1. A method for extracting data from a scanned image of an array composed of pixels having one or more associated intensity values, the method comprising: computing row and column vectors by horizontal and vertical projection of pixel intensity values; computing corner-feature-image positions from the horizontal and vertical pixel-value projections; constructing a feature coordinate system using the computed corner-feature-image positions to index feature images in the scanned image of the array; and using the coordinate system to index and extract data from feature images within the scanned image of the array.