Patent ID: 6459821
Filing Date: 2002-10-01
Classification: G06K,G06T,H04N

Abstract:
In a digital image alignment system, apparatus for aligning a first fragment of an image to a second fragment of an image comprising:means for identifying a plurality of interest points in an overlapping area within said first image fragment to match to a region of said second image fragment; means for obtaining a mean pixel value for regions of said first image surrounding each of said plurality of interest points, said regions having shapes chosen so that their mean pixel values are independent of rotational alignment to said first image fragment; means for including within a plurality of selected alignments for each interest point only alignments for which mean pixel values of regions of said second image fragment aligned with said interest point have substantially similar mean pixel values to said region surrounding said interest point; and means for, for each of said plurality of interest points, measuring an alignment error of said plurality of possible alignments of regions of said second image fragment to a region surrounding the interest point in accordance with a predetermined metric.