;
t1 = (s6 + s5) * cospi_16_64;
t2 = fdct_round_shift(t0);
t3 = fdct_round_shift(t1);
// Stage 3
x0 = s4 + t2;
x1 = s4 - t2;
x2 = s7 - t3;
x3 = s7 + t3;
// Stage 4
t0 = x0 * cospi_28_64 + x3 * cospi_4_64;
t1 = x1 * cospi_12_64 + x2 * cospi_20_64;
t2 = x2 * cospi_12_64 + x1 * -cospi_20_64;
t3 = x3 * cospi_28_64 + x0 * -cospi_4_64;
output[1] = (tran_low_t)fdct_round_shift(t0);
output[3] = (tran_low_t)fdct_round_shift(t2);
output[5] = (tran_low_t)fdct_round_shift(t1);
output[7] = (tran_low_t)fdct_round_shift(t3);
output += 8;
}
in = intermediate;
output = final_output;
}
// Rows
for (i = 0; i < 8; ++i) {
for (j = 0; j < 8; ++j) final_output[j + i * 8] /= 2;
}
}
#endif // CONFIG_INTERNAL_STATS
#if CONFIG_AV1_HIGHBITDEPTH && CONFIG_INTERNAL_STATS
void aom_highbd_fdct8x8_c(
const int16_t *input, tran_low_t *final_output,
int stride) {
aom_fdct8x8_c(input, final_output, stride);
}
#endif
