Hi David,
In order to use the capture and playback functionality of our DeckLink devices, you will need to use Blackmagic's API. Access to this functionality is available through our free Desktop Video SDK.
Documentation and sample applications to get you started can be found in the SDK Download.
The API handles the RAW capture and playback of video frames through the card itself.
However, Apple's AVFoundation framework is used for our Mac OS X samples to provide file capture/playback functionality. You may find that much of your AVFoundation is still functional with our SDK.
Depending on what you're trying to achieve, I would recommend taking a look at the File Capture or CapturePreview sample applications.
You can download our SDK at our Developer Website:
https://www.blackmagicdesign.com/au/dev ... d-playback