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Diffstat (limited to '')
-rw-r--r-- | third_party/libwebrtc/modules/audio_mixer/gain_change_calculator.cc | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_mixer/gain_change_calculator.cc b/third_party/libwebrtc/modules/audio_mixer/gain_change_calculator.cc new file mode 100644 index 0000000000..dbd0945239 --- /dev/null +++ b/third_party/libwebrtc/modules/audio_mixer/gain_change_calculator.cc @@ -0,0 +1,63 @@ +/* + * Copyright (c) 2017 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 "modules/audio_mixer/gain_change_calculator.h" + +#include <math.h> + +#include <cstdlib> +#include <vector> + +#include "rtc_base/checks.h" + +namespace webrtc { + +namespace { +constexpr int16_t kReliabilityThreshold = 100; +} // namespace + +float GainChangeCalculator::CalculateGainChange( + rtc::ArrayView<const int16_t> in, + rtc::ArrayView<const int16_t> out) { + RTC_DCHECK_EQ(in.size(), out.size()); + + std::vector<float> gain(in.size()); + CalculateGain(in, out, gain); + return CalculateDifferences(gain); +} + +float GainChangeCalculator::LatestGain() const { + return last_reliable_gain_; +} + +void GainChangeCalculator::CalculateGain(rtc::ArrayView<const int16_t> in, + rtc::ArrayView<const int16_t> out, + rtc::ArrayView<float> gain) { + RTC_DCHECK_EQ(in.size(), out.size()); + RTC_DCHECK_EQ(in.size(), gain.size()); + + for (size_t i = 0; i < in.size(); ++i) { + if (std::abs(in[i]) >= kReliabilityThreshold) { + last_reliable_gain_ = out[i] / static_cast<float>(in[i]); + } + gain[i] = last_reliable_gain_; + } +} + +float GainChangeCalculator::CalculateDifferences( + rtc::ArrayView<const float> values) { + float res = 0; + for (float f : values) { + res += fabs(f - last_value_); + last_value_ = f; + } + return res; +} +} // namespace webrtc |