Adding second layer of the echo canceller 3 functionality.

webrtc/modules/audio_processing/aec3/echo_remover.cc

Index: webrtc/modules/audio_processing/aec3/echo_remover.cc
diff --git a/webrtc/modules/audio_processing/aec3/echo_remover.cc b/webrtc/modules/audio_processing/aec3/echo_remover.cc
new file mode 100644
index 0000000000000000000000000000000000000000..2ae5525b4a7510a46a7f7701bf3d6e39404e9f63
--- /dev/null
+++ b/webrtc/modules/audio_processing/aec3/echo_remover.cc
@@ -0,0 +1,74 @@
+/*
+ *  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 "webrtc/modules/audio_processing/aec3/echo_remover.h"
+
+#include <algorithm>
+#include <vector>
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/base/checks.h"
+#include "webrtc/base/optional.h"
+#include "webrtc/modules/audio_processing/aec3/aec3_constants.h"
+
+namespace webrtc {
+
+namespace {
+class EchoRemoverImpl final : public EchoRemover {
+ public:
+  explicit EchoRemoverImpl(int sample_rate_hz);
+  ~EchoRemoverImpl() override;
+
+  void ProcessBlock(const rtc::Optional<size_t>& echo_path_delay_samples,
+                    const EchoPathVariability& echo_path_variability,
+                    bool capture_signal_saturation,
+                    const std::vector<std::vector<float>>& render,
+                    std::vector<std::vector<float>>* capture) override;
+
+  void UpdateEchoLeakageStatus(bool leakage_detected) override;
+
+ private:
+  const int sample_rate_hz_;
+
+  RTC_DISALLOW_COPY_AND_ASSIGN(EchoRemoverImpl);
+};
+
+// TODO(peah): Add functionality.
+EchoRemoverImpl::EchoRemoverImpl(int sample_rate_hz)
+    : sample_rate_hz_(sample_rate_hz) {
+  RTC_DCHECK(sample_rate_hz == 8000 || sample_rate_hz == 16000 ||
+             sample_rate_hz == 32000 || sample_rate_hz == 48000);
+}
+
+EchoRemoverImpl::~EchoRemoverImpl() = default;
+
+// TODO(peah): Add functionality.
+void EchoRemoverImpl::ProcessBlock(
+    const rtc::Optional<size_t>& echo_path_delay_samples,
+    const EchoPathVariability& echo_path_variability,
+    bool capture_signal_saturation,
+    const std::vector<std::vector<float>>& render,
+    std::vector<std::vector<float>>* capture) {
+  RTC_DCHECK(capture);
+  RTC_DCHECK_EQ(render.size(), NumBandsForRate(sample_rate_hz_));
+  RTC_DCHECK_EQ(capture->size(), NumBandsForRate(sample_rate_hz_));
+  RTC_DCHECK_EQ(render[0].size(), kBlockSize);
+  RTC_DCHECK_EQ((*capture)[0].size(), kBlockSize);
+}
+
+// TODO(peah): Add functionality.
+void EchoRemoverImpl::UpdateEchoLeakageStatus(bool leakage_detected) {}
+
+}  // namespace
+
+EchoRemover* EchoRemover::Create(int sample_rate_hz) {
+  return new EchoRemoverImpl(sample_rate_hz);
+}
+
+}  // namespace webrtc