Remove differ from ScreenCapturer implementations

webrtc/modules/desktop_capture/differ.h

-/*
- *  Copyright (c) 2013 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_DESKTOP_CAPTURE_DIFFER_H_
-#define WEBRTC_MODULES_DESKTOP_CAPTURE_DIFFER_H_
-
-#include <memory>
-#include <vector>
-
-#include "webrtc/base/constructormagic.h"
-#include "webrtc/modules/desktop_capture/desktop_region.h"
-
-namespace webrtc {
-
-// TODO(sergeyu): Simplify differ now that we are working with DesktopRegion.
-// diff_info_ should no longer be needed, as we can put our data directly into
-// the region that we are calculating.
-// http://crbug.com/92379
-// TODO(sergeyu): Rename this class to something more sensible, e.g.
-// ScreenCaptureFrameDifferencer.
-class Differ {
- public:
-  // Create a differ that operates on bitmaps with the specified width, height
-  // and bytes_per_pixel.
-  Differ(int width, int height, int bytes_per_pixel, int stride);
-  ~Differ();
-
-  int width() { return width_; }
-  int height() { return height_; }
-  int bytes_per_pixel() { return bytes_per_pixel_; }
-  int bytes_per_row() { return bytes_per_row_; }
-
-  // Given the previous and current screen buffer, calculate the dirty region
-  // that encloses all of the changed pixels in the new screen.
-  void CalcDirtyRegion(const uint8_t* prev_buffer, const uint8_t* curr_buffer,
-                       DesktopRegion* region);
-
- private:
-  // Allow tests to access our private parts.
-  friend class DifferTest;
-
-  // Identify all of the blocks that contain changed pixels.
-  void MarkDirtyBlocks(const uint8_t* prev_buffer, const uint8_t* curr_buffer);
-
-  // After the dirty blocks have been identified, this routine merges adjacent
-  // blocks into a region.
-  // The goal is to minimize the region that covers the dirty blocks.
-  void MergeBlocks(DesktopRegion* region);
-
-  // Checks whether the upper-left portions of the buffers are equal. The size
-  // of the portion to check is specified by the |width| and |height| values.
-  // Note that if we force the capturer to always return images whose width and
-  // height are multiples of kBlockSize, then this will never be called.
-  bool PartialBlocksEqual(const uint8_t* prev_buffer,
-                          const uint8_t* curr_buffer,
-                          int stride,
-                          int width, int height);
-
-  // Dimensions of screen.
-  int width_;
-  int height_;
-
-  // Number of bytes for each pixel in source and dest bitmap.
-  // (Yes, they must match.)
-  int bytes_per_pixel_;
-
-  // Number of bytes in each row of the image (AKA: stride).
-  int bytes_per_row_;
-
-  // Diff information for each block in the image.
-  std::unique_ptr<bool[]> diff_info_;
-
-  // Dimensions and total size of diff info array.
-  int diff_info_width_;
-  int diff_info_height_;
-  int diff_info_size_;
-
-  RTC_DISALLOW_COPY_AND_ASSIGN(Differ);
-};
-
-}  // namespace webrtc
-
-#endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_DIFFER_H_