Finalization of the first version of EchoCanceller 3

webrtc/modules/audio_processing/aec3/output_selector.h

+/*
+ *  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.
+ */
+
+#ifndef WEBRTC_MODULES_AUDIO_PROCESSING_AEC3_OUTPUT_SELECTOR_H_
+#define WEBRTC_MODULES_AUDIO_PROCESSING_AEC3_OUTPUT_SELECTOR_H_
+
+#include "webrtc/base/array_view.h"
+#include "webrtc/base/constructormagic.h"
+
+namespace webrtc {
+
+// Performs the selection between which of the linear aec output and the
+// microphone signal should be used as the echo suppressor output.
+class OutputSelector {
+ public:
+  OutputSelector();
+  ~OutputSelector();
+
+  // Forms the most appropriate output signal.
+  void FormLinearOutput(rtc::ArrayView<const float> subtractor_output,
+                        rtc::ArrayView<float> capture);
+
+  // Returns true if the linear aec output is the one used.
+  bool UseSubtractorOutput() const { return use_subtractor_output_; }
+
+ private:
+  bool use_subtractor_output_ = false;
+  int output_change_counter_ = 0;
+  RTC_DISALLOW_COPY_AND_ASSIGN(OutputSelector);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_PROCESSING_AEC3_OUTPUT_SELECTOR_H_