1 files changed, 117 insertions, 0 deletions
diff --git a/src/3rdparty/resonance-audio/resonance_audio/dsp/multi_channel_iir_test.cc b/src/3rdparty/resonance-audio/resonance_audio/dsp/multi_channel_iir_test.cc
new file mode 100644
index 000000000..3c291196e
--- /dev/null
+++ b/src/3rdparty/resonance-audio/resonance_audio/dsp/multi_channel_iir_test.cc
@@ -0,0 +1,117 @@
+/*
+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