Compression algorithms for force volume data I: Coding of prediction errors

The author considers the problem of reversible (lossless) compression of force volume data which are the three-dimensional arrays with 16-bit integer elements. Such arrays are the result of atomic force microscopy scanning of microobjects in the force mapping mode. The author proposes reversible compression algorithms of force volume data based on the universal arithmetic coding of their prediction errors. The author uses two methods of universal coding. The first method based on the statistical model of the source with the calculable sequence of states implies the decomposition of an error prediction sequence into two subsequences which are coded independently. The second method implies a choice of the appropriate weight while constructing the code probabilities used in arithmetic coding. The author constructs bit rate estimations for the proposed algorithms for five test arrays. The results show that combination of the universal coding methods mentioned above makes significant reduction of the bit rate. The bit rates of the most efficient algorithm among proposed practically applicable algorithms for the test arrays are 3.9285, 3.5268, 3.5024, 4.2813, and 4.2246 bit/pixel.