CAT-5 Video Variable Filters
It is often beneficial to use a video driver at the output of a video encoder for power savings, line driving, and additional circuit protection. The video driver is typically configured as an active filter, also known as a reconstruction or anti-imaging filter. The purpose of the reconstruction filter is twofold: it blocks the higher frequency components (above the Nyquist frequency) that were introduced into the video signal as part of the digitization process and provides gain to drive the external 75 Ω cable to the video display.