431 results about "Color calibration" patented technology

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.

A multi-vision system includes chromaticity sensors for performing colorimetry of a plurality of display units. From colorimetry results obtained from the chromaticity sensors, a color conversion coefficient calculation unit inside a color calibration unit calculates the color conversion coefficient that is characteristic of each display unit. Calculated color conversion coefficients are stored in a color processing unit. The color calibration for this multi-vision system displays representing colors without a color conversion, and from colorimetry results of the representing colors for all the display units, a target color is decided automatically. For all display units, the color conversion coefficients are automatically calculated so that the representing colors are able to be displayed as a target color.

Apparatus and methods are disclosed for the calibration of a tracked imaging probe for use in image-guided surgical systems. The invention uses actual image data collected from an easily constructed calibration jig to provide data for the calibration algorithm. The calibration algorithm analytically develops a geometric relationship between the probe and the image so objects appearing in the collected image can be accurately described with reference to the probe. The invention can be used with either two or three dimensional image data-sets. The invention also has the ability to automatically determine the image scale factor when two dimensional data-sets are used.

A method and system for color calibration or color output device spectrophotoically measures at test target including a preselected test color value. A multi-dimensional LUT of the device is generated representative of the color information including the at least one preselected color. Producing a second image width device including the at least one preselected color located at a plurality of spatial locations in the second image. A second sensor measures the second image and a plurality of spatial locations having the preselected color for generating reflectance information for the preselected color at the plurality of spatial locations. An error is determined between the measured color of the one preselected color and the reflectance information at the other pixel locations. A multi-dimensional LUT is adjusted to minimize spatial uniformity errors at the other pixel locations, thus calibrating device color output spatially.

A computerized method and system for detection and quantification of changes in color on skin or internal tissue or organs within the human body. Digital images of the skin or tissue containing an area of interest are analyzed using the software of the invention, based on at least one channel of the LAB color system. The invention calculates the intensity and distribution of color present within the predetermined area of interest, and results in display of at least one color information attribute. The invention allows color calibration of the image to be performed in relation to a reference label having predetermined colors which surrounds the area of interest, prior to the analysis. The invention allows a threshold analysis to be performed, which graphically depicts the size and location of areas exhibiting significant change in color, which is a determinant factor in medical diagnosis.

Methods and electronic devices for performing color-based reaction testing of biological materials. The method includes capturing and interpreting digital images of an unexposed and later exposed paddle at various delay times within an automatically calibrated environment. The test paddle includes a unique identification mechanism (UID), a Reference Color Bar (RCB) providing samples of standardized colors for image color calibration, compensation and corrections, and several test-specific sequences of Chemical Test Pads (CTP). The method further includes locating the paddle in the image, extracting the UID and validating the paddle, extracting the RCB and locating the plurality of CTP in each image. The method further reduces image noise in the CTP and calibrates the image automatically according to lighting measurements performed on the RCB. To determine test results, the method further determines several distances between the CTP and its possible trajectory in the color space described by the Manufacturer Interpretation Color Chart.

The method and system for printer color calibration use a combination of a full-width array (FWA) or similar page-scanning mechanism in conjunction with an spectrophotometer color measurement system in the output path of a color printer for measuring colors (e.g., on printed test sheets, banner/separation pages, etc.) with or without requiring any manual operations or operator involvement. The automatic color balance control system produces spatial tonal reproduction values for all four of the primary colors by printing patches, measuring colors using the sensor combination and automatically readjusting the spatial tone reproduction curves until a satisfactory level of printed color accuracy and uniformity are obtained. While producing color balanced TRCs, the system will automatically lock the printer output to some predetermined color patch targets. In one particular preferred embodiment, this output is locked to neutral gray when target colors are set to neutral gray inside the digital front end (DFE). After converging to the targets, the control system returns full TRCs for use inside the normal print path.

A system and method for performing color correction based on physical measurements (or estimations) of color component spectra (e.g. red, green, blue color component spectra). A color correction system may comprise a spectrum sensing device, a color calibration processor, and a calculation unit. The spectrum sensing device may be configured to measure color component power spectra for pixels generated by one or more display devices on a display surface. The color calibration processor may receive power spectra for a given pixel from the spectrum sensing device and compute a set of transformation parameters in response to the power spectra. The transformation parameters characterize a color correction transformation for the given pixel. The color calibration processor may compute such a transformation parameter set for selected pixels in the pixel array. The calculation unit may be configured to (a) compute initial color values for an arbitrary pixel in the pixel array, (b) compute modified color values in response to the initial color values and one or more of the transformation parameter sets corresponding to one or more of the selected pixels, and (d) transmit the modified color values to the display device.

The present invention addresses the quantification of a printed tone scale for each individual color in a printing system, developing a linear tone scale derived in an independent color space and referenced from the shade of the unprinted substrate. The present invention determines the threshold for excessive ink coverage of a printing system on a specified substrate. This determination is based on a subjective evaluation of acceptable thresholds for bleed, cockle, show through, and image density. The method works in conjunction with a predefined test pattern printed on the specified substrate at fixed printing parameters, such as speed, dryer temperature, and web tension. This invention also includes an ability to limit the ink of each independent color in the system as a fraction of the total upper ink limit. Furthermore, this invention allows calibration of the tone scale of each color in the system using the color of the paper as a reference point. In addition, this invention facilitates the generation of separate sets of tone scale transformations for both graphics and text for each color in the system.

Scanner with light source calibration mechanism. The scanner includes a light source that generates a white light utilized to scan an image. The light source calibration mechanism includes a calibration color sensor that generates a calibration color sensor output. The light source calibration mechanism receives a predetermined color profile that can be, for example, the amount of red, green light, and blue light expected from the light source utilized by the scanner for scanning. The color calibration mechanism calibrates the light source of the scanner based on the output of the calibration color sensor and the predetermined color profile.

There is disclosed a format used in a remote proofing system to ensure that a printer device to which a print job is sent, operates within pre-determined calibration criteria for printing an image. Each job file has a job ticket, which defines a plurality of data types, which are to be checked for a printer device which is assigned to perform the printing. The parameters include ink level, environmental conditions (temperature, humidity), and media type. A printer device operates an algorithm to implement checks on the various parameters to determine whether a re-calibration process is required prior to printing an image. By sending a job file having no image data, a calibration of a printer can be achieved remotely, without necessarily printing an image.

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).

There is described an image processing method in which a scene is repeatedly imaged to form a series of input images. For at least a subset of the input images, a colour calibration procedure is conducted which populates a foreground colour histogram with the frequency of occurrence of colour values in a stencil area of the input image, and populates a background colour histogram with the frequency of occurrence of colour values outside of the stencil portion of the input image. For at least a subset of the input images, a colour replacement procedure is conducted which updates the stencil area based on a determination, from the colour values of pixels within the input image, of likelihood values representing the likelihood of pixels belonging to an image area of interest, the likelihood value for each colour value being determined from a combination of the foreground and background colour histograms, replaces the original colour values of pixels within the updated stencil area of the input image with replacement colour values, and displays the image on which colour replacement processing has been conducted. In this way, a stencil area is determined based on foreground/background histogramming, and used both to define an area to which colour replacement processing is to be conducted, and also an area for use in further populating the colour histograms to calibrate the colour replacement processing.

A color bar code system includes a camera reader to read at least one color bar code having a subset of N bar code colors, a color association unit and an identifier. The color association unit associates each point in a color space with one of the bar code colors. The color association unit is calibratable to the range of colors that the camera reader is expected to produce given at least one environmental condition in which it operates. The identifier uses the color association unit to identify an item associated with the bar code from the output of the camera reader.

To calibrate a tracking system a computing device locates an object in one or more images taken by an optical sensor. The computing device determines environment colors included in the image, the environment colors being colors in the one or more images that are not emitted by the object. The computing device determines one or more trackable colors that, if assumed by the object, will enable the computing device to track the object.

A calibration method for calibrating a fixed format emissive display device having a plurality of pixels is described In the display each pixel comprises at least three sub-pixels for emitting light of different real primary colours. The method comprises determining, for each real primary colour separately, a virtual target primary colour which can be reached by at least 80% of the pixels of the display, determining a colour gamut defined by the determined virtual target primary colours, and adjusting the drive currents to the sub-pixels to achieve a colour inside the determined colour gamut. A display having an extended range of colours is described, i.e. a gamut of colours that is more than the gamut provided by an n virtual primary colour based electronic multicolour display, as measured on a chromaticity diagram, for example. A color and/or brightness uniform image can be produced with this fixed format emissive display device.

In one embodiment, an apparatus for automatic test diagnosis of a test paddle is disclosed. The apparatus comprises a personal computing device including: a camera to capture images over time of test pads of a test paddle, a processor coupled to the camera, and a display device coupled to the processor. The processor analyzes the color changes over time of each test pad to determine a color trajectory over time for each test pad. The processor compares the color evolution trajectory for each test pad with color calibration curves for each test pad to determine an analyte concentration of a test biological sample, such as urine. During the analysis by the processor, the display device displays a user interface with results of the analyte concentration in response to the analysis over time.