2 * Copyright (c) 2012 The WebM project authors. All Rights Reserved.
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
15 #include "third_party/googletest/src/include/gtest/gtest.h"
21 #include "acm_random.h"
22 #include "vpx/vpx_integer.h"
24 using libvpx_test::ACMRandom;
29 static int round(double x) {
31 return (int)ceil(x - 0.5);
33 return (int)floor(x + 0.5);
37 void reference_dct_1d(double input[8], double output[8]) {
38 const double kPi = 3.141592653589793238462643383279502884;
39 const double kInvSqrt2 = 0.707106781186547524400844362104;
40 for (int k = 0; k < 8; k++) {
42 for (int n = 0; n < 8; n++)
43 output[k] += input[n]*cos(kPi*(2*n+1)*k/16.0);
45 output[k] = output[k]*kInvSqrt2;
49 void reference_dct_2d(int16_t input[64], double output[64]) {
50 // First transform columns
51 for (int i = 0; i < 8; ++i) {
52 double temp_in[8], temp_out[8];
53 for (int j = 0; j < 8; ++j)
54 temp_in[j] = input[j*8 + i];
55 reference_dct_1d(temp_in, temp_out);
56 for (int j = 0; j < 8; ++j)
57 output[j*8 + i] = temp_out[j];
59 // Then transform rows
60 for (int i = 0; i < 8; ++i) {
61 double temp_in[8], temp_out[8];
62 for (int j = 0; j < 8; ++j)
63 temp_in[j] = output[j + i*8];
64 reference_dct_1d(temp_in, temp_out);
65 for (int j = 0; j < 8; ++j)
66 output[j + i*8] = temp_out[j];
68 // Scale by some magic number
69 for (int i = 0; i < 64; ++i)
73 void reference_idct_1d(double input[8], double output[8]) {
74 const double kPi = 3.141592653589793238462643383279502884;
75 const double kSqrt2 = 1.414213562373095048801688724209698;
76 for (int k = 0; k < 8; k++) {
78 for (int n = 0; n < 8; n++) {
79 output[k] += input[n]*cos(kPi*(2*k+1)*n/16.0);
81 output[k] = output[k]/kSqrt2;
86 void reference_idct_2d(double input[64], int16_t output[64]) {
87 double out[64], out2[64];
88 // First transform rows
89 for (int i = 0; i < 8; ++i) {
90 double temp_in[8], temp_out[8];
91 for (int j = 0; j < 8; ++j)
92 temp_in[j] = input[j + i*8];
93 reference_idct_1d(temp_in, temp_out);
94 for (int j = 0; j < 8; ++j)
95 out[j + i*8] = temp_out[j];
97 // Then transform columns
98 for (int i = 0; i < 8; ++i) {
99 double temp_in[8], temp_out[8];
100 for (int j = 0; j < 8; ++j)
101 temp_in[j] = out[j*8 + i];
102 reference_idct_1d(temp_in, temp_out);
103 for (int j = 0; j < 8; ++j)
104 out2[j*8 + i] = temp_out[j];
106 for (int i = 0; i < 64; ++i)
107 output[i] = round(out2[i]/32);
110 TEST(VP9Idct8x8Test, AccuracyCheck) {
111 ACMRandom rnd(ACMRandom::DeterministicSeed());
112 const int count_test_block = 10000;
113 for (int i = 0; i < count_test_block; ++i) {
114 int16_t input[64], coeff[64];
116 uint8_t dst[64], src[64];
118 for (int j = 0; j < 64; ++j) {
119 src[j] = rnd.Rand8();
120 dst[j] = rnd.Rand8();
122 // Initialize a test block with input range [-255, 255].
123 for (int j = 0; j < 64; ++j)
124 input[j] = src[j] - dst[j];
126 reference_dct_2d(input, output_r);
127 for (int j = 0; j < 64; ++j)
128 coeff[j] = round(output_r[j]);
129 vp9_short_idct8x8_add_c(coeff, dst, 8);
130 for (int j = 0; j < 64; ++j) {
131 const int diff = dst[j] - src[j];
132 const int error = diff * diff;
134 << "Error: 8x8 FDCT/IDCT has error " << error
135 << " at index " << j;