Perceptual coding at the threshold level for the Digital Cinema System Specification

An approach to perceptual coding at the threshold level, for supporting the Digital Cinema System Specification (DCSS) standard, is presented. The proposed Perceptual DCSS Coder (PDC) follows the approach of the Visually Lossless Grey scale Image Coder (VLGIC) of adapting Human Visual System (HVS) modelling to the JPEG2000 coder, but extends it to multi-frame application for DCSS. This PDC first applies pixel-domain temporal filtering to video frames. This is followed by the encoding of each colour component of individual frame with the VLGIC. The VLGIC is a JPEG2000 compliant coder that utilises a HVS based vision model to identify and remove imperceptible information in images/frames prior to coding operations. Experimental results show that the PDC provides improvement, in bitrate, over JPEG2000 reversible (lossless) mode. Furthermore, subjective assessments with 16 observers reveal no perceptible differences between PDC coded frames and their respective originals.