Allan variance
The Allan variance (AVAR), also known as two-sample variance, is a measure of frequency stability in clocks, oscillators and amplifiers. It is named after David W. Allan and expressed mathematically a
Time deviation
Time deviation (TDEV), also known as , is the time stability of phase x versus observation interval τ of the measured clock source. The time deviation thus forms a standard deviation type of measureme
Sum of absolute differences
In digital image processing, the sum of absolute differences (SAD) is a measure of the similarity between image blocks. It is calculated by taking the absolute difference between each pixel in the ori
Modified Allan variance
The modified Allan variance (MVAR), also known as mod σy2(τ), is a variable bandwidth modified variant of Allan variance, a measurement of frequency stability in clocks, oscillators and amplifiers. It
Sum of absolute transformed differences
The sum of absolute transformed differences (SATD) is a block matching criterion widely used in fractional motion estimation for video compression. It works by taking a frequency transform, usually a