ON-SITE LOCATION USING FAST IMAGE MATCHING Russian patent published in 2009 - IPC G06K9/50 G06K9/22 G06T7/60 

FIELD: physics.

SUBSTANCE: invention relates to location of part of a document captured in an image. A method is proposed for determining part of a document, which corresponds to the captured image, when the user makes a flourish in the document. Location of some of the images will be determined, for example by analysing pattern on the capture image, or from results of pixel-by-pixel comparison of the image with the document. Location of other images will be determined through segmentation of the sequence of images in a group of corresponding forms of the flourish. Information relating to localised images in the segment can then be used for determining position of non-localised images in the segment. The search area of a non-localised image in the document is established based on the position of the previous localised image and maximum speed or maximum acceleration of the pen. Turning and scale of the non-localised image are evaluated, as well as turning and scale of the localised image, and the non-localised image is deformed using this turning and scale. Pixel-by-pixel comparison between the deformed non-localised image and the search area in the document is done. If deformation of the non-localised image is successfully matched, parametres of image transformation are further specified.

EFFECT: increased efficiency of locating part of a document.

10 cl, 25 dwg