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Device Access and User Interface Classes

There are two classes in this particular group: QTCaptureDevice and QTCaptureView.

If you’re working with QTCaptureDevice objects, your application can read any number of extended attributes available to this class, using the deviceAttributes and attributeForKey: methods. Beyond that, you can use key-value coding to get and set attributes. If you wish to observe changes for a given attribute, you can add a key-value observer where the key path is the attribute key. Note that you cannot create instances of QTCaptureDevice directly.

You can use the methods available in the QTCaptureView class, which is a subclass of NSView, to preview video that is being processed by an instance of QTCaptureSession. The class creates and maintains its own QTCaptureVideoPreviewOutput to gather the preview video you need from the capture session.

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