|  | /* | 
|  | *  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_BLOCK_H_ | 
|  | #define WEBRTC_MODULES_DESKTOP_CAPTURE_DIFFER_BLOCK_H_ | 
|  |  | 
|  | #include "webrtc/typedefs.h" | 
|  |  | 
|  | namespace webrtc { | 
|  |  | 
|  | // Size (in pixels) of each square block used for diffing. This must be a | 
|  | // multiple of sizeof(uint64)/8. | 
|  | const int kBlockSize = 32; | 
|  |  | 
|  | // Format: BGRA 32 bit. | 
|  | const int kBytesPerPixel = 4; | 
|  |  | 
|  | // Low level functions to compare 2 blocks of pixels. Zero means the blocks | 
|  | // are identical. One - the blocks are different. | 
|  | int BlockDifference(const uint8_t* image1, const uint8_t* image2, int stride); | 
|  |  | 
|  | }  // namespace webrtc | 
|  |  | 
|  | #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_DIFFER_BLOCK_H_ |