Question: What overarching terms could be used to refer to the use of a Fourier transform, Hankel transform, etc. as well as discrete versions of those, such as a Fast Fourier Transform (FFT), etc.?
Context: This is for language describing a step within a patent claim. This step in principle involves the use of any transform that could be used to represent a 2D image in terms of a different set of basis images (such as an FFT, where the basis set are 2D sinusoidal waves).
Because it's for a patent claim, it's not necessarily math jargon specifically I'm looking for (which might be a bad choice if it's not commonly understood in the community, or has a different common meaning), but something which could reasonably be interpreted in the science/signal engineering, etc. communities to refer to what I want it to.
My ideas: My initial thought was to say something like 'integral transform', but maybe that wouldn't really apply to the discrete versions - particularly something like the FFT since you could argue that no integration is really involved.
Another thought was something like 'mathematical transform', but I'm afraid that's too broad, because it could apply to simply squaring functions, etc.