Patent application number | Description | Published |
20090316213 | System and method of improving image quality in digital image scanning and printing by reducing noise in output image data - A system and method of reducing noise in output image data is provided. Grayscale image data having a plurality of pixels is received and processed. During processing, pixels which may produce noise are identified, and a mask associated with the image data is generated. The mask provides information related to the pixels, such as opaque and transparent regions for overlaying the pixels. The image data and the mask are compressed and stored. The mask assists in preventing the identified pixels from being visible when the image data is output, thereby reducing the noise in the image. | 12-24-2009 |
20100046856 | METHOD FOR BINARY TO CONTONE CONVERSION WITH NON-SOLID EDGE DETECTION - A system and method convert a pixel of binary image data to a pixel of contone image data by determining if a predetermined pixel of binary image data is part of a solid edge or part of a fuzzy edge. A binary to contone conversion circuit converts the predetermined pixel of binary image data to a pixel of a first contone image data value, and a filter circuit converts the predetermined pixel of binary image data to a pixel of a second contone image data value. The filter circuit uses an adaptive filtering operation wherein the adaptive filtering operation utilizes one of a plurality of sets of weighting coefficients to change a characteristic of the filtering operation. The set of weighting coefficients used in the filtering operation are selected in response to a fuzzy edge detection. A selection between the first contone image data value and the second contone image data value is made based upon the determination as whether the predetermined pixel of binary image data is part of a solid edge. | 02-25-2010 |
20100150460 | OCR-GUIDED TEXT TOKENIZATION OF DIGITAL IMAGES - An image processing method in which OCR is used to guide the text tokenization. More particularly, OCR is first performed on each symbol in the scanned image. For example, a symbol may be a number, letter, or other character. During the tokenization process, the OCR results are used to select appropriate matching criteria for each symbol. The symbols that are recognized as different characters are not allowed to be clustered into the same group. The symbols with the same OCR results are clustered according to the recognition confidence levels. | 06-17-2010 |
20100177328 | METHOD FOR REDUCING REGISTRATION DEFECTS IN COLOR PRINTING - A method and system modify a rasterized digital image to reduce registration artifacts, the image having a black plane and a color plane by determining if a pixel is part of a connected black region and if the pixel is part of a connected color region. It is determined if the pixel is part of a connected black region and a connected color region that are contiguous. A dilation operation is performed on the color plane value of the pixel if the pixel is part of a connected black region and a connected color region that are contiguous. | 07-15-2010 |
20100177329 | METHOD FOR REDUCING REGISTRATION DEFECTS IN COLOR PRINTING - A method and system modify a rasterized digital image to reduce registration artifacts, the image having a black plane and a color plane by determining if a pixel is part of a connected black region and if the pixel is part of a connected color region. It is determined if the pixel is part of a connected black region and a connected color region that are contiguous. A dilation operation is performed on the color plane value of the pixel if the pixel is part of a connected black region and a connected color region that are contiguous. | 07-15-2010 |
20110310278 | SYSTEMS AND METHODS FOR ADAPTIVE CONTROL AND DYNAMIC RANGE EXTENSION OF IMAGE SENSORS - Systems and methods are provided for obtaining adaptive exposure control and dynamic range extension of image sensors. In some embodiments, an image sensor of an image system can include a pixel array with one or more clear pixels. The image system can separately control the amount of time that pixels in different lines of the pixel array are exposed to light. As a result, the image system can adjust the exposure times to prevent over-saturation of the clear pixels, while also allowing color pixels of the pixel array to be exposed to light for a longer period of time. In some embodiments, the dynamic range of the image system can be extended through a reconstruction and interpolation process. For example, a signal reconstruction module can extend the dynamic range of one or more green pixels by combining signals associated with green pixels in different lines of the pixel array. | 12-22-2011 |
20110317048 | IMAGE SENSOR WITH DUAL LAYER PHOTODIODE STRUCTURE - An image system with a dual layer photodiode structure is provided for processing color images. In particular, the image system can include an image sensor that can include photodiodes with a dual layer photodiode structure. In some embodiments, the dual layer photodiode can include a first layer of photodiodes (e.g., a bottom layer), an insulation layer disposed on the first layer of photodiodes, and a second layer of photodiodes (e.g., a top layer) disposed on the insulation layer. The first layer of photodiodes can include one or more suitable pixels (e.g., green, blue, clear, luminance, and/or infrared pixels). Likewise, the second layer of photodiodes can include one or more suitable pixels (e.g., green, red, clear, luminance, and/or infrared pixels). An image sensor incorporating dual layer photodiodes can gain light sensitivity with additional clear pixels and maintain luminance information with green pixels. | 12-29-2011 |
20120019669 | SYSTEMS AND METHODS FOR CALIBRATING IMAGE SENSORS - Systems and methods are provided for calibrating image sensors. In some embodiments, a processing module of an image system can automatically perform a self-calibration process after a production unit of an image sensor has been integrated into an end product system. For example, the processing module can calibrate a production unit based on one or more reference pixels of the production unit, where the one or more reference pixels have minimal color filtration. In some embodiments, the processing module may perform local calibrations by correcting specifically for spatial variations in a color filter array (“CFA”). In some embodiments, the processing module can perform global calibrations by correcting for optical density variations in the CFA. In some embodiments, a processing module can determine whether the cause of production variations is related to production variations of a CFA or production variations of an infrared (“IR”) cutoff filter. | 01-26-2012 |
20120025080 | COLOR CORRECTION CIRCUITRY AND METHODS FOR DUAL-BAND IMAGING SYSTEMS - An imaging system may include a dual-band image sensor that captures visible and near-infrared light and image processing circuitry that performs color corrections on images captured by the dual-band image sensor. The image processing circuitry may analyze each captured image in two different color spaces to determine what type of light source lit each image. The image processing circuitry may determine whether an image was lit by a light source having a relatively high proportion of near-infrared emissions such as an incandescent light, a light source having a relatively low proportion of near-infrared emissions such as a fluorescent light, or a light source having an intermediate proportion of near-infrared emissions such as sunlight or other blackbody radiator. After determining what type of light source lit an image, the image processing circuitry may adjust color balances in that image using a color correction matrix associated with that type of light source. | 02-02-2012 |
20130093914 | Transformations and White Point Constraint Solutions for a Novel Chromaticity Space - A novel chromaticity space is disclosed that may be used as a framework to implement an auto-white balance solution or other color image processing solutions that take advantage of the particular properties of the novel chromaticity space. The chromaticity space may be defined by using a series of mathematical transformations having parameters that are optimized to adapt to specific sensors' spectral sensitivities. The unique properties of the novel chromaticity space provide a conscious white point constraining strategy with clear physical meaning. In this chromaticity space, the ranges of possible white points under different kinds of lighting conditions can be defined by polygons. Because of the physical meaning the chromaticity space, the projection that is needed to bring an initially “out-of-bounds” white point back into the polygon also carries physical meaning, making the definition of projection behavior and its consequences conceptually clean and predictable. | 04-18-2013 |
20130093915 | Multi-Illuminant Color Matrix Representation and Interpolation Based on Estimated White Points - This disclosure pertains to devices, methods, and computer readable media for improved accuracy of color correction matrix (CCM) coefficient determination based on estimated white point, while maintaining a relatively smooth variation of CCM coefficients over the white point space. The techniques disclosed herein may be achieved via the storage of a limited number of determined CCM multiplier vectors and thus be effective in the camera image pipelines of real image capture devices. With the more accurate CCMs calculated with the disclosed techniques, visible improvement in rendered colors may be achieved as compared to using interpolation from a handful of corner CCMs. The color correction techniques described herein may be implemented by dedicated or general purpose hardware, general application software, or a combination of software and hardware in a computer system. | 04-18-2013 |
20130093916 | Use of Noise-Optimized Selection Criteria to Calculate Scene White Points - Methods, devices and computer readable media for implementing a “selective gray world” approach for color balancing are described. The disclosed techniques involve the use of noise-optimized selection criteria and, more specifically, in some embodiments, the interpolation between corresponding values in noise-optimized weighting tables when calculating white balance gains. Estimated scene lux levels may provide a valuable indicator of expected scene noise levels. The image processing techniques described herein may be executed by an image capture device or a general purpose processor (e.g., personal computer) executing a user-level software application. The described color balancing techniques may be implemented by dedicated or general purpose hardware, general application software, or a combination of software and hardware in a computer system. | 04-18-2013 |
20130093917 | Alleviating Dominant Color Failure in Automatic White Balance Using Histogram Trimming - Methods, devices and computer readable media for implementing novel dominant color alleviation techniques for color balancing are described. The techniques take advantage of unique properties of 2D image data histograms accumulated in a chromaticity space, along with other factors such as estimated scene lux and knowledge of plausible scene illuminant white point values within the chromaticity space. The accumulated 2D image data histograms may be refined and “trimmed,” such that the resultant image data passed to an auto white balance solution has much less influence from the dominant colors in the image, even those that overlap the plausible scene illuminant color region. The described techniques provide for white point estimates that are much less prone to dominant color failures. | 04-18-2013 |
20130308021 | SYSTEMS AND METHODS FOR ADAPTIVE CONTROL AND DYNAMIC RANGE EXTENSION OF IMAGE SENSORS - Systems and methods are provided for obtaining adaptive exposure control and dynamic range extension of image sensors. In some embodiments, an image sensor of an image system can include a pixel array with one or more clear pixels. The image system can separately control the amount of time that pixels in different lines of the pixel array are exposed to light. As a result, the image system can adjust the exposure times to prevent over-saturation of the clear pixels, while also allowing color pixels of the pixel array to be exposed to light for a longer period of time. In some embodiments, the dynamic range of the image system can be extended through a reconstruction and interpolation process. For example, a signal reconstruction module can extend the dynamic range of one or more green pixels by combining signals associated with green pixels in different lines of the pixel array. | 11-21-2013 |
20150070537 | Lens Shading Modulation - This disclosure pertains to systems, methods, and computer readable media for performing lens shading correction (LSC) operations that modulate gains based on scene lux level and lens focus distance. These gains compensate for both color lens shading (i.e., the deviation between R, G, and B channels) and vignetting (i.e., the drop off in pixel intensity around the edges of an image). As scene illuminance increases, the sensor captures more signal from the actual scene, and the lens shading effects begin to appear. To deal with the situation, the lens shading gains are configured to adaptively ‘scale down’ when scene lux approaches zero and ‘scale up’ when scene lux changes from near zero to become larger. The lens shading gain may also be modulated based on the focus distance. For optical systems without zoom, the inventors have discovered that the amount of lens shading fall off changes as focus distance changes. | 03-12-2015 |
20150070570 | Adaptive Auto Exposure and Dynamic Range Compensation - This disclosure pertains to systems, methods, and computer readable media for extending the dynamic range of images using an operation referred to herein as “Adaptive Auto Exposure” (AAE). According to the embodiments disclosed herein, the AAE-enabled higher dynamic range capture operations are accomplished without blending multiple or bracketed exposure captures (as is the case with traditional high dynamic range (HDR) photography). AAE also enables high signal-to-noise ratio (SNR) rendering when scene content allows for it and/or certain highlight clipping is tolerable. Decisions with regard to preferred AE strategies may be based, at least in part, on one or more of the following: sensor characteristics; scene content; and pre-defined preferences under different scenarios. | 03-12-2015 |