System and method for determining the quality of fingerprint images

A method of determining a quality measure of a fingerprint image, comprising the steps of:

• selecting at least one block of pixels in the fingerprint image;
• determining whether the selected at least one block has a prominent direction, wherein those blocks having a prominent direction are defined as being directional blocks and wherein those blocks not having a prominent direction are defined as being non-directional blocks;
• determining that a particular block is a foreground block if the number of pixels within the block, whose absolute value of an intensity difference between the pixel and at least one neighboring pixel is greater than a a background threshold, and determining that a particular block is a background block if the number of pixels within the block, whose absolute value of the intensity difference between the pixel and the at least one neighboring pixel is less than the background threshold;
• creating regions of contiguous foreground and directional blocks;
• and
• determining the quality measure as a ratio of the areas of all of the created regions to an area of the foreground.

A method for processing an image of a fingerprint, comprising steps of:

• obtaining an image of a fingerprint, the image being comprised of pixels;
• processing the fingerprint image to partition the image into blocks of pixels each specified to be one of a background block or a foreground block;
• further processing foreground blocks to obtain regions each comprised of set of contiguous foreground blocks wherein the pixels of a block exhibit a prominent directionality;
• weighting blocks as a function of distance from a common reference point within the fingerprint image;
• determining a quality measure for the fingerprint image by computing a ratio of a summation of total weights of blocks exhibiting a prominent directionality to a summation of the weights of the foreground blocks;
• and
• directing further processing of the fingerprint image based on the determined quality measure by comparing the determined quality measure to a quality threshold.