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Live View

This page shows how to obtain live view of connected camera devices using RICOH Camera USB SDK.

For devices that support to live view, please refer to Appendix.

Contents

The following classes are used when you obtain live view:

CameraEventListener

  • The CameraEventListener class is a event listener which receives notifications from camera devices.

CameraDevice

  • The CameraDevice class represents a camera device.
  • This class includes properties and methods for obtaining camera information and operating camera device.

Set up Live View Event

To start live view, override the virtual method liveViewFrameUpdated included in the CameraEventListener class with the user-defined derived class. JPEG data is streamed all the time, which keeps calling liveViewFrameUpdated.

class UserEventListener : public CameraEventListener {
public:
    void liveViewFrameUpdated(const std::shared_ptr<const CameraDevice>& sender,
                              const std::shared_ptr<const unsigned char>& liveViewFrame,
                              uint64_t frameSize) override
    {
        std::cout << "Live View Frame Updated. Frame Size: " << frameSize
                  << std::endl;
    }
};

Start Live View

Use the startLiveView to start live view.

std::shared_ptr<CameraEventListener> userEventListener =
    std::make_shared<UserEventListener>();
cameraDevice->addEventListener(userEventListener);
Response response = cameraDevice->startLiveView();

Adjust Focus

If you want to adjust the focus while checking the live view, use the focus method with the adjustment argument. Argument represents the moving direction and moving amount of the focus. If the argument is positive, the focus moves forward. If the argument is negative, the focus moves backward.

int adjustment = 100;
Response response = cameraDevice->focus(adjustment);

Focus at Specified Position

If you want focus at specified position while checking the live view, use the focus method with the focusPoint argument.

The position that can be specified varies depending on the devices and setting conditions, and information can be get from the Live View Specification.

Point focusPoint;
focusPoint.x = 0.2;
focusPoint.y = 0.5;
Response response = cameraDevice->focus(focusPoint);

Capture with Focusing at Specified Position

If you want to capture with focusing at specified position while checking the live view, use the startCapture method with the focusPoint argument.

The position that can be specified varies depending on the devices and setting conditions, and information can be get from the Live View Specification.

Point focusPoint;
focusPoint.x = 0.2;
focusPoint.y = 0.5;
Response response = cameraDevice->startCapture(focusPoint);

Stop Live View

Use the stopLiveView to stop live view.

Response response = cameraDevice->stopLiveView();

See Also