Method for reducing amount of stored digital image data without degrading a reconstituted image

A digital image data compression method, comprising:

• digitizing an uncompressed image area data field including digitizing said image area data field in the form of 512.times.512 pixels, wherein each pixel carries a numerical weight of zero through fifteen so as to have sixteen levels and can be represented by four binary bits;
• sectioning the digitized, uncompressed image area data field into a plurality of data blocks including sectioning the digitized image area data field into sixty-four 64.times.64.times.4 bit blocks, wherein each block is spatially oriented for retaining the integrity of an original image, and sub-sectioning each of the sixty-four blocks by one of a plurality of schemes, wherein each of the sixty-four blocks is divided into integral sub-blocks, with each of the sub-blocks retaining its spatial orientation;
• compressing the plurality of data blocks for representing each block in terms of its predominant data values and non-redundant occurrences including selecting predominant data values from each block, and encoding the selected predominant data values and the data values that are identical to a selected predominant data value including assigning a data bit code to each of the selected predominant data values and assigning to data values that are identical to a predominant value a data bit code corresponding to that of the predominant value;
• and
• storing remaining uncoded data values and the coded data values in a variable length record so that each data location within the record corresponds to the location of the data in the uncompressed image area data field.