Capturing can be thought of as the input phase of the standard media processing model. A capture device might deliver multiple media streams. For example, a video camera might deliver both audio and video. These streams might be captured and manipulated separately or combined into a single, multiplexed stream that contains both an audio track and a video track. Similarly, capturing a TV broadcast requires a TV tuner and an appropriate video capture card.
Most systems provide a query mechanism to find out what capture devices are available.
Capture devices can be characterized as either push or pull sources. The format of a captured media stream depends on the processing performed by the capture device. Some devices do very little processing and deliver raw, uncompressed data. Other capture devices might deliver the data in a compressed format. Capture Controls Controls are sometimes provided to enable the user to manage the capture process.