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

webrtc/modules/audio_processing/utility/blocker.cc

-/*
- *  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/modules/audio_processing/utility/blocker.h"
-
-#include <string.h>
-
-#include "webrtc/base/checks.h"
-
-namespace {
-
-// Adds |a| and |b| frame by frame into |result| (basically matrix addition).
-void AddFrames(const float* const* a,
-               size_t a_start_index,
-               const float* const* b,
-               int b_start_index,
-               size_t num_frames,
-               size_t num_channels,
-               float* const* result,
-               size_t result_start_index) {
-  for (size_t i = 0; i < num_channels; ++i) {
-    for (size_t j = 0; j < num_frames; ++j) {
-      result[i][j + result_start_index] =
-          a[i][j + a_start_index] + b[i][j + b_start_index];
-    }
-  }
-}
-
-// Copies |src| into |dst| channel by channel.
-void CopyFrames(const float* const* src,
-                size_t src_start_index,
-                size_t num_frames,
-                size_t num_channels,
-                float* const* dst,
-                size_t dst_start_index) {
-  for (size_t i = 0; i < num_channels; ++i) {
-    memcpy(&dst[i][dst_start_index],
-           &src[i][src_start_index],
-           num_frames * sizeof(dst[i][dst_start_index]));
-  }
-}
-
-// Moves |src| into |dst| channel by channel.
-void MoveFrames(const float* const* src,
-                size_t src_start_index,
-                size_t num_frames,
-                size_t num_channels,
-                float* const* dst,
-                size_t dst_start_index) {
-  for (size_t i = 0; i < num_channels; ++i) {
-    memmove(&dst[i][dst_start_index],
-            &src[i][src_start_index],
-            num_frames * sizeof(dst[i][dst_start_index]));
-  }
-}
-
-void ZeroOut(float* const* buffer,
-             size_t starting_idx,
-             size_t num_frames,
-             size_t num_channels) {
-  for (size_t i = 0; i < num_channels; ++i) {
-    memset(&buffer[i][starting_idx], 0,
-           num_frames * sizeof(buffer[i][starting_idx]));
-  }
-}
-
-// Pointwise multiplies each channel of |frames| with |window|. Results are
-// stored in |frames|.
-void ApplyWindow(const float* window,
-                 size_t num_frames,
-                 size_t num_channels,
-                 float* const* frames) {
-  for (size_t i = 0; i < num_channels; ++i) {
-    for (size_t j = 0; j < num_frames; ++j) {
-      frames[i][j] = frames[i][j] * window[j];
-    }
-  }
-}
-
-size_t gcd(size_t a, size_t b) {
-  size_t tmp;
-  while (b) {
-     tmp = a;
-     a = b;
-     b = tmp % b;
-  }
-  return a;
-}
-
-}  // namespace
-
-namespace webrtc {
-
-Blocker::Blocker(size_t chunk_size,
-                 size_t block_size,
-                 size_t num_input_channels,
-                 size_t num_output_channels,
-                 const float* window,
-                 size_t shift_amount,
-                 BlockerCallback* callback)
-    : chunk_size_(chunk_size),
-      block_size_(block_size),
-      num_input_channels_(num_input_channels),
-      num_output_channels_(num_output_channels),
-      initial_delay_(block_size_ - gcd(chunk_size, shift_amount)),
-      frame_offset_(0),
-      input_buffer_(num_input_channels_, chunk_size_ + initial_delay_),
-      output_buffer_(chunk_size_ + initial_delay_, num_output_channels_),
-      input_block_(block_size_, num_input_channels_),
-      output_block_(block_size_, num_output_channels_),
-      window_(new float[block_size_]),
-      shift_amount_(shift_amount),
-      callback_(callback) {
-  RTC_CHECK_LE(num_output_channels_, num_input_channels_);
-  RTC_CHECK_LE(shift_amount_, block_size_);
-
-  memcpy(window_.get(), window, block_size_ * sizeof(*window_.get()));
-  input_buffer_.MoveReadPositionBackward(initial_delay_);
-}
-
-// When block_size < chunk_size the input and output buffers look like this:
-//
-//                      delay*             chunk_size    chunk_size + delay*
-//  buffer: <-------------|---------------------|---------------|>
-//                _a_              _b_                 _c_
-//
-// On each call to ProcessChunk():
-// 1. New input gets read into sections _b_ and _c_ of the input buffer.
