kdu_image_in::destroy

Instances of the kdu_image_in class are only interfaces to the underlying image reading object. As such, they may be copied at will. To avoid the underlying object being destroyed when an interface to it goes out of scope, we provide an explicit destruction function. This is simpler and more obvious, if slightly more dangerous than reference counting.

Generates a warning message if one or more image lines were not consumed from any component.