Convolution kernel
= Convolution kernel
{title2=$T_hf=f*h$}
A convolution kernel is the fixed <function> $h$ in an operator $T_hf=f*h$. It specifies how shifted input values are weighted. The averaging kernel $k_\varepsilon$ above has nonnegative values and <integral> one; arbitrary <convolution kernels> need not have either property. A <linear time-invariant system> uses its <impulse response> as a kernel when its output admits this representation.