LTI FIR filters are used to process images, thus demonstrating that low-pass filtering is blurring, while high-pass filtering will sharpen edges.

DLTIDemo is a program that illustrates the relationship between the input and output of a discrete-time linear time-invariant (LTI) filter when the input is a sinusoidal function. The user is allowed to control the parameters of both the input sinusoid and the digital filter.

A brief introduction to FIR filters and how they can change the sound of speech signals.