-// 2. We block starting from frame_offset.
-// 3. We block until we reach a block |bl| that doesn't contain any frames
-//    from sections _a_ or _b_ of the input buffer.
-// 4. We window the current block, fire the callback for processing, window
-//    again, and overlap/add to the output buffer.
-// 5. We copy sections _a_ and _b_ of the output buffer into output.
-// 6. For both the input and the output buffers, we copy section _c_ into
-//    section _a_.
-// 7. We set the new frame_offset to be the difference between the first frame
-//    of |bl| and the border between sections _b_ and _c_.
-//
-// When block_size > chunk_size the input and output buffers look like this:
-//
-//                   chunk_size               delay*       chunk_size + delay*
-//  buffer: <-------------|---------------------|---------------|>
-//                _a_              _b_                 _c_
-//
-// On each call to ProcessChunk():
-// The procedure is the same as above, except for:
-// 1. New input gets read into section _c_ of the input buffer.
-// 3. We block until we reach a block |bl| that doesn't contain any frames
-//    from section _a_ of the input buffer.
-// 5. We copy section _a_ of the output buffer into output.
-// 6. For both the input and the output buffers, we copy sections _b_ and _c_
-//    into section _a_ and _b_.
-// 7. We set the new frame_offset to be the difference between the first frame
-//    of |bl| and the border between sections _a_ and _b_.
-//
-// * delay here refers to inintial_delay_
-//
-// TODO(claguna): Look at using ring buffers to eliminate some copies.
-void Blocker::ProcessChunk(const float* const* input,
-                           size_t chunk_size,
-                           size_t num_input_channels,
-                           size_t num_output_channels,
-                           float* const* output) {
-  RTC_CHECK_EQ(chunk_size, chunk_size_);
-  RTC_CHECK_EQ(num_input_channels, num_input_channels_);
-  RTC_CHECK_EQ(num_output_channels, num_output_channels_);
-
-  input_buffer_.Write(input, num_input_channels, chunk_size_);
-  size_t first_frame_in_block = frame_offset_;
-
-  // Loop through blocks.
-  while (first_frame_in_block < chunk_size_) {
-    input_buffer_.Read(input_block_.channels(), num_input_channels,
-                       block_size_);
-    input_buffer_.MoveReadPositionBackward(block_size_ - shift_amount_);
-
-    ApplyWindow(window_.get(),
-                block_size_,
-                num_input_channels_,
-                input_block_.channels());
-    callback_->ProcessBlock(input_block_.channels(),
-                            block_size_,
-                            num_input_channels_,
-                            num_output_channels_,
-                            output_block_.channels());
-    ApplyWindow(window_.get(),
-                block_size_,
-                num_output_channels_,
-                output_block_.channels());
-
-    AddFrames(output_buffer_.channels(),
-              first_frame_in_block,
-              output_block_.channels(),
-              0,
-              block_size_,
-              num_output_channels_,
-              output_buffer_.channels(),
-              first_frame_in_block);
-
-    first_frame_in_block += shift_amount_;
-  }
-
-  // Copy output buffer to output
-  CopyFrames(output_buffer_.channels(),
-             0,
-             chunk_size_,
-             num_output_channels_,
-             output,
-             0);
-
-  // Copy output buffer [chunk_size_, chunk_size_ + initial_delay]
-  // to output buffer [0, initial_delay], zero the rest.
-  MoveFrames(output_buffer_.channels(),
-             chunk_size,
-             initial_delay_,
-             num_output_channels_,
-             output_buffer_.channels(),
-             0);
-  ZeroOut(output_buffer_.channels(),
-          initial_delay_,
-          chunk_size_,
-          num_output_channels_);
-
-  // Calculate new starting frames.
-  frame_offset_ = first_frame_in_block - chunk_size_;
-}
-
-}  // namespace webrtc