Image signal
= Image signal
{title2=$u:\Omega\to\mathbb R$}
A grey-value <image signal> is a scalar function on an <image signal> domain or an array of pixel values. Continuous <image processing> models use spaces such as $L^2$, <Sobolev spaces> or the <BV space>, while discrete models use finite-dimensional arrays. The chosen representation distinguishes smooth transitions, noise and <image edges>.