Abstract: The invention provides a new method and apparatus for NTSC and PAL image sensors which employs fusion of adjacent row pixel charge samples to generate image data for a row. A variety of fusion schemes are possible for fusing the pixel signals from the adjacent rows. The rows of pixels are scanned so that each scan takes an odd row signal sample and, in some cases, an adjacent even row signal sample when specified conditions are met. One sampled row of the two adjacent rows integrate an image with a first integration period while the other adjacent row integrates an image with a second integration period.

Abstract: The invention provides a new method and apparatus for NTSC and PAL image sensors which employs fusion of adjacent row pixel charge samples to generate image data for a row. A variety of fusion schemes are possible for fusing the pixel signals from the adjacent rows. The rows of pixels are scanned so that each scan takes an odd row signal sample and, in some cases, an adjacent even row signal sample when specified conditions are met. One sampled row of the two adjacent rows integrate an image with a first integration period while the other adjacent row integrates an image with a second integration period.

Abstract: A method, apparatus, and system that use a white balance operation. A selecting process is applied to each pixel selected and considered for automatic white balance statistics to determine the distance from the selected pixel to a white curve defined in a white area corresponding to an image sensor.

Abstract: A method, apparatus and system that allows for the identification of defective pixels, for example, defective pixel clusters, in an imager device. The method, apparatus and system determine, during use of the imager device, that a pixel defect, e.g., cluster defect, exists and accurately maps the location of the defective pixel. By analyzing more than one frame of an image, the method increases the accuracy of the defect mapping, which is used to improve the quality of the resulting image data.

Abstract: Methods and apparatuses of reducing noise in an image by obtaining a first value for a target pixel, obtaining a respective second value for neighboring pixels surrounding the target pixel, for each neighboring pixel, comparing a difference between the first value and the second value to a threshold value and selectively replacing the first value with an average value obtained from the first value and at least a subset of the second values from the neighboring pixels which have an associated difference which is less than the threshold value based on a result of the comparing step. In a further modification, less than all neighboring pixels which have an associated difference which is less than the threshold value are used in the averaging.

Abstract: A method of determining pixel hue values from red, green, and blue color component inputs. The hue color circle is divided into a number of segments. Each segment is assigned an output hue value. A set of conditionals are provided to describe each segment, define the outputs and create a data set that may be loaded into a system to provide hue determination without complex division or multiplication operations.

Abstract: Image sensor with a successive approximation A/D converter that automatically compensates for black level and provides a signal indicative of the difference between the reset level and the signal level. Black level for each of a plurality of color pixels may be obtained. This may be obtained from, for example, an image sensor with intentionally darkened pixels. Levels from these pixels are sampled, and an average of these pixels is used to form a black level for similarly-colored pixels. That black level is stored, and used to drive a D/A converter. Another D/A converter forms the actual conversion, and is compared to a reference. The reference is selected such that the output signal is automatically compensated for black level, and also corresponds to the difference between signal and reset.

Abstract: A method and apparatus for accurately auto focusing a lens of an imaging device. An imaged scene is split into an array of zones. The minimum and maximum sharpness score for each zone is determined over a plurality of lens positions. A histogram of the lens positions of the corresponding maximum weighted sharpness score for each zone is created. The peak of the histogram is determined to be the best focus position for a given scene.

Abstract: In an image processing system, the imager gain and the exposure time are adjusted based on a predefined stepping sequence using a stepping table designed to maximize the signal-to-noise ratio in the image. This is achieved by providing a stepping sequence with each step having the largest suitable integration time (exposure) and an appropriate amplifier and digital gain setting, while achieving an equal relative percentage change in image brightness between adjacent sequence steps. The size of the executed AE steps is proportional to the distance between a current image luminance and the target luminance. This is achieved by the capability to skip one or more steps in the stepping sequence, if appropriate, for each relevant executed step, with the number of skipped steps, if any, being proportional to the magnitude of the deviation from the target brightness.

Abstract: A method and apparatus for color plane interpolation are provided which interpolates the color values of pixels differently depending on an edge direction and whether a pixel is at an edge within an image. The use of the edge detection during the interpolation of each of the colors present in the color pattern helps reduce some of the disadvantages of the loss of image sharpness abundant in known demosaicing techniques.

Abstract: A method of reducing noise in an image including steps for obtaining a first value for a target pixel, obtaining a respective second value for each neighboring pixel surrounding the target pixel and having the same color as the target pixel, for each neighboring pixel, comparing a difference between said first value and said second value to a threshold value, and replacing the first value with an average value obtained from the first value and at all second values from the neighboring pixels which have an associated difference which is less than or equal to the threshold value based on a result of the comparing step.

Abstract: A CMOS imager in which a CMOS image sensor, a color image processing module and an image compression module are all provided on a single die. Both the color image processing module and the image compression module incorporate pipelined architectures to process the image data at a video rate in a massively parallel fashion.

Abstract: An image processing system and method compares each pixel of an image obtained from an image sensor array with at least eight surrounding pixels of the same color in the filter array. If the signal of a given pixel is larger than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the maximum signal value among the surrounding eight pixels of the same color. Similarly, if the signal of a given pixel is smaller than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the minimum signal value among the surrounding eight pixels of the same color.

Abstract: An image processing system and method compares each pixel of an image obtained from an image sensor array with at least eight surrounding pixels of the same color in the filter array. If the signal of a given pixel is larger than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the maximum signal value among the surrounding eight pixels of the same color. Similarly, if the signal of a given pixel is smaller than the respective signals of all eight surrounding pixels of the same color, then the value of that central pixel signal is substituted with the minimum signal value among the surrounding eight pixels of the same color.

Abstract: A process for performing white balancing of an image is performed by subdividing an image into a plurality of subframes, and then analyzing each subframe to determine if that subframe is predominantly monochromatic other than gray. If so, that subframe is excluded from the computation of the gain adjustments in the white balancing operation. As a result, the white balance process is performed using only the multicolored and/or gray subframes, thus allowing the overall white-balance of the image to be shifted only when a change in the color average is due to a change in the spectra of illumination, and not a presence of large monochromatic areas in the image.

Abstract: The integration time for an imager is adjusted to be an integer multiple of the light intensity received by the imager to reduce or eliminate flickering.

Abstract: Pixels from an image are sampled for auto white balance (AWB) statistics. To avoid the effects of monochromatic regions, pixels located at or near edges between monochromatic regions and neighboring regions are sampled for computation of the AWB gains. A sampling criteria is applied to each pixel that automatically excludes pixels in monochromatic regions of any size based on hue variances between pixels on the edges of the regions. As a result, white balancing is based on portions at or near edges of substantially monochromatic regions.

Abstract: A process for performing white balancing of an image is performed by subdividing an image into a plurality of subframes, and then analyzing each subframe to determine if that subframe is predominantly monochromatic other than gray. If so, that subframe is excluded from the computation of the gain adjustments in the white balancing operation. As a result, the white balance process is performed using only the multicolored and/or gray subframes, thus allowing the overall white-balance of the image to be shifted only when a change in the color average is due to a change in the spectra of illumination, and not a presence of large monochromatic areas in the image.

Abstract: A method and apparatus for accurately auto focusing a lens of an imaging device. In an exemplary embodiment, an imaged scene is split into an array of zones. The minimum and maximum sharpness score for each zone is determined over a plurality of lens positions. A histogram of the lens positions of the corresponding maximum sharpness score for each zone is created. The peak of the histogram is determined to be the best focus position for a given scene.

Abstract: A method for achieving flickerless operation of imagers using a rolling shutter, including the steps of detecting flicker in an image frame and adjusting an integration