Cross Match Technologies Gmbh

Smiths Heimann Biometrics Gmbh

Joerg Standau

Torsten Eichhorn

Dirk Morgeneier

Torsten Gerling

Andy Friedl

Andreas Meister

Ralph Leszmann

The invention is directed to a method and an arrangement for the optoelectronic recording of a moving object, particularly for recording a finger that is rolled on a support surface. It is the object of the invention to find a novel possibility for electronic recording of rolled fingerprints which enables high-resolution individual images with a high image rate for joining the individual images without gaps to form a total image by means of simple sensors. This object is met, according to the invention, in that a shape surrounding the object is determined from the position and size of the object in at least one of the individual images read out from the image recording unit, in that a rectangle which is enlarged by tolerance allowances and which is oriented parallel to the row direction and column direction of the sensor is determined from the surrounding shape, and in that the enlarged rectangle is used to predict and adjust the size and position of an active pixel area of the image recording unit for at least one image to be read out subsequently, so that the read out active pixel area of the image recording unit is always kept small due to its adaptation and a higher image rate is realized in the sensor readout or data transfer.

Method and arrangement for electronic recording of rolled fingerprints

A process is disclosed for the electronic recording of an image of the surface of an object, which image can be displayed as a function G(x, y), wherein x and y are the coordinates of a respective image point of the image and G designates its gray value, wherein the object is recorded sequentially over different times t , where t >t , from different perspectives as function G in order to form the total image G from the individual images G (x, y) such as when rolling a finger for recording a fingerprint, wherein portions are cut out of the individual images and joined together depending on the respective recorded view, wherein a curved intersection line is determined for defining the portions of every image aside from the first image G by comparison with the image content of the previously recorded or assembled image G , wherein the portion of the image G is defined by this curved intersection line and the corresponding portion of the image G is subsequently added to this intersection line to form the total image G (x, y), wherein this intersection line is determined by forming a similarity function G (x, y) between the images G and G , which similarity function G (x, y) is external with identical gray values at identical image point coordinates or also by including their surroundings, and the intersection line is formed by a curve y (x) which runs through at least one extreme with a very high similarity of the similarity function G (x, y).

Process and apparatus for the electronic recording of an image

Growing community of inventors

Jena, Germany

Joerg Standau