disc-probe

English | Simplified Chinese

Let an ordinary optical drive measure a disc’s spiral geometry by itself, then burn images onto the data side of a DVD-R or CD-R. The whole process requires no photographing or manual point-marking.

Along the River During the Qingming Festival, burned onto a Ritek F1 DVD-R. This is the direct output: all geometry comes from read timing. The disc was burned only once, with no test burns, photo calibration, or scan correction. The photo was taken with a phone, cropped to the disc surface, downscaled, and the background blurred.

Principle

Burning an image onto the data side requires knowing which angle on the disc sector N lands at. Each batch of discs has slight differences in track pitch and bit length. Over tens of thousands of turns these accumulate and the image twists into a swirl. The common remedy is to burn a calibration pattern, mark points from a photo, and correct repeatedly.

disc-probe lets the drive do the measuring. When the disc spins at constant speed, the moment a sector finishes reading is the moment it rotates under the read head. By reading two…