After you hit the Start Processing button, you can see the progress bar which indicates the % of processing that is done:
First, NAÏVE collects metadata about the files you have uploaded. It may take up to several minutes, depending on the size of your folder, the number of files in it, and the file structure (read how to speed up the processing for macOS or Windows).
AI finds defective clips based on the mathematical parameters like camera shake levels or light in the frame. It marks the clips and moves them to another track in the XML. Usually, the processing takes as long as your footage is on a weaker computer. However, it depends on your PC power and faster computers process the footage rapidly.
Sometimes you need to abort the processing. The footage won't be deleted however all the progress on processing will be lost. 😥