English: An illustration of ringing artifacts, showing a quarter-circle of light gray on dark gray with 3 levels of artifacts on each side (overshoot, ring 1, ring 2). Produced by taking the original image (a single sharp transition, without artifacts), then upscaling by 2× via a Lanczos-3 filter, sharpening via unsharp masking (radius 1, amount 10 (1000%), then upscaling again by 2× with Lanczos-2.