A system configured to preform pre-compression on video sequences within a transform space to improve the compressibility of the video sequence during standard video encoding. In some cases, the pre-compression is configured to prevent the introduction of perceivable distortion into the video sequence or to substantially minimize the introduction of perceivable distortion. In some examples, a transform-Domain video processor may pre-compress or pre-process the video sequence in one, two, or three dimensional blocks or sequences using models of human visual contrast sensitivity.