Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

modules/audio_processing/aec3/render_delay_buffer.cc

@@ -0,0 +1,217 @@
+/*
+ *  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/render_delay_buffer.h"
+
+#include <string.h>
+#include <algorithm>
+
+#include "webrtc/modules/audio_processing/aec3/aec3_common.h"
+#include "webrtc/modules/audio_processing/aec3/block_processor.h"
+#include "webrtc/modules/audio_processing/aec3/decimator_by_4.h"
+#include "webrtc/modules/audio_processing/aec3/fft_data.h"
+#include "webrtc/rtc_base/checks.h"
+#include "webrtc/rtc_base/constructormagic.h"
+#include "webrtc/rtc_base/logging.h"
+
+namespace webrtc {
+namespace {
+
+class ApiCallJitterBuffer {
+ public:
+  explicit ApiCallJitterBuffer(size_t num_bands) {
+    buffer_.fill(std::vector<std::vector<float>>(
+        num_bands, std::vector<float>(kBlockSize, 0.f)));
+  }
+
+  ~ApiCallJitterBuffer() = default;
+
+  void Reset() {
+    size_ = 0;
+    last_insert_index_ = 0;
+  }
+
+  void Insert(const std::vector<std::vector<float>>& block) {
+    RTC_DCHECK_LT(size_, buffer_.size());
+    last_insert_index_ = (last_insert_index_ + 1) % buffer_.size();
+    RTC_DCHECK_EQ(buffer_[last_insert_index_].size(), block.size());
+    RTC_DCHECK_EQ(buffer_[last_insert_index_][0].size(), block[0].size());
+    for (size_t k = 0; k < block.size(); ++k) {
+      std::copy(block[k].begin(), block[k].end(),
+                buffer_[last_insert_index_][k].begin());
+    }
+    ++size_;
+  }
+
+  void Remove(std::vector<std::vector<float>>* block) {
+    RTC_DCHECK_LT(0, size_);
+    --size_;
+    const size_t extract_index =
+        (last_insert_index_ - size_ + buffer_.size()) % buffer_.size();
+    for (size_t k = 0; k < block->size(); ++k) {
+      std::copy(buffer_[extract_index][k].begin(),
+                buffer_[extract_index][k].end(), (*block)[k].begin());
+    }
+  }
+
+  size_t Size() const { return size_; }
+  bool Full() const { return size_ >= (buffer_.size()); }
+  bool Empty() const { return size_ == 0; }
+
+ private:
+  std::array<std::vector<std::vector<float>>, kMaxApiCallsJitterBlocks> buffer_;
+  size_t size_ = 0;
+  int last_insert_index_ = 0;
+};
+
+class RenderDelayBufferImpl final : public RenderDelayBuffer {
+ public:
+  explicit RenderDelayBufferImpl(size_t num_bands);
+  ~RenderDelayBufferImpl() override;
+
+  void Reset() override;
+  bool Insert(const std::vector<std::vector<float>>& block) override;
+  bool UpdateBuffers() override;
+  void SetDelay(size_t delay) override;
+  size_t Delay() const override { return delay_; }
+
+  const RenderBuffer& GetRenderBuffer() const override { return fft_buffer_; }
+
+  const DownsampledRenderBuffer& GetDownsampledRenderBuffer() const override {
+    return downsampled_render_buffer_;
+  }
+
+ private:
+  const Aec3Optimization optimization_;
+  std::array<std::vector<std::vector<float>>, kRenderDelayBufferSize> buffer_;
+  size_t delay_ = 0;
+  size_t last_insert_index_ = 0;
+  RenderBuffer fft_buffer_;
+  DownsampledRenderBuffer downsampled_render_buffer_;
+  DecimatorBy4 render_decimator_;
+  ApiCallJitterBuffer api_call_jitter_buffer_;
+  const std::vector<std::vector<float>> zero_block_;
+  RTC_DISALLOW_IMPLICIT_CONSTRUCTORS(RenderDelayBufferImpl);
+};
+
+RenderDelayBufferImpl::RenderDelayBufferImpl(size_t num_bands)
+    : optimization_(DetectOptimization()),
+      fft_buffer_(
+          optimization_,
+          num_bands,
+          std::max(kResidualEchoPowerRenderWindowSize, kAdaptiveFilterLength),
+          std::vector<size_t>(1, kAdaptiveFilterLength)),
+      api_call_jitter_buffer_(num_bands),
+      zero_block_(num_bands, std::vector<float>(kBlockSize, 0.f)) {
+  buffer_.fill(std::vector<std::vector<float>>(
+      num_bands, std::vector<float>(kBlockSize, 0.f)));
+
+  RTC_DCHECK_LT(buffer_.size(), downsampled_render_buffer_.buffer.size());
+}
+
+RenderDelayBufferImpl::~RenderDelayBufferImpl() = default;
+
+void RenderDelayBufferImpl::Reset() {
+  // Empty all data in the buffers.
