Compression of medical images through DPCM coding of multi resolution and multidirectional subbands

This paper proposes a compression scheme for medical images through differential pulse code modulation coding of multi resolution and multidirectional subbands. Multi resolution representation of the medical images are obtained through laplacian pyramid which successfully decorrelates the image and thus reduces the redundant information by representing the image by a coarse signal at a lower resolution with several detail signals at successively higher resolutions. This multi scale transform is followed by directional transform to gather the nearby basis functions at the same scale in to linear structures. Thus each image is decomposed in to low pass subband and several band pass directional subbands that are encoded through DPCM. The proposed scheme was tested on various medical images and numerical results in this work shows the potential of various directional filter banks in the compression of medical images.