Displays the autocorrelation function of images and line profiles. For images, this is equivalent to the macro command of the same name supplied with NIH Image. If a line selection has been made on an image, or if the current window is a profile plot or an FFT of a profile, then the autocorrelation of the profile will be calculated and displayed.

An autocorrelation of a line profile can be treated in the same way as a profile plot or an FFT of a profile:

• If the line selection is nudged using the cursor keys or moved using the mouse, then the autocorrelation window will update in real time.
• Autocorrelation windows can be copied using Duplicate and saved as PICT or TIFF images.
• Autocorrelation data can be saved to a text file using Export.