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
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
/*
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 "geometrical_acoustics/estimating_rt60.h"
#include <cmath>
#include <memory>
#include <vector>
#include "third_party/googletest/googletest/include/gtest/gtest.h"
#include "base/constants_and_types.h"
#include "geometrical_acoustics/impulse_response_computer.h"
#include "geometrical_acoustics/test_util.h"
#include "platforms/common/room_effects_utils.h"
namespace vraudio {
namespace {
class EstimateRT60Test : public testing::Test {
public:
EstimateRT60Test() {
Vertex min_corner = {cube_center_[0] - 0.5f * cube_dimensions_[0],
cube_center_[1] - 0.5f * cube_dimensions_[1],
cube_center_[2] - 0.5f * cube_dimensions_[2]};
Vertex max_corner = {cube_center_[0] + 0.5f * cube_dimensions_[0],
cube_center_[1] + 0.5f * cube_dimensions_[1],
cube_center_[2] + 0.5f * cube_dimensions_[2]};
BuildTestBoxScene(min_corner, max_corner, &cube_vertices_, &cube_triangles_,
&cube_wall_triangles_);
}
protected:
std::vector<float> CollectImpulseResponsesAndEstimateRT60(
const std::vector<Path>& paths, SceneManager* scene_manager) {
// Listener and impulse response computer.
std::unique_ptr<std::vector<AcousticListener>> listeners(
new std::vector<AcousticListener>);
listeners->emplace_back(Eigen::Vector3f(cube_center_),
impulse_response_num_samples_);
ImpulseResponseComputer impulse_response_computer(
listener_sphere_radius_, sampling_rate_, std::move(listeners),
scene_manager);
// Collect impulse responses.
impulse_response_computer.CollectContributions(paths);
const std::array<std::vector<float>, kNumReverbOctaveBands>&
energy_impulse_responses =
impulse_response_computer.GetFinalizedListeners()
.at(0)
.energy_impulse_responses;
// Estimate RT60 values.
std::vector<float> output_rt60_values(kNumReverbOctaveBands, 0.0f);
for (size_t band = 0; band < kNumReverbOctaveBands; ++band) {
output_rt60_values[band] =
EstimateRT60(energy_impulse_responses[band], sampling_rate_);
}
return output_rt60_values;
}
// Ray-tracing related fields.
const float sampling_rate_ = 48000.0f;
const float listener_sphere_radius_ = 0.1f;
const size_t impulse_response_num_samples_ = 96000;
Eigen::Vector3f listener_position_;
// Data describing a cube scene.
std::vector<Vertex> cube_vertices_;
std::vector<Triangle> cube_triangles_;
const float cube_center_[3] = {0.5f, 0.5f, 0.5f};
const float cube_dimensions_[3] = {1.0f, 1.0f, 1.0f};
std::vector<MaterialName> wall_materials_;
// Triangles for six walls of a cube. Useful for assigning surface materials.
std::vector<std::unordered_set<unsigned int>> cube_wall_triangles_;
};
// Tests that estimating from an empty impulse responses vector fails.
TEST_F(EstimateRT60Test, EstimateFromEmptyImpulseResponsesFails) {
std::vector<float> empty_energy_impulse_responses;
// Expect that the estimation function returns 0.
EXPECT_EQ(0.0f, EstimateRT60(empty_energy_impulse_responses, sampling_rate_));
}
// Tests that if the impulse responses are increasing in energy and therefore
// RT60 is not defined, the estimation returns 0.
TEST_F(EstimateRT60Test, EstimateFromIncreasingEnergyFails) {
std::vector<float> increasing_energy_impulse_responses(1000, 0.0f);
for (size_t i = 0; i < 1000; ++i) {
increasing_energy_impulse_responses[i] = static_cast<float>(i) * 1e-3f;
}
// Expect that the estimation function returns 0.
EXPECT_EQ(0.0f,
EstimateRT60(increasing_energy_impulse_responses, sampling_rate_));
}
// Tests that if estimating from perfectly-constructed, exponentially-decaying
// impulse responses, then the known RT60 is returned.
TEST_F(EstimateRT60Test, EstimateFromExponentiallyDecayingResponses) {
std::vector<float> energy_impulse_responses(1000, 0.0f);
const std::vector<float> expected_RT60s = {0.05f, 0.1f, 0.2f,
0.5f, 1.0f, 2.0f};
for (const float expected_RT60 : expected_RT60s) {
// Construct an exponentially decaying reverb tail with a known RT60, whose
// energy at index i is 10^(6 * i / sampling_rate / RT60).
for (size_t i = 1; i < energy_impulse_responses.size(); ++i) {
energy_impulse_responses[i] = std::pow(
10.0f, -(static_cast<float>(6 * i) / sampling_rate_ / expected_RT60));
}
// Expect that the estimated RT60 is close to the expected one.
EXPECT_NEAR(expected_RT60,
EstimateRT60(energy_impulse_responses, sampling_rate_), 0.01f);
}
}
// Tests that RT60s estimated from a cube scene agrees with those computed
// using RoomEffectsUtils::ComputeReverbProperties() (which uses Eyring's
// equation under the hood).
TEST_F(EstimateRT60Test, EstimateFromCubeSceneAgreesWithHeuristics) {
wall_materials_ = std::vector<MaterialName>{
MaterialName::kPlasterSmooth,
MaterialName::kLinoleumOnConcrete,
MaterialName::kConcreteBlockPainted,
MaterialName::kGlassThin,
MaterialName::kBrickBare,
MaterialName::kPlywoodPanel,
};
// Trace rays in a cube scene and estimate RT60s.
SceneManager scene_manager;
std::vector<Path> paths = TracePathsInTestcene(
100 /* min_num_rays */, 100 /* max_depth */,
1e-12f /* energy_threshold */, cube_center_, cube_vertices_,
cube_triangles_, cube_wall_triangles_, wall_materials_, &scene_manager);
std::vector<float> estimated_rt60_values =
CollectImpulseResponsesAndEstimateRT60(paths, &scene_manager);
// A default room properties with some fields set to non-default values.
RoomProperties room_properties;
room_properties.position[0] = cube_center_[0];
room_properties.position[1] = cube_center_[1];
room_properties.position[2] = cube_center_[2];
room_properties.dimensions[0] = cube_dimensions_[0];
room_properties.dimensions[1] = cube_dimensions_[1];
room_properties.dimensions[2] = cube_dimensions_[2];
for (size_t wall = 0; wall < kNumRoomSurfaces; ++wall) {
room_properties.material_names[wall] = wall_materials_[wall];
}
// Reverb properties computed using heuristics.
const ReverbProperties reverb_properties =
ComputeReverbProperties(room_properties);
// Compare the two sets of RT60s.
const float rt60_error_tolerance = 0.05f;
for (size_t band = 0; band < kNumReverbOctaveBands; ++band) {
const float estimated_rt60 = estimated_rt60_values[band];
const float expected_rt60 = reverb_properties.rt60_values[band];
EXPECT_NEAR(estimated_rt60, expected_rt60, rt60_error_tolerance);
}
}
} // namespace
} // namespace vraudio
|
