Hewlett-packard Development Company, L.P.

Justsystem Corporation

Intel Corporation

Rahul Sukthankar

Matthew Mullin

Robert Stockton

Robert Alan Ulichney

Keiko Hasegawa

Tat-Jen Cham

James Mathew Rehg

J M Van Thong

Richard Caruana

Jm Van Thong

Trista P Chen

Thiruvadaimaruthur M Murali

Gita R Sukthankar

The embodiments of the invention relate to method for image-based retrieval of an image or text, comprising capturing a digital image; matching the digital image against digitally-stored documents; and retrieving one or more of the digitally-stored documents that match the digital image. Other embodiments relate to a device for image-based retrieval and rendering, comprising an image capturing device for capturing digital image; a device for processing the digital image to match it against digitally-stored documents; a device for retrieving a digitally-stored document that matches the digital image; and a device for rendering the selected retrieved image.

Image-based retrieval for high quality visual or acoustic rendering

Massive amounts of multimedia data are stored in databases supporting web pages and servers, including text, graphics, video and audio. Searching and finding matching multimedia images can be time and computationally intensive. A method for storing and retrieving image data includes computing a descriptor, such an a Fourier-Mellin Transform (FMT), corresponding to a multidimensional space indicative of each of the stored images and organizing each of the descriptors according to a set similarity metric. The set similarity metric is based on Locality-Sensitive Hashing (LSH), and orders descriptors near to other descriptors in the database. The set similarity metric employs set theory which allows distance between descriptors to be computed consistent with LSH. A target image for which a match is sought is then received, and a descriptor indicative of the target image is computed. The database is referenced, or mapped, to determine close matches in the database. Mapping includes selecting a candidate match descriptor from among the descriptors in the database and employing a distance metric derived from the similarity metric to determine if the candidate match descriptor is a match to the target descriptor.

System and method for efficiently finding near-similar images in massive databases

A system and method corrects luminance non-uniformity caused by images being obliquely projected onto a screen. A camera is used to record the geometry of the obliquely displayed image. Utilizing this recorded geometry, a homography is then derived that maps pixels between the projector's coordinate system and the screen's coordinate system. Utilizing the homography, the projector pixel that attends to the largest projected area on the screen is identified. Next, the ratio of each pixel's projected area to the largest projected area is computed. These ratios are then organized into an attenuation array that is used to produce 'corrected' luminance information from input image data. The projector is then driven with the 'corrected' luminance information.

System and method for correcting luminance non-uniformity of obliquely projected images

Media slides are often employed in conference sessions, meetings, lectures, and other interactive forums. The proliferation of laptops and handheld computers allows a speaker to present directly from the laptop by connecting to the projector at the conference site. Physically connecting and disconnecting each presenter's laptop to the projection apparatus, however, can be a clumsy and disruptive process, particularly since the presenters may be seated at various locations around the room. A wireless interface between a presentation server and a laptop in a multi-user multi-projector presentation system allows a media sequence from each media source to be displayed on a common display via the presentation server and the wireless interface. Presenters need not run or swap cables or other physical connections to switch media sources to the common display. The interface requires no software modification to the media source laptops and maintains independence between media sources and the server for security. The presentation server communicates with the media sources over the mouse port allowing innovative user interfaces, such as gesture recognition, to be employed for presentation control without additional software. Multiple projectors redundantly illuminate the display surface, dynamically eliminating shadows and other display artifacts when presenters walk between a projector and the screen. Distracting projected light cast on to the occluding presenters is automatically suppressed.

Wireless multi-user multi-projector presentation system

The present invention provides automatic correction of any distortions produced when computer projection displays are misaligned with respect to the projection surface (such as keystoning). Although sophisticated LCD projectors now offer partial solutions to this problem, they require specialized hardware and time-consuming manual adjustment. The two key concepts in the present invention are: (1) using an uncalibrated camera to observe the projected image; and (2) the image to be displayed is pre-warped so that the distortions induced by the misaligned projection system will exactly undo the distortion. The result is that an arbitrarily mounted projector (in an unknown orientation) still displays a perfectly aligned and rectilinear image.

Method and apparatus for automatic keystone correction

Disclosed is a computer-assisted method for analyzing the surroundings of a display device. At least two different patterns are displayed successively on a display device connected to a computer. A camera is also connected to the computer and is directed towards objects in front of the display device. Each time a pattern is displayed on the display device, at least one image of the surroundings is captured. The captured images are combined to create a difference image. The difference image is analyzed to interpret the objects in the surroundings. For example, calculations may be performed to segment the foreground from the background of the surroundings or to estimate the range (distance) of the objects from the display device. An apparatus for performing this computer-assisted method is also disclosed.

Method and apparatus for using illumination from a display for computer vision based user interfaces and biometric authentication

The present invention enables a user to automatically calibrate a projector-camera system to recover the mapping from a given point in the source (pre-projection) image and its corresponding point in the camera image, and vice versa. One or more calibration patterns are projected onto a flat surface with possibly unknown location and orientation by a projector with possibly unknown location, orientation and focal length. Images of these patterns are captured by a camera mounted at a possibly unknown location, orientation and with possibly unknown focal length. Parameters for mapping between the source image and the camera image are computed. The present invention can become an essential component of a projector-camera system, such as automatic keystone correction and vision-based control of computer systems.

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Somerville, MA, United States of America

Rahul Sukthankar