| /* |
| * Copyright 2014 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "rtc_base/numerics/exp_filter.h" |
| |
| #include <cmath> |
| |
| #include "test/gtest.h" |
| |
| namespace rtc { |
| |
| TEST(ExpFilterTest, FirstTimeOutputEqualInput) { |
| // No max value defined. |
| ExpFilter filter = ExpFilter(0.9f); |
| filter.Apply(100.0f, 10.0f); |
| |
| // First time, first argument no effect. |
| double value = 10.0f; |
| EXPECT_FLOAT_EQ(value, filter.filtered()); |
| } |
| |
| TEST(ExpFilterTest, SecondTime) { |
| float value; |
| |
| ExpFilter filter = ExpFilter(0.9f); |
| filter.Apply(100.0f, 10.0f); |
| |
| // First time, first argument no effect. |
| value = 10.0f; |
| |
| filter.Apply(10.0f, 20.0f); |
| float alpha = std::pow(0.9f, 10.0f); |
| value = alpha * value + (1.0f - alpha) * 20.0f; |
| EXPECT_FLOAT_EQ(value, filter.filtered()); |
| } |
| |
| TEST(ExpFilterTest, Reset) { |
| ExpFilter filter = ExpFilter(0.9f); |
| filter.Apply(100.0f, 10.0f); |
| |
| filter.Reset(0.8f); |
| filter.Apply(100.0f, 1.0f); |
| |
| // Become first time after a reset. |
| double value = 1.0f; |
| EXPECT_FLOAT_EQ(value, filter.filtered()); |
| } |
| |
| TEST(ExpfilterTest, OutputLimitedByMax) { |
| double value; |
| |
| // Max value defined. |
| ExpFilter filter = ExpFilter(0.9f, 1.0f); |
| filter.Apply(100.0f, 10.0f); |
| |
| // Limited to max value. |
| value = 1.0f; |
| EXPECT_EQ(value, filter.filtered()); |
| |
| filter.Apply(1.0f, 0.0f); |
| value = 0.9f * value; |
| EXPECT_FLOAT_EQ(value, filter.filtered()); |
| } |
| |
| } // namespace rtc |