>Psychtoolbox>PsychVideoCapture

Return deviceIndex of a specified camera, one that matches given criteria.

[deviceIndex, dev] = PsychGetCamIdForSpec([className][, inputNameOrPort][, instance][, engineId]);

Searches for video sources which match given criteria. A handle to the
first source that satisfies the criteria is returned in argument
‘deviceIndex’ - You can open a connection to the source via
Screen(‘OpenVideoCapture’, windowPtr, deviceIndex, …);

The 2nd optional return argument contains the complete ‘dev’ice
description struct, as returned by Screen().

Returns empty variables if no match can be made.

Optional criteria:

‘className’ Index or name of video input device class: Default is to
accept any class. This matches against the ‘ClassName’ property of the
list returned by Screen(‘VideoCaptureDevices’).

‘inputNameOrPort’ selects the i’th input device of a matching class if an
index is given (zero-based), or a specific named device, e.g., ‘iSight’
for the builtin iSight camera of Apple hardware.

‘instance’ If multiple devices match, take the i’th device where i ==
instance. By default, the first device (instance == 0) is assigned.

‘engineId’ Enumerate for video capture engine ‘engineId’. By default, the
default videocapture engine is used.