Abstract: The present invention comprises a digital image processing method for detecting human eyes in a digital image. This method comprises the steps of: detecting iris pixels in the image; clustering the iris pixels, and selecting at least one of the following methods to identify eye positions: applying geometric reasoning to detect eye positions using the iris pixel clusters; applying a summation of squared difference method using the iris pixel clusters to detect eye positions; and applying a summation of squared difference method to detect eye positions from the pixels in the image. The method applied is selected on the basis of the number of iris pixel clusters. In another embodiment, the present invention also comprises a computer program product.

Abstract: A digital image processing method is taught for detecting human irises in a digital image. The method comprises the steps measuring the red intensity of the pixels in the image, determining the probability that each pixel is an iris based upon the red intensity of the pixel, determining the probability that each pixel is not an iris based upon the red intensity of the pixel; and determining whether the pixel is an iris by analyzing the relationship between the probability that the pixel is an iris and the probability that the pixel is not an iris. In one embodiment of the present invention, the determination as to whether a pixel is an iris pixel is then made based upon the application of a Bayes model to the probability that the pixel is not an iris, the probability of the occurrence of an iris in the identified region and probability of the occurrence of a non-iris pixel in the identified region.

Abstract: An alignment method is provided for a color scannerless range imaging system whereby the separate optical paths of colored texture and monochromatic range images may be precisely aligned. The range imaging system includes an illumination system for illuminating a scene with modulated infrared illumination, image forming optics for forming an image of the scene, optical means for forming first and second optical paths between the image forming optics and an image sensor, a transponder subject to modulation located in the first optical path for amplifying and converting infrared light to visible light to form a range image on the image sensor.

Abstract: A color scannerless range imaging system includes an illumination system for controllably illuminating a scene with modulated illumination and an image responsive element for capturing image light from the scene, including the modulated image light. The system establishes a primary optical path for directly image light toward the image responsive element. A beamsplitter located in the primary optical path separates the image light into two channels, a first channel including an infrared component and a second channel including a color texture component, whereby one of the channels traverses a secondary optical path distinct from the primary path. A modulating element is operative in the first channel to receive the infrared component and a modulating signal, and to generate a processed infrared component with phase data indicative of range information.

Abstract: A highly secure personal identification related document is achieved by having an area which contains machine readable information and also having a printed region having embedded data in the image printed thereon. The machine readable information as recorded has been encoded using a secure hash algorithm. For legitimate personal identification related documents, the machine readable data and the embedded data are identical information. The personal identification related document is used in conjunction with a reader system which includes a reader for the machine readable data, an optical scanner for scanning the image and data embedded therein, and a processor. The machine readable data is delivered to the processor which applies the secure hash algorithm thereto to generate a first data set. The digitized image data retrieved with the optical scanner is also delivered to the processor and the embedded data is retrieved therefrom to generate a second data set.

Abstract: A method of unambiguous range estimation is provided for use with a range imaging system that derives phase images from image pixels of a digital image. The method involves generating (a) a first phase image having one or more ambiguous phase intervals and (b) at least one additional phase image that is generated by shifting the phase intervals of the first phase image. Then at least one region of intersection between phase intervals in the two phase images is identified. Finally, the phase of at least one of the ambiguous phase intervals in the first phase image is adjusted based on values of the phase of the image pixels that belong to the region of intersection. As a result, the phase adjustment unwraps the phase ambiguity in the phase intervals of the first phase image.

Abstract: A panoramic image capture aid is formed in a photographic camera to assist a photographer in recording a series of film images that can be combined to form a panoramic image. The capture aid includes a viewing window on the camera, a first stripe indicator coupled to a film advance mechanism for moving with each film advance, and a second stripe indicator coupled to a compass for indicating the direction the camera is pointing. The first and second stripe indicators are supported on transparent rings concentrically arranged relative to the camera body such that their stripes intersect in the viewing window when the camera is properly positioned for the next image in the series of images.

Abstract: A method for image capture and estimation of range information is provided which uses photographic film as the image capture mechanism. A plurality of identical images are captured on film yielding an image bundle wherein each image in the image bundle is captured with a different phase offset. Fiducial marks are placed on the photographic film between adjacent images in the image bundle. The image bundle is developed and the developed images are scanned. The images of the image bundle are then registered by aligning the fiducial marks. The distance from the image capture device to object(s) in the images of the image bundle can then be estimated using the different phase offsets for each image. The range at a pixel location is estimated by selecting the intensity of the pixel at that location of each image and performing a best fit of a sine wave of one period through the points.

Abstract: A technique of capturing a stereoscopic panoramic photographic image of a scene, includes capturing a first 360.degree. panoramic image of a scene from a first point on a vertical axis; and capturing a second 360.degree. panoramic image of the scene from a second point on the vertical axis, the second point being displaced from the first point by a stereoscopic baseline distance.

Abstract: A system and method for creating three-dimensional or depth image font text characters using graphic three-dimensional object creation techniques and graphics processors. The text characters can be represented as set descriptions of the characters. The text characters can also be represented as a three-dimensional geometric model including polygons constructed from vertices defined by three-dimensional coordinates. The representations are stored in a font storage and when a user specifies the text characters to be used in a depth image along with the font to be used for the text characters, the geometric representations of the characters are retrieved. If stored as a set, the set is converted into a geometric plot. Appropriate scaling and surface texturing operations are performed as designated by the user to create three-dimensional text character graphic objects.

Abstract: A method of encoding and decoding a transaction card with a block of image data digitally representing the features of a digital portrait of an authorized transaction card user is disclosed along with apparatus for performing the method. The encoding method partitions the digital portrait of the transaction card user into feature blocks. Each feature block is compared against a library of like feature blocks to determine the best match with a pair of library feature blocks. The library's feature blocks are derived from a plurality of portraits taken from the general population. Each library feature block is represented (addressed for access) by a code-vector in a codebook.

Abstract: A method and apparatus in which a geometric graphic image of an object to be rendered as a depth image is created. The viewpoint of the viewer of the depth image is determined by the user. Once the viewpoint is determined the number of views is automatically determined along with the spacing between or positions of the views. The system adjusts the aspect ratio of each view and rotates the object prior to rendering. The rendered views are then stored as electronic interleaved images which are used to produce a depth image, such as a lenticular print.

Abstract: Method and apparatus for generating a halftone image. An ensemble of correlated minimum visual modulation two-dimensional binary patterns are provided. Each pattern corresponds to one density level of a digital input signal. The set of patterns is generated simultaneously to minimize an ensemble cost function which is the variance of non-zero spatial frequencies weighted by a human visual system modulation transfer function. The patterns are then modularly addressed to select bits to form halftone pattern.

Abstract: The disclosed method for compressing an image to be stored on a transaction card at one of a plurality of quality levels performs the steps of: a. providing a number of compression codebooks each corresponding to a quality level of the to be compressed image data; b. determining the quality level of the compressed image to be stored on the transaction card; c. determining the compression codebook that best corresponds to the determined quality level of step b; and d. compressing the image with the determined compression codebook. A decompression system is disclosed for processing, the transaction cards having the compressed image data stored thereon at one of a plurality of quality levels by, determining the maximum quality level common to the transaction card and the decompression system; and decompressing the compressed image data at the above maximum quality level. At each quality level of compression/decompression that represented image is of equal size.

Abstract: Multiple validations of printed documents incorporating image information and authorizing data on a printed document assist in the printed document validation process. This technique requires the authorized document holder to have an image identification accompany the application or production of the document. Image information is converted to a storable image that is used in one of a plurality of validating schemes that assures that the presenter of the printed document is not a substitute. Such schemes included visual comparison of the printed document presenter and extracted image information and validation that the data has not been altered. Non-reversible encryption of the data, as it is read from the document at the document presentation site is used to formulate encoded authorization data that is then compared against like encoded authorized document holder data stored at a centrally located data base.

Abstract: A system and method that generates computer graphic images using anti-aliasing rendering to create sets of offset images each of a lower resolution than the resolution desired. The anti-aliasing rendering is performed using offset weights that effectively cause a graphic model to be rendered at different rendering points for each low resolution image which are offset between low resolution images. The lower resolution offset images are then interlaced or combined to produce the desired high resolution image.

Abstract: Method and apparatus for generating a halftone image for a multi-level output device employing a dither matrix generated by minimizing a visual cost function. The dither matrix is addressed by the least significant bits of a pixel address and the value supplied by the dither matrix is added to the pixel value. The resulting sum is quantized in a quantizer to produce the multi-level halftone value.

Abstract: A technique involving the standardization of the subject matter of an image and the compression of the image using features of the standardization can provide for a high compression ratio. This technique can be used to improve the quality of a restored image for a predetermined amount of storage space.

Abstract: Method and associated apparatus for positioning a thermal donor media, having a plurality of transfer panels, each having a transfer area that is greater than the total area of a number of receiving media, such that a single transfer panel can provide an area of donor exclusively to each of the number of receiving media. The dimensions of unused areas of the thermal donor media are matched with the dimensions of the next to-be-printed image to enable a transfer printing to take place at an area that has dimensions that are equal to or greater than that required for the printed image. When an available area is identified the thermal donor media is moved into alignment and the transfer takes place. In one embodiment of the invention the thermal donor media is in the form of a ribbon that is wound between driven spools to bring unused areas into vertical printing alignment with the receiving media and the receiving media is displaced transverse to the ribbon to provide a horizontal alignment.

Abstract: In a string of characters on a storage medium in which a normally reserved character can appear in an inappropriate position, the field of characters is examined for a character which is not used in the field. The inappropriate reserved character is replaced by the permissible character. A field in the character string is reserved to permit the permissible character to be translated into the reserved character after the decoding of the character string.