No reference, fuzzy weighted unsharp masking based DCT interpolation for better 2-D up-sampling

Up-sampling plays a crucial role while increasing the resolution of an image or a video intra frame through interpolation. Since the up-sampling process is analogous to a low pass filtering operation, it produces undesirable blurring artifacts that deteriorate the signal quality in terms of loss of fine details and critical edge information. In order to resolve this problem, a no reference, fuzzy weighted unsharp masking based DCT interpolation technique is proposed here. The proposed method is an anticipatory, spatial domain, fuzzy logic based preprocessing approach which sharpens the sub-sampled or low resolution video intra frames depending on their region statistics in order to compensate the blurring caused by the subsequent DCT interpolation technique. According to this method, the regions with high variance are sharpened more than the regions with low variance based on the Fuzzy rule base. This consequently results in the restoration of fine details and edge information in the reconstructed up-sampled video intra frame with improved objective and subjective quality.