Add a ChromeOS implementation of VideoCaptureDevice

media/video/capture/linux/video_capture_device_linux.h

 // Copyright (c) 2012 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.
 
 // Linux specific implementation of VideoCaptureDevice.
 // V4L2 is used for capturing. V4L2 does not provide its own thread for
 // capturing so this implementation uses a Chromium thread for fetching frames
 // from V4L2.
 
 #ifndef MEDIA_VIDEO_CAPTURE_LINUX_VIDEO_CAPTURE_DEVICE_LINUX_H_
@@ skipping 17 matching lines @@
 
   explicit VideoCaptureDeviceLinux(const Name& device_name);
   virtual ~VideoCaptureDeviceLinux();
 
   // VideoCaptureDevice implementation.
   virtual void AllocateAndStart(const VideoCaptureParams& params,
                                 scoped_ptr<Client> client) OVERRIDE;
 
   virtual void StopAndDeAllocate() OVERRIDE;
 
+ protected:
+  void SetRotation(int rotation);
+
+  // Once |v4l2_thread_| is started, only called on that thread.
+  void SetRotationOnV4L2Thread(int rotation);
+
  private:
   enum InternalState {
     kIdle,  // The device driver is opened but camera is not in use.
     kCapturing,  // Video is being captured.
     kError  // Error accessing HW functions.
             // User needs to recover by destroying the object.
   };
 
   // Buffers used to receive video frames from with v4l2.
   struct Buffer {
@@ skipping 17 matching lines @@
   InternalState state_;
   scoped_ptr<VideoCaptureDevice::Client> client_;
   Name device_name_;
   base::ScopedFD device_fd_;  // File descriptor for the opened camera device.
   base::Thread v4l2_thread_;  // Thread used for reading data from the device.
   Buffer* buffer_pool_;
   int buffer_pool_size_;  // Number of allocated buffers.
   int timeout_count_;
   VideoCaptureFormat capture_format_;
 
+  // Clockwise rotation in degrees.  This value should be 0, 90, 180, or 270.
+  // This is only used on |v4l2_thread_| when it is running, or the constructor
+  // thread otherwise.
+  int rotation_;
+
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceLinux);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_VIDEO_CAPTURE_LINUX_VIDEO_CAPTURE_DEVICE_LINUX_H_