IMAGE FINDER METHOD AND APPARATUS FOR PIXOGRAPHY AND OTHER PHOTO-RELATED REPRODUCTION APPLICATIONS

An image finder method and apparatus are provided for identifying a source image data file in a database based upon a printed image actually generated from a source image data file in the database. Input image data that represent a printed input image are received from a scanner. Source image data are received from the database that is defined by a plurality of different source image data files stored on a CD-ROM or other storage medium. Correlation operations are carried out to identify any source image data files that are highly correlated with the input image data. The results of the correlation operations are used to identify the source image data file from which the input printed image was actually generated or, if this is not possible, to identify more than one source image data file that could be the source image data file from which the printed input image was actually generated. Both the input image data and source image data are severely subsampled to obtain no more than about 1000 (and most preferably no more than 200) data values from each set of data for use in the correlation operation to provide for extremely fast processing without loss of accuracy.