1 files changed, 59 insertions, 0 deletions
diff --git a/src/3rdparty/resonance-audio/resonance_audio/dsp/mono_pole_filter_test.cc b/src/3rdparty/resonance-audio/resonance_audio/dsp/mono_pole_filter_test.cc
new file mode 100644
index 000000000..c93b4fab7
--- /dev/null
+++ b/src/3rdparty/resonance-audio/resonance_audio/dsp/mono_pole_filter_test.cc
@@ -0,0 +1,59 @@
+/*
+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/mono_pole_filter.h"
+
+#include <cmath>
+
+#include "third_party/googletest/googletest/include/gtest/gtest.h"
+#include "base/constants_and_types.h"
+#include "base/misc_math.h"
+
+namespace vraudio {
+
+namespace {
+
+const float kCoefficient = 0.5f;
+const size_t kFramesPerBuffer = 10;
+
+// Tests that the filter correctly implements the difference equation.
+TEST(MonoPoleFilterTest, ImpulseResponseTest) {
+  MonoPoleFilter filter(kCoefficient);
+  AudioBuffer buffer(1U, kFramesPerBuffer);
+  buffer.Clear();
+  buffer[0][0] = 1.0f;
+  EXPECT_TRUE(filter.Filter(buffer[0], &buffer[0]));
+  for (size_t i = 0; i < kFramesPerBuffer; ++i) {
+    // The impulse response of this filter (for coefficient a), should be:
+    // d[n] = (1 - a) * a^n
+    const float expected =
+        (1.0f - kCoefficient) * IntegerPow(kCoefficient, static_cast<int>(i));
+    EXPECT_NEAR(buffer[0][i], expected, kEpsilonFloat);
+  }
+}
+
+// Tests that no processing is performed when the filter is allpass.
+TEST(MonoPoleFilterTest, AllPassNoProcessingTest) {
+  MonoPoleFilter filter(0.0f);
+  AudioBuffer buffer(1U, kFramesPerBuffer);
+  buffer.Clear();
+  buffer[0][0] = 1.0f;
+  EXPECT_FALSE(filter.Filter(buffer[0], &buffer[0]));
+}
+
+}  // namespace
+
+}  // namespace vraudio