Core Image filters are organized into categories internally. A filter can belong to more than one category; for example, a color effect filter like Sepia Tone belongs to six categories, including
CICategoryBuiltIn. These categories are useful to the developer to determine what Core Image filters are available for a desired task, and can be used as in the sample app to allow the user to browse and select available filters.
In the sample app, when a user taps the Add Filter button, a popover segue is initiated. This segue will initialize a
UINavigationController, and an instance ...