+  delay_ = 0;
+  last_insert_index_ = 0;
+  downsampled_render_buffer_.position = 0;
+  downsampled_render_buffer_.buffer.fill(0.f);
+  fft_buffer_.Clear();
+  api_call_jitter_buffer_.Reset();
+  for (auto& c : buffer_) {
+    for (auto& b : c) {
+      std::fill(b.begin(), b.end(), 0.f);
+    }
+  }
+}
+
+bool RenderDelayBufferImpl::Insert(
+    const std::vector<std::vector<float>>& block) {
+  RTC_DCHECK_EQ(block.size(), buffer_[0].size());
+  RTC_DCHECK_EQ(block[0].size(), buffer_[0][0].size());
+
+  if (api_call_jitter_buffer_.Full()) {
+    // Report buffer overrun and let the caller handle the overrun.
+    return false;
+  }
+  api_call_jitter_buffer_.Insert(block);
+
+  return true;
+}
+
+bool RenderDelayBufferImpl::UpdateBuffers() {
+  bool underrun = true;
+  // Update the buffers with a new block if such is available, otherwise insert
+  // a block of silence.
+  if (api_call_jitter_buffer_.Size() > 0) {
+    last_insert_index_ = (last_insert_index_ + 1) % buffer_.size();
+    api_call_jitter_buffer_.Remove(&buffer_[last_insert_index_]);
+    underrun = false;
+  }
+
+  downsampled_render_buffer_.position =
+      (downsampled_render_buffer_.position - kSubBlockSize +
+       downsampled_render_buffer_.buffer.size()) %
+      downsampled_render_buffer_.buffer.size();
+
+  std::array<float, kSubBlockSize> render_downsampled;
+  if (underrun) {
+    render_decimator_.Decimate(zero_block_[0], render_downsampled);
+  } else {
+    render_decimator_.Decimate(buffer_[last_insert_index_][0],
+                               render_downsampled);
+  }
+  std::copy(render_downsampled.rbegin(), render_downsampled.rend(),
+            downsampled_render_buffer_.buffer.begin() +
+                downsampled_render_buffer_.position);
+
+  if (underrun) {
+    fft_buffer_.Insert(zero_block_);
+  } else {
+    fft_buffer_.Insert(buffer_[(last_insert_index_ - delay_ + buffer_.size()) %
+                               buffer_.size()]);
+  }
+  return !underrun;
+}
+
+void RenderDelayBufferImpl::SetDelay(size_t delay) {
+  if (delay_ == delay) {
+    return;
+  }
+
+  // If there is a new delay set, clear the fft buffer.
+  fft_buffer_.Clear();
+
+  if ((buffer_.size() - 1) < delay) {
+    // If the desired delay is larger than the delay buffer, shorten the delay
+    // buffer size to achieve the desired alignment with the available buffer
+    // size.
+    downsampled_render_buffer_.position =
+        (downsampled_render_buffer_.position +
+         kSubBlockSize * (delay - (buffer_.size() - 1))) %
+        downsampled_render_buffer_.buffer.size();
+
+    last_insert_index_ =
+        (last_insert_index_ - (delay - (buffer_.size() - 1)) + buffer_.size()) %
+        buffer_.size();
+    delay_ = buffer_.size() - 1;
+  } else {
+    delay_ = delay;
+  }
+}
+
+}  // namespace
+
+RenderDelayBuffer* RenderDelayBuffer::Create(size_t num_bands) {
+  return new RenderDelayBufferImpl(num_bands);
+}
+
+}  // namespace webrtc