Revert of Moved ring-buffer related files from common_audio to audio_processing

webrtc/common_audio/lapped_transform.cc

Index: webrtc/common_audio/lapped_transform.cc
diff --git a/webrtc/common_audio/lapped_transform.cc b/webrtc/common_audio/lapped_transform.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0edf586d78357b4ade2c94aaf48b96207f4c6825
--- /dev/null
+++ b/webrtc/common_audio/lapped_transform.cc
@@ -0,0 +1,102 @@
+/*
+ *  Copyright (c) 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 "webrtc/common_audio/lapped_transform.h"
+
+#include <algorithm>
+#include <cstdlib>
+#include <cstring>
+
+#include "webrtc/base/checks.h"
+#include "webrtc/common_audio/real_fourier.h"
+
+namespace webrtc {
+
+void LappedTransform::BlockThunk::ProcessBlock(const float* const* input,
+                                               size_t num_frames,
+                                               size_t num_input_channels,
+                                               size_t num_output_channels,
+                                               float* const* output) {
+  RTC_CHECK_EQ(num_input_channels, parent_->num_in_channels_);
+  RTC_CHECK_EQ(num_output_channels, parent_->num_out_channels_);
+  RTC_CHECK_EQ(parent_->block_length_, num_frames);
+
+  for (size_t i = 0; i < num_input_channels; ++i) {
+    memcpy(parent_->real_buf_.Row(i), input[i],
+           num_frames * sizeof(*input[0]));
+    parent_->fft_->Forward(parent_->real_buf_.Row(i),
+                           parent_->cplx_pre_.Row(i));
+  }
+
+  size_t block_length = RealFourier::ComplexLength(
+      RealFourier::FftOrder(num_frames));
+  RTC_CHECK_EQ(parent_->cplx_length_, block_length);
+  parent_->block_processor_->ProcessAudioBlock(parent_->cplx_pre_.Array(),
+                                               num_input_channels,
+                                               parent_->cplx_length_,
+                                               num_output_channels,
+                                               parent_->cplx_post_.Array());
+
+  for (size_t i = 0; i < num_output_channels; ++i) {
+    parent_->fft_->Inverse(parent_->cplx_post_.Row(i),
+                           parent_->real_buf_.Row(i));
+    memcpy(output[i], parent_->real_buf_.Row(i),
+           num_frames * sizeof(*input[0]));
+  }
+}
+
+LappedTransform::LappedTransform(size_t num_in_channels,
+                                 size_t num_out_channels,
+                                 size_t chunk_length,
+                                 const float* window,
+                                 size_t block_length,
+                                 size_t shift_amount,
+                                 Callback* callback)
+    : blocker_callback_(this),
+      num_in_channels_(num_in_channels),
+      num_out_channels_(num_out_channels),
+      block_length_(block_length),
+      chunk_length_(chunk_length),
+      block_processor_(callback),
+      blocker_(chunk_length_,
+               block_length_,
+               num_in_channels_,
+               num_out_channels_,
+               window,
+               shift_amount,
+               &blocker_callback_),
+      fft_(rtc::ScopedToUnique(
+          RealFourier::Create(RealFourier::FftOrder(block_length_)))),
+      cplx_length_(RealFourier::ComplexLength(fft_->order())),
+      real_buf_(num_in_channels,
+                block_length_,
+                RealFourier::kFftBufferAlignment),
+      cplx_pre_(num_in_channels,
+                cplx_length_,
+                RealFourier::kFftBufferAlignment),
+      cplx_post_(num_out_channels,
+                 cplx_length_,
+                 RealFourier::kFftBufferAlignment) {
+  RTC_CHECK(num_in_channels_ > 0 && num_out_channels_ > 0);
+  RTC_CHECK_GT(block_length_, 0u);
+  RTC_CHECK_GT(chunk_length_, 0u);
+  RTC_CHECK(block_processor_);
+
+  // block_length_ power of 2?
+  RTC_CHECK_EQ(0u, block_length_ & (block_length_ - 1));
+}
+
+void LappedTransform::ProcessChunk(const float* const* in_chunk,
+                                   float* const* out_chunk) {
+  blocker_.ProcessChunk(in_chunk, chunk_length_, num_in_channels_,
+                        num_out_channels_, out_chunk);
+}
+
+}  // namespace webrtc