Ethereal, I know. Not only do they look absolutely gorgeous, they are also an useful feature extraction technique for identifying lines or curves in an image. It works like this: imagine all the pixels in an original image (a) are sorted by a sift (b) such that only pixels that lie on a certain line can pass through. These pixels are then collected in a designated spot on the transformed image(c). Repeat this for all the lines you can possibly draw in this 2D space – every direction and every position. What you get at the end is a Hough Transform (c).
|Fact: Hough Transform sorts image pixels into a gorgeous picture.|
In case you were wondering, here are the original images for the beauties above.