Unsharp Filter Characteristics Options

[Derek Wright]

Peter

Please will you describe the characteristics of the Unsharp filter - comparing it to the filter in say Gimp which has three settings Radius, Amount and Threshold. By adjusting the settings especially the Radius setting one can alter the strength of the filter.

What is the equivalent PMview settings.

Is it possible for the user to create a user defined unsharp filter and or do you have any plans to add a user customisable unsharp filter.

Thanks for PMVIEW

[Peter]

I don't know Gimp, but my guess is that the radius is probably the size of the filter matrix, say 3x3, 5x5, 7x7, 9x9. The amount is the strength of the weights in the filter.

My gut react is that you should be able to create the same filter with the "User Defined Filter" dialog, unless Gimp has added something special to its unsharp filter. (Note that you can create arbitrarily large filters with PMView if you use a text editor. The built-in filter editor only handles up to 7x7 filters).

PMView uses a 5x5 unsharp filter if I recall correcly. I need to get back to you with the filter weights used for the filter as I don't have the code available right now.

Thanks,



Edited By Peter on 1063737671