Not a valid DFT component

[darkownt]

How do I avoid this error or how do I fix images so that I can use them as a DFT component?

Thanks!
DO

[Geoff]

Just a wild guess. Do the image dimensions need to be a power of 2?

[Carlos Milovic]

Are you extracting the DFT components, and using the "same" (original or modified) ones to calculate the iDFT? Juan is using some FITS keywords to identify the components, (coordinate system, component type, etc), so if you are using a clone, or a synthetic image, it won't work with the stantard process.

If you are using PCL or PSJR classes, you may use any image you want, as long as it is a complex one.

[darkownt]

Just doing some pixel math in the marnitude component.

so the keywords are the culprit.  I ended up directly replacing the original image (in pixel math) with the recalculated one in order to do the inverse tranform...(presumably the necessary keywords were retained)  hitting undo if I wanted to revert.

Is there an easy way to simply copy keywords??  I suppose there must be.. Thanks!!