1. In a method for computerized analysis of temporally sequential digital chest images, each including data corresponding to a pair of lungs, the improvement comprising the steps of: (a) determining first shift values between pixels of a first digital chest image and corresponding pixels of a second digital chest image, comprising, selecting plural template regions of interest (ROIs) in the first digital chest image and corresponding search area ROIs in the second digital chest image, determining shift values between pixels centered in each template ROI and pixels centered in a respective search area ROI and exhibiting highest cross-correlation with respect to said template ROI, determining shift vectors for each of said shift values, a first cumulative histogram of said shift vectors for pixels in one lung, and a second cumulative histogram of said shift vectors for pixels in the other lung, selecting, based on characteristics of said first and second cumulative histograms of shift vectors, plural of said shift values for derivation of fitted shift values, perfoming two-dimentional fitting on the shift values selected in the preceding step to derive said fitted shift values which serve as said first shift values; and (b) warping said second digital chest image using the first shift values to obtain a warped image in which spatial locations of pixels are varied in relation to said first shift values.