To provide an image processing system and the like which can correct image distortions and provide properly overlapped images when a plurality of projectors are used to project overlapped images, a projector includes: an image projection section projecting an image based on image signals to display the image in a manner to overlap another image projected from another projector at a projection target area; sensing section sensing an image and generating sensing information; overlap-area detecting section detecting projection areas for the projection target area, and detecting an overlap area at which the projection areas overlap, based on the sensing information; correction information generating section generating correction information indicating information for positions of the projection areas and a position of the overlap area; and projection area correction section correcting image signals, based on the correction information, to project an image onto a region corresponding to the overlap area.

Image processing system, projector, program, information storage medium and image processing method

The system provides for controlling color reproduction of input color image data representing one or more pages or page constituents in a network having nodes (or sites). Each one of the nodes comprises at least one rendering device. The system distributes the input color image data from one of the nodes to other nodes, and provides a data structure (virtual proof) in the network. This data structure has components shared by the nodes and other components present only at each node. Next, the system has means for providing color calibration data at each node characterizing output colors (colorants) of the rendering device of the node, and means for producing at each node, responsive to the color calibration data of the rendering device of the node, information for transforming the input color image data into output color image data at the rendering device of the node. The information is then stored in the data structure in different ones of the shared and other components. Means are provided in the system for transforming at each node the input color image data into output color image data for the rendering device of the node responsive to the information in the data structure. The rendering device of each node renders a color reproduction of the page constituents responsive to the output color image data, wherein colors displayed in the reproduction at the rendering device of each node appear substantially the same within the output colors attainable by the rendering devices. The system further has means for verifying at each node that the information for the rendering device of the node properly transformed the input color image data into the output color image data, and means for revising the information stored in the data structure at the node responsive to results of the verifying means. Shared components of the data structure may also store color preferences selected by a user. The information producing means of the system may further operate responsive to both the color calibration data and the color preferences. The rendering devices in the system can provide color reproductions having three or four colorants, and may provide more than four output colors (color inks).

System for distributing and controlling color reproduction at multiple sites

A display system that can be calibrated and re-calibrated with a minimal amount of manual intervention. To accomplish this, one or more cameras are provided to capture an image of the display screen. The resulting captured image is processed to identify any non-desirable characteristics, including visible artifacts such as seams, bands, rings, etc. Once the non-desirable characteristics are identified, an appropriate transformation function is determined. The transformation function is used to pre-warp the input video signal that is provided to the display such that the non-desirable characteristics are reduced or eliminated from the display. The transformation function preferably compensates for spatial non-uniformity, color non-uniformity, luminance non-uniformity, and other visible artifacts.

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Method and apparatus for calibrating a tiled display

A super-resolution display derives a map by selectively driving the display while sensing the display output. A stored pixel correction function based on the mapping is applied to pixel data corresponding to the images to be displayed, and the display is driven from the corrected or modified pixel data. This can be used to correct for many types of distortion and to blend images from plural projectors. Pixel data is stored in a frame buffer, and the pixel correction function is applied to the pixel data between the frame buffer and the display, or alternatively, the pixel correction function is applied first, and corrected pixel data is stored in the frame buffer. The display is then driven from the corrected pixel data. In a preferred embodiment, the display comprises a plurality of projectors. The pixel correction function corrects for misalignment of projected overlapping pixel arrays, and blends the overlapping projection regions. In another embodiment, the projected images from plural projectors completely overlap, and the projectors have a small fill factor, resulting in a super-high resolution display. A single projector embodiment corrects for imperfections across the display. The correction functions are derived by composing a screen to sensor mapping with projector to sensor mappings. These mappings are established by optically sensing physical or projected test charts. Preferably, the optical sensor comprises at least one camera, such as a CCD camera. Alternatively, the optical sensor may comprise a pair of orthogonal linear sensor arrays.

Super-resolution display

Color calibration of color image rendering devices, such as large color displays, which operate by either projection or emission of images, utilize internal color measurement instrument or external color measurement modules locatable on a wall or speaker. A dual use camera is provided for a portable or laptop computer, or a cellular phone, handset, personal digital assistant or other handheld device with a digital camera, in which one of the camera or a display is movable with respect to the other to enable the camera in a first mode to capture images of the display for enabling calibration of the display, and in a second mode for capturing image other than of the display. The displays may represent rendering devices for enabling virtual proofing in a network, or may be part of stand-alone systems and apparatuses for color calibration. Improved calibration is also provided for sensing and correcting for non-uniformities of rendering devices, such as color displays, printer, presses, or other color image rendering device.

Color calibration of color image rendering devices

A projection display device is provided with a negative feedback chain designed to correct all the faults of the projected image, said faults resulting as much from the projection tubes and from their optic systems (geometrical or focusing faults) as from the differences between these tubes (faults in convergence, colorimetry or uniformity of brilliance). The negative feedback chain comprises a test chart generating means, a means to retake the entire projected image and means for the comparision of the signals coming from the test image and from the retaken image. Correction signals are prepared on the basis of this comparison and are applied to the different control circuits defining the projection characteristics. The disclosed device can also be used for the real-time follow-up of the adjustments obtained in a phase prior to the projection of the sequence of useful video images. The invention can be applied notably to video projectors, retro-projection display devices or beam-index tubes.

Projection display device with negative feedback loop to correct all the faults of the projected image

An automatic defect correction drive utilizing feedback in an image display device. According to the present invention, during an acquisition phase, a test image constituted of bright points of known positions distributed on a screen is displayed. This displayed image is then analyzed via an image acquisition device, to deduce from it the scanning, focusing and amplitude corrections to be applied to the display, so that the test pixels displayed on the screen have their expected positions and characteristics. These corrections are then interpolated for the intermediate pixels between test points, and then, during a continuation phase, these corrections are updated.

Process and device for image display with automatic defect correction by feedback

A data transmission and/or acquisition device and method are disclosed. The said device and method use two cross polarizations of an electromagnetic wave and a magnetic recording device. The invention pertains to phase/amplitude modulation using two phase-modulated signals transmitted on two orthogonal polarizations. At reception, the vector sum of the two signals is added taken. The resultant signal is amplitude-modulated and/or phase-modulated. The invention can be applied especially to television and radio transmitters, radars and telecommunications equipment.

Device and method for data transmission and/or acquisition using two cross polarizations of an electromagnetic wave and magnetic recording device

The present invention relates to a process for transmitting a digitized signal according to OFDM (Orthogonal Frequency Division Multiplexing) type multicarrier modulation using N orthogonal channels. In accordance with the present invention, the channels are divided into two, N/2 channels. corresponding to a first frequency band being sent via a first transmission track ( 3 A, 4 A, 5 A, 6 A, 7 A) according to a first polarization and the remaining N/2 channels being brought back into the same frequency band and sent via a second transmission track ( 3 B, 4 B, 5 B, 6 B, 7 B) according to a second polarization crossed with respect to the first.

Process for transmitting a digitized signal according to OFDM type multicarrier modulation, transmitter and receiver for the implementation of the said process

The invention relates to a projection-type display apparatus provided with a feedback chain intended to correct all the defects exhibited by the projected image, these defects resulting both from the projection tubes and from their optics (geometric or focusing defects) and from differences between these tubes (defects of convergence, colorimetry, uniformity of brightness). The feedback chain includes a generator means (6) for a test-card image, a means (3) of recapturing the entire projected image, and means (4) of comparing the signals output by the test image and by the recaptured image; correction signals are formulated from this comparison and are applied to the various control circuits (5) defining the projection characteristics. … The device according to the invention is used also in the real-time tracking of adjustments obtained in a phase prior to the projecting of the sequence of useful video images. … The invention applies in particular to video projectors, to overhead projector display devices or to beam-index tubes. … …

Yvon Fouche

Papers

Projection display device with negative feedback loop to correct all the faults of the projected image

Process and device for image display with automatic defect correction by feedback

Device and method for data transmission and/or acquisition using two cross polarizations of an electromagnetic wave and magnetic recording device

Process for transmitting a digitized signal according to OFDM type multicarrier modulation, transmitter and receiver for the implementation of the said process

Projection-type display apparatus with feedback loop for correcting all the defects of the projected image