1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
/*
Copyright 2018 Google Inc. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS-IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include "dsp/multi_channel_iir.h"
#include <memory>
#include <vector>
#include "third_party/googletest/googletest/include/gtest/gtest.h"
#include "base/constants_and_types.h"
#include "base/logging.h"
namespace vraudio {
namespace {
const size_t kFramesPerBuffer = 4;
// Fills a channel buffer with each of the values passed |num_channels| times.
void FillChannels(const std::vector<float>& values, size_t num_channels,
AudioBuffer::Channel* buffer) {
DCHECK_EQ(values.size() * num_channels, buffer->size());
size_t offset = 0;
for (auto value : values) {
std::fill_n(buffer->begin() + offset, num_channels, value);
offset += num_channels;
}
}
// Compares the contents of the |input| to the corresponding section of the
// |expected| vector.
void CompareMultiChannelOutput(const std::vector<std::vector<float>>& expected,
size_t offset, size_t num_channels,
const AudioBuffer::Channel& input) {
DCHECK_GE(expected[0].size(), kFramesPerBuffer + offset);
for (size_t channel = 0; channel < num_channels; ++channel) {
for (size_t frame = 0; frame < kFramesPerBuffer; ++frame) {
EXPECT_NEAR(expected[channel][frame + offset],
input[frame * num_channels + channel], kEpsilonFloat);
}
}
}
// Tests that the |MultiChannelIir| can filter a single channel of input
// simultaneously with four different biquad filters.
TEST(MultiChannelIirTest, MultipleFilterSetProcessTest) {
const std::vector<std::vector<float>> numerators({{1.0f, 3.0f, 5.0f},
{2.0f, 2.0f, 4.0f},
{1.0f, 2.0f, 2.0f},
{2.0f, 4.0f, 2.0f}});
const std::vector<std::vector<float>> denominators({{1.0f, 1.0f, 0.0f},
{2.0f, 2.0f, 0.0f},
{1.0f, 1.0f, 0.0f},
{2.0f, 2.0f, 0.0f}});
const std::vector<float> initial_input({1.0f, 4.0f, 6.0f, 0.0f});
const std::vector<float> zero_input({0.0f, 0.0f, 0.0f, 0.0f});
// These values have been determined through the MATLAB commands:
// filter([1 3 5], [1 1 0], [1 4 6 0, 0 0 0 0, 0 0 0 0])
// filter([2 2 4], [2 2 0], [1 4 6 0, 0 0 0 0, 0 0 0 0])
// filter([1 2 2], [1 1 0], [1 4 6 0, 0 0 0 0, 0 0 0 0])
// filter([2 4 2], [2 2 0], [1 4 6 0, 0 0 0 0, 0 0 0 0])
const std::vector<std::vector<float>> kExpectedOutputs = {
{1.0f, 6.0f, 17.0f, 21.0f, 9.0f, -9.0f, 9.0f, -9.0f, 9.0f, -9.0f, 9.0f,
-9.0f},
{1.0f, 4.0f, 8.0f, 6.0f, 6.0f, -6.0f, 6.0f, -6.0f, 6.0f, -6.0f, 6.0f,
-6.0f},
{1.0f, 5.0f, 11.0f, 9.0f, 3.0f, -3.0f, 3.0f, -3.0f, 3.0f, -3.0f, 3.0f,
-3.0f},
{1.0f, 5.0f, 10.0f, 6.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f,
0.0f}};
const size_t num_channels = numerators.size();
AudioBuffer interleaved_buffer(kNumMonoChannels,
num_channels * kFramesPerBuffer);
std::unique_ptr<MultiChannelIir> filter = MultiChannelIir::Create(
num_channels, kFramesPerBuffer, numerators, denominators);
// Filter the initial buffer [1 4 6 0], and compare the output to the first
// kFramesPerBuffer entries in |kExpectedOutputs|.
FillChannels(initial_input, num_channels, &interleaved_buffer[0]);
filter->Process(&(interleaved_buffer[0]));
CompareMultiChannelOutput(kExpectedOutputs, /*offset*/ 0, num_channels,
interleaved_buffer[0]);
// Filter zeros [0 0 0 0], and compare the output to the next kFramesPerBuffer
// entries in |kExpectedOutputs|.
FillChannels(zero_input, num_channels, &interleaved_buffer[0]);
filter->Process(&(interleaved_buffer[0]));
CompareMultiChannelOutput(kExpectedOutputs, kFramesPerBuffer, num_channels,
interleaved_buffer[0]);
// Filter zeros [0 0 0 0], and compare the output to the next kFramesPerBuffer
// entries in |kExpectedOutputs|.
FillChannels(zero_input, num_channels, &interleaved_buffer[0]);
filter->Process(&(interleaved_buffer[0]));
CompareMultiChannelOutput(kExpectedOutputs, 2 * kFramesPerBuffer,
num_channels, interleaved_buffer[0]);
}
} // namespace
} // namespace vraudio
|
