1 // Copyright 2015 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "media/parsers/vp8_bool_decoder.h"
6
7 #include <stddef.h>
8 #include <stdint.h>
9
10 #include <limits>
11
12 #include "base/macros.h"
13 #include "testing/gtest/include/gtest/gtest.h"
14
15 namespace media {
16
17 const static size_t NUM_BITS_TO_TEST = 100;
18
19 namespace {
20
21 // 100 zeros with probability of 0x80.
22 const uint8_t kDataZerosAndEvenProbabilities[] = {
23 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
24 0x00, 0x00, 0x00};
25
26 // 100 ones with probability of 0x80.
27 const uint8_t kDataOnesAndEvenProbabilities[] = {
28 0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
29 0xff, 0xf0, 0x20};
30
31 // [0, 1, 0, 1, ..., 1] with probability [0, 1, 2, 3, ..., 99].
32 const uint8_t kDataParitiesAndIncreasingProbabilities[] = {
33 0x00, 0x02, 0x08, 0x31, 0x8e, 0xca, 0xab, 0xe2, 0xc8, 0x31, 0x12,
34 0xb3, 0x2c, 0x19, 0x90, 0xc6, 0x6a, 0xeb, 0x17, 0x52, 0x30};
35
36 } // namespace
37
38 class Vp8BoolDecoderTest : public ::testing::Test {
39 public:
40 Vp8BoolDecoderTest() = default;
41
42 protected:
43 // Fixture member, the bool decoder to be tested.
44 Vp8BoolDecoder bd_;
45
46 private:
47 DISALLOW_COPY_AND_ASSIGN(Vp8BoolDecoderTest);
48 };
49
50 #define INITIALIZE(data) ASSERT_TRUE(bd_.Initialize(data, sizeof(data)));
51
TEST_F(Vp8BoolDecoderTest,DecodeBoolsWithZerosAndEvenProbabilities)52 TEST_F(Vp8BoolDecoderTest, DecodeBoolsWithZerosAndEvenProbabilities) {
53 INITIALIZE(kDataZerosAndEvenProbabilities);
54 ASSERT_EQ(0u, bd_.BitOffset());
55 for (size_t i = 0; i < NUM_BITS_TO_TEST; ++i) {
56 bool out = true;
57 ASSERT_TRUE(bd_.ReadBool(&out, 0x80));
58 ASSERT_FALSE(out);
59 ASSERT_EQ(i, bd_.BitOffset());
60 }
61 }
62
TEST_F(Vp8BoolDecoderTest,DecodeLiteralsWithZerosAndEvenProbabilities)63 TEST_F(Vp8BoolDecoderTest, DecodeLiteralsWithZerosAndEvenProbabilities) {
64 INITIALIZE(kDataZerosAndEvenProbabilities);
65
66 int value = 1;
67 ASSERT_TRUE(bd_.ReadLiteral(1, &value));
68 ASSERT_EQ(0, value);
69
70 value = 1;
71 ASSERT_TRUE(bd_.ReadLiteral(32, &value));
72 ASSERT_EQ(0, value);
73
74 value = 1;
75 ASSERT_TRUE(bd_.ReadLiteralWithSign(1, &value));
76 ASSERT_EQ(0, value);
77
78 value = 1;
79 ASSERT_TRUE(bd_.ReadLiteralWithSign(31, &value));
80 ASSERT_EQ(0, value);
81 }
82
TEST_F(Vp8BoolDecoderTest,DecodeBoolsWithOnesAndEvenProbabilities)83 TEST_F(Vp8BoolDecoderTest, DecodeBoolsWithOnesAndEvenProbabilities) {
84 INITIALIZE(kDataOnesAndEvenProbabilities);
85
86 ASSERT_EQ(0u, bd_.BitOffset());
87 for (size_t i = 0; i < NUM_BITS_TO_TEST; ++i) {
88 bool out = false;
89 ASSERT_TRUE(bd_.ReadBool(&out, 0x80));
90 ASSERT_TRUE(out);
91 ASSERT_EQ(i + 1, bd_.BitOffset());
92 }
93 }
94
TEST_F(Vp8BoolDecoderTest,DecodeLiteralsWithOnesAndEvenProbabilities)95 TEST_F(Vp8BoolDecoderTest, DecodeLiteralsWithOnesAndEvenProbabilities) {
96 INITIALIZE(kDataOnesAndEvenProbabilities);
97
98 int value = 0;
99 ASSERT_TRUE(bd_.ReadLiteral(1, &value));
100 EXPECT_EQ(1, value);
101
102 value = 0;
103 ASSERT_TRUE(bd_.ReadLiteral(31, &value));
104 EXPECT_EQ(0x7FFFFFFF, value);
105
106 value = 0;
107 ASSERT_TRUE(bd_.ReadLiteralWithSign(1, &value));
108 EXPECT_EQ(-1, value);
109
110 value = 0;
111 ASSERT_TRUE(bd_.ReadLiteralWithSign(31, &value));
112 EXPECT_EQ(-0x7FFFFFFF, value);
113 }
114
TEST_F(Vp8BoolDecoderTest,DecodeBoolsWithParitiesAndIncreasingProbabilities)115 TEST_F(Vp8BoolDecoderTest, DecodeBoolsWithParitiesAndIncreasingProbabilities) {
116 INITIALIZE(kDataParitiesAndIncreasingProbabilities);
117
118 for (size_t i = 0; i < NUM_BITS_TO_TEST; ++i) {
119 bool out = !(i & 1);
120 ASSERT_LE(i, std::numeric_limits<uint8_t>::max());
121 ASSERT_TRUE(bd_.ReadBool(&out, static_cast<uint8_t>(i)));
122 EXPECT_EQ(out, !!(i & 1));
123 }
124 }
125
126 } // namespace media
127