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The element allows monitoring the output of any video capturing device, e.g. webcam, on the status screen in EventIDE.

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Description
Snapshots
Practical Use
Technique 1
Element actions aligned with different epochs of the parent event
Notes
Properties
Generic Properties

Description ¶

Short description

Snapshot 1

Snapshot 2

Add new Webcam element to any event in your experiment
Click on the Webcam element and select a video device from the device list in the property grid
Add a proxy variable to the Video Output property of the Webcam element
Create a XAML ContentControl on the status screen and set its binding to the VideoOutput proxy variable:

 // you can place the content control inside of any parent container
<ContentControl Width="640" Height="480" Content='{Binding VideoOutput}'/>

Make sure that camera working and run an experiment. The video output will be rendered scaled to the area of the Content Control on the Status Screen

Epoche	Actions
Initialized	The camera starts capturing video
Rendered
Activating
Activated
Running	The camera output is captured and rendered via the Video Output property, if the latter is bound to the status screen
Deactivated
Deinitialized	The camera stops capturing video

You can not share output of the same camera among multiple Webcam elements. However, you may have multiple cameras linked to multiple Webcam elements.
Be careful in using the Webcam element in experiments that require accurate timing. Video capturing is hardware-accelerated on the most computers but a high processor load still can be induced, which may potentially disrupt timing in an experiment. We suggest to always double check timing accuracy while the Webcam element is engaged.
If you have Webcam element, whose Video Output is not bound to the status Screen, there is no performance costs for rendering. However, video capturing is still performed by a computer in this case, which can cause a slow down.

Name	Description	Constraints	Value Type
Settings
Video Device	Defines a video device for capturing	Design Time..	String
Device Settings	Opens a window with OS settings of the selected video device.	Design Time..
Custom Settings
Use Custom Settings	Define whether custom frame size and framerate are used in capturing video. Using the custom settings is only possible, if it's supported by the selected video device. Otherwise, the device's default settings will be are applied.	Design Time..	Boolean
Resolution	Define the resolution of captured video. The video frames are automatically stretched to any destination size in rendering, however, a large resolution improves rendering quality with some cost in performance.	Design Time..	clSize
Frame Rate	Define the framerate of video capturing, in frames per second	Design Time..	Int32
Runtime Status
Video Output	Returns a live XAML control that renders the captured video output. The control can be used for data binding to the Content property of the XAML ContentControl element, e.g. . The ContentControl can be added to the status screen or to the XAML Layout element.	Fill it	System.Windows.UIElement
Actual Settings	Returns the actual resolution and framerate of video capture. The property is updated on every experiment run.	FORMATTER ERROR (Snippet Not Found)	String

+=== Properties inherited from clElement === Inherited properties of clElement

Name	Description	Constraints	Value Type
Control
Is Enabled	If set to false the element is completely omitted when the experiment is run.	Design Time..	Boolean
Title	Title of the element.	Design Time..	String