| // Copyright (c) 2011 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef REMOTING_HOST_CAPTURER_H_ |
| #define REMOTING_HOST_CAPTURER_H_ |
| |
| #include "base/basictypes.h" |
| #include "base/callback_old.h" |
| #include "remoting/base/capture_data.h" |
| #include "third_party/skia/include/core/SkRegion.h" |
| |
| namespace remoting { |
| |
| // A class to perform the task of capturing the image of a window. |
| // The capture action is asynchronous to allow maximum throughput. |
| // |
| // The full capture process is as follows: |
| // |
| // (1) InvalidateRects |
| // This is an optional step where regions of the screen are marked as |
| // invalid. Some platforms (Windows, for now) won't use this and will |
| // instead calculate the diff-regions later (in step (2). Other |
| // platforms (Mac) will use this to mark all the changed regions of the |
| // screen. Some limited rect-merging (e.g., to eliminate exact |
| // duplicates) may be done here. |
| // |
| // (2) CaptureInvalidRects |
| // This is where the bits for the invalid rects are packaged up and sent |
| // to the encoder. |
| // A screen capture is performed if needed. For example, Windows requires |
| // a capture to calculate the diff from the previous screen, whereas the |
| // Mac version does not. |
| // |
| // Implementation has to ensure the following guarantees: |
| // 1. Double buffering |
| // Since data can be read while another capture action is happening. |
| class Capturer { |
| public: |
| // CaptureCompletedCallback is called when the capturer has completed. |
| typedef Callback1<scoped_refptr<CaptureData> >::Type CaptureCompletedCallback; |
| |
| virtual ~Capturer() {}; |
| |
| // Create platform-specific capturer. |
| static Capturer* Create(); |
| |
| // Called when the screen configuration is changed. |
| virtual void ScreenConfigurationChanged() = 0; |
| |
| // Return the pixel format of the screen. |
| virtual media::VideoFrame::Format pixel_format() const = 0; |
| |
| // Clear out the invalid region. |
| virtual void ClearInvalidRegion() = 0; |
| |
| // Invalidate the specified region. |
| virtual void InvalidateRegion(const SkRegion& invalid_region) = 0; |
| |
| // Invalidate the entire screen, of a given size. |
| virtual void InvalidateScreen(const gfx::Size& size) = 0; |
| |
| // Invalidate the entire screen, using the size of the most recently |
| // captured screen. |
| virtual void InvalidateFullScreen() = 0; |
| |
| // Capture the screen data associated with each of the accumulated |
| // dirty region. |
| // When the capture is complete, |callback| is called even if the dirty region |
| // is empty. |
| // |
| // It is OK to call this method while another thread is reading |
| // data of the previous capture. |
| // There can be at most one concurrent read going on when this |
| // method is called. |
| virtual void CaptureInvalidRegion(CaptureCompletedCallback* callback) = 0; |
| |
| // Get the size of the most recently captured screen. |
| virtual const gfx::Size& size_most_recent() const = 0; |
| }; |
| |
| } // namespace remoting |
| |
| #endif // REMOTING_HOST_CAPTURER_H_ |