1 /*
2 * Copyright (c) 2013 The WebM project authors. All Rights Reserved.
3 *
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.
9 */
10
11 #include <math.h>
12 #include <stddef.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <sys/types.h>
17
18 #include "./vp8_rtcd.h"
19
20 #include "test/acm_random.h"
21 #include "third_party/googletest/src/include/gtest/gtest.h"
22 #include "vpx/vpx_integer.h"
23
24 namespace {
25
26 const int cospi8sqrt2minus1 = 20091;
27 const int sinpi8sqrt2 = 35468;
28
reference_idct4x4(const int16_t * input,int16_t * output)29 void reference_idct4x4(const int16_t *input, int16_t *output) {
30 const int16_t *ip = input;
31 int16_t *op = output;
32
33 for (int i = 0; i < 4; ++i) {
34 const int a1 = ip[0] + ip[8];
35 const int b1 = ip[0] - ip[8];
36 const int temp1 = (ip[4] * sinpi8sqrt2) >> 16;
37 const int temp2 = ip[12] + ((ip[12] * cospi8sqrt2minus1) >> 16);
38 const int c1 = temp1 - temp2;
39 const int temp3 = ip[4] + ((ip[4] * cospi8sqrt2minus1) >> 16);
40 const int temp4 = (ip[12] * sinpi8sqrt2) >> 16;
41 const int d1 = temp3 + temp4;
42 op[0] = a1 + d1;
43 op[12] = a1 - d1;
44 op[4] = b1 + c1;
45 op[8] = b1 - c1;
46 ++ip;
47 ++op;
48 }
49 ip = output;
50 op = output;
51 for (int i = 0; i < 4; ++i) {
52 const int a1 = ip[0] + ip[2];
53 const int b1 = ip[0] - ip[2];
54 const int temp1 = (ip[1] * sinpi8sqrt2) >> 16;
55 const int temp2 = ip[3] + ((ip[3] * cospi8sqrt2minus1) >> 16);
56 const int c1 = temp1 - temp2;
57 const int temp3 = ip[1] + ((ip[1] * cospi8sqrt2minus1) >> 16);
58 const int temp4 = (ip[3] * sinpi8sqrt2) >> 16;
59 const int d1 = temp3 + temp4;
60 op[0] = (a1 + d1 + 4) >> 3;
61 op[3] = (a1 - d1 + 4) >> 3;
62 op[1] = (b1 + c1 + 4) >> 3;
63 op[2] = (b1 - c1 + 4) >> 3;
64 ip += 4;
65 op += 4;
66 }
67 }
68
69 using libvpx_test::ACMRandom;
70
TEST(VP8FdctTest,SignBiasCheck)71 TEST(VP8FdctTest, SignBiasCheck) {
72 ACMRandom rnd(ACMRandom::DeterministicSeed());
73 int16_t test_input_block[16];
74 int16_t test_output_block[16];
75 const int pitch = 8;
76 int count_sign_block[16][2];
77 const int count_test_block = 1000000;
78
79 memset(count_sign_block, 0, sizeof(count_sign_block));
80
81 for (int i = 0; i < count_test_block; ++i) {
82 // Initialize a test block with input range [-255, 255].
83 for (int j = 0; j < 16; ++j)
84 test_input_block[j] = rnd.Rand8() - rnd.Rand8();
85
86 vp8_short_fdct4x4_c(test_input_block, test_output_block, pitch);
87
88 for (int j = 0; j < 16; ++j) {
89 if (test_output_block[j] < 0)
90 ++count_sign_block[j][0];
91 else if (test_output_block[j] > 0)
92 ++count_sign_block[j][1];
93 }
94 }
95
96 bool bias_acceptable = true;
97 for (int j = 0; j < 16; ++j)
98 bias_acceptable = bias_acceptable &&
99 (abs(count_sign_block[j][0] - count_sign_block[j][1]) < 10000);
100
101 EXPECT_EQ(true, bias_acceptable)
102 << "Error: 4x4 FDCT has a sign bias > 1% for input range [-255, 255]";
103
104 memset(count_sign_block, 0, sizeof(count_sign_block));
105
106 for (int i = 0; i < count_test_block; ++i) {
107 // Initialize a test block with input range [-15, 15].
108 for (int j = 0; j < 16; ++j)
109 test_input_block[j] = (rnd.Rand8() >> 4) - (rnd.Rand8() >> 4);
110
111 vp8_short_fdct4x4_c(test_input_block, test_output_block, pitch);
112
113 for (int j = 0; j < 16; ++j) {
114 if (test_output_block[j] < 0)
115 ++count_sign_block[j][0];
116 else if (test_output_block[j] > 0)
117 ++count_sign_block[j][1];
118 }
119 }
120
121 bias_acceptable = true;
122 for (int j = 0; j < 16; ++j)
123 bias_acceptable = bias_acceptable &&
124 (abs(count_sign_block[j][0] - count_sign_block[j][1]) < 100000);
125
126 EXPECT_EQ(true, bias_acceptable)
127 << "Error: 4x4 FDCT has a sign bias > 10% for input range [-15, 15]";
128 };
129
TEST(VP8FdctTest,RoundTripErrorCheck)130 TEST(VP8FdctTest, RoundTripErrorCheck) {
131 ACMRandom rnd(ACMRandom::DeterministicSeed());
132 int max_error = 0;
133 double total_error = 0;
134 const int count_test_block = 1000000;
135 for (int i = 0; i < count_test_block; ++i) {
136 int16_t test_input_block[16];
137 int16_t test_temp_block[16];
138 int16_t test_output_block[16];
139
140 // Initialize a test block with input range [-255, 255].
141 for (int j = 0; j < 16; ++j)
142 test_input_block[j] = rnd.Rand8() - rnd.Rand8();
143
144 const int pitch = 8;
145 vp8_short_fdct4x4_c(test_input_block, test_temp_block, pitch);
146 reference_idct4x4(test_temp_block, test_output_block);
147
148 for (int j = 0; j < 16; ++j) {
149 const int diff = test_input_block[j] - test_output_block[j];
150 const int error = diff * diff;
151 if (max_error < error)
152 max_error = error;
153 total_error += error;
154 }
155 }
156
157 EXPECT_GE(1, max_error )
158 << "Error: FDCT/IDCT has an individual roundtrip error > 1";
159
160 EXPECT_GE(count_test_block, total_error)
161 << "Error: FDCT/IDCT has average roundtrip error > 1 per block";
162 };
163
164 } // namespace
165