DisplayCallback Interface

interface DisplayCallback

Receives the image recognition actually ran on, so an application can show the user what the recogniser saw.

Called from the recognition thread, under the same rules as ProgressCallback: keep the work short, post to the main thread for UI, and note that throwing cancels recognition and propagates your exception to the ScanPicture.read caller unchanged.

Functions

onDisplay

abstract fun onDisplay(picture: ScanPicture): Boolean

Delivers the binarized image that recognition runs on. For large inputs the engine downscales the recognition raster, so this image may be smaller than the original.