Random Pattern (Noise) Test Chart

The Imatest Random Pattern chart is a variant of the Dead Leaves chart designed to measure texture sharpness.The Random pattern is the extreme pattern for noise reduction: it maximizes noise reduction while minimizing sharpening, improving the accuracy and robustness of measurements. In addition, gray regions to the left and right of the chart facilitate noise removal (using a technique where gray patch noise Power Spectral Density is subtracted from the signal + noise PSD of the central Spilled coins region).