Performance Considerations

This section describes some of the factors that affect the amount of time required by the tool to compute a sharpness score.

In image difference mode, the amount of time required to compute a sharpness score for a particular image is affected by the following factors:

In auto-correlation mode, the amount of time required to compute a sharpness score is affected by the size of the input image (larger images require more time).
In general, for large image offsets, image difference mode is faster than auto-correlation mode for a given image size. If, however, you need to determine the sharpness of an image with mostly small features, auto-correlation mode may be faster.
For most images, band pass filtering mode is a slower procedure than other modes.
In gradient energy mode if you specify a lowPassSmoothing parameter value greater than zero, the tool will run slower.