1. An image generating method comprising: generating a first image based on first event signals that are output from an event-based vision sensor during a first time period and stored in a buffer; generating a second image based on second event signals that are output from the event-based vision sensor during a second time period and stored in the buffer; and aligning the first image and the second image to generate a third image having a quality that is higher than qualities of the first image and the second image.