A medical imaging apparatus for processing a frame of a digital video signal, the apparatus includes an image sensor assembly, a frame replication device, a frame modification controller, and a video encoder. The image sensor assembly generates a first video signal having a first frame rate. The frame replication device replicates pixels of a respective frame of the first video signal to produce at least one replicated frame. The frame modification controller randomly modifies at least some of the respective pixels in the at least one replicated frame resulting in at least one modified replicated frame. The video encoder outputs a second video signal based on the at least one modified replicated frame.