OLD | NEW |
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | 1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
2 // Use of this source code is governed by a BSD-style license that can be | 2 // Use of this source code is governed by a BSD-style license that can be |
3 // found in the LICENSE file. | 3 // found in the LICENSE file. |
4 | 4 |
5 #ifndef MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ | 5 #ifndef MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ |
6 #define MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ | 6 #define MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ |
7 | 7 |
8 #include "base/compiler_specific.h" | 8 #include "base/compiler_specific.h" |
9 #include "base/memory/scoped_ptr.h" | 9 #include "base/memory/scoped_ptr.h" |
| 10 #include "media/video/capture/screen/shared_desktop_frame.h" |
| 11 |
| 12 namespace webrtc { |
| 13 class DesktopFrame; |
| 14 } // namespace webrtc |
10 | 15 |
11 namespace media { | 16 namespace media { |
12 | 17 |
13 class ScreenCaptureFrame; | |
14 | |
15 // Represents a queue of reusable video frames. Provides access to the 'current' | 18 // Represents a queue of reusable video frames. Provides access to the 'current' |
16 // frame - the frame that the caller is working with at the moment, and to | 19 // frame - the frame that the caller is working with at the moment, and to the |
17 // the 'previous' frame - the predecessor of the current frame swapped by | 20 // 'previous' frame - the predecessor of the current frame swapped by |
18 // DoneWithCurrentFrame() call, if any. | 21 // MoveToNextFrame() call, if any. |
19 // | 22 // |
20 // The caller is expected to (re)allocate frames if current_frame_needs_update() | 23 // The caller is expected to (re)allocate frames if current_frame() returns |
21 // is set. The caller can mark all frames in the queue for reallocation (when, | 24 // NULL. The caller can mark all frames in the queue for reallocation (when, |
22 // say, frame dimensions change). The queue records which frames need updating | 25 // say, frame dimensions change). The queue records which frames need updating |
23 // which the caller can query. | 26 // which the caller can query. |
| 27 // |
| 28 // Frame consumer is expected to never hold more than kQueueLength frames |
| 29 // created by this function and it should release the earliest one before trying |
| 30 // to capture a new frame (i.e. before MoveToNextFrame() is called). |
24 class ScreenCaptureFrameQueue { | 31 class ScreenCaptureFrameQueue { |
25 public: | 32 public: |
26 ScreenCaptureFrameQueue(); | 33 ScreenCaptureFrameQueue(); |
27 ~ScreenCaptureFrameQueue(); | 34 ~ScreenCaptureFrameQueue(); |
28 | 35 |
29 // Moves to the next frame in the queue, moving the 'current' frame to become | 36 // Moves to the next frame in the queue, moving the 'current' frame to become |
30 // the 'previous' one. | 37 // the 'previous' one. |
31 void DoneWithCurrentFrame(); | 38 void MoveToNextFrame(); |
32 | 39 |
33 // Replaces the current frame with a new one allocated by the caller. | 40 // Replaces the current frame with a new one allocated by the caller. |
34 // The existing frame (if any) is destroyed. | 41 // The existing frame (if any) is destroyed. |
35 void ReplaceCurrentFrame(scoped_ptr<ScreenCaptureFrame> frame); | 42 void ReplaceCurrentFrame(scoped_ptr<webrtc::DesktopFrame> frame); |
36 | 43 |
37 // Marks all frames obsolete and resets the previous frame pointer. No | 44 // Marks all frames obsolete and resets the previous frame pointer. No |
38 // frames are freed though as the caller can still access them. | 45 // frames are freed though as the caller can still access them. |
39 void SetAllFramesNeedUpdate(); | 46 void Reset(); |
40 | 47 |
41 ScreenCaptureFrame* current_frame() const { | 48 SharedDesktopFrame* current_frame() const { |
42 return frames_[current_].get(); | 49 return frames_[current_].get(); |
43 } | 50 } |
44 | 51 |
45 bool current_frame_needs_update() const { | 52 SharedDesktopFrame* previous_frame() const { |
46 return !current_frame() || needs_update_[current_]; | 53 return frames_[(current_ + kQueueLength - 1) % kQueueLength].get(); |
47 } | 54 } |
48 | 55 |
49 ScreenCaptureFrame* previous_frame() const { return previous_; } | |
50 | |
51 private: | 56 private: |
52 // Index of the current frame. | 57 // Index of the current frame. |
53 int current_; | 58 int current_; |
54 | 59 |
55 static const int kQueueLength = 2; | 60 static const int kQueueLength = 2; |
56 scoped_ptr<ScreenCaptureFrame> frames_[kQueueLength]; | 61 scoped_ptr<SharedDesktopFrame> frames_[kQueueLength]; |
57 | |
58 // True if the corresponding frame needs to be re-allocated. | |
59 bool needs_update_[kQueueLength]; | |
60 | |
61 // Points to the previous frame if any. | |
62 ScreenCaptureFrame* previous_; | |
63 | 62 |
64 DISALLOW_COPY_AND_ASSIGN(ScreenCaptureFrameQueue); | 63 DISALLOW_COPY_AND_ASSIGN(ScreenCaptureFrameQueue); |
65 }; | 64 }; |
66 | 65 |
67 } // namespace media | 66 } // namespace media |
68 | 67 |
69 #endif // MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ | 68 #endif // MEDIA_VIDEO_CAPTURE_SCREEN_SCREEN_CAPTURE_FRAME_QUEUE_H_ |
OLD | NEW |