How to Do Live FFT of sub-area (ROI) of a Image using DigitalMicrograph script

Question

I mean both the sub-area change and the data change will trigger the FFT process, so I can see sub-area FFT of a Live Image.

Answer 1

You can simply use the command NewLiveFFT for this. Below is an example script. Note that if a ROI selection is present on the image, it will be used. Otherwise the whole image is used. You can, of course, create a specific ROI via script and add it as well.

number kRasterDisplay = 1
image img
if (!GetFrontImage(img)) exit(0)
imageDisplay disp = img.ImageGetImageDisplay(0)
if ( kRasterDisplay != disp.ImageDisplayGetDisplayType() ) exit(0)

ROI sel = disp.ImageDisplayGetRoi(0)

NewLiveFFT(disp,sel,0)

Note that LiveFFTs will automatically stop if the data type of the source image changes, or if the source image is closed. You can also not resize the ROI of a LiveFFT. It would be possible to create a script which allows ROI resize, but then you would have to use ROI-listeners and code all the according links and FFTs yourself.