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isvalid

17-55

isvalid

Determine whether image acquisition object is associated with image acquisition device

Syntax

bool = isvalid(obj)

Description

bool = isvalid(obj) returns true if the video input object obj is valid, otherwise

false. An object is an invalid image acquisition object if it is no longer associated with

any hardware; that is, the object was deleted using the delete function. If this is the

case, obj should be cleared from the workspace.

If obj is an array of video input objects, bool is a logical array where each element

in bool represents the corresponding element in obj. If an object in obj is valid, the

isvalid function sets the corresponding element in bool to true, otherwise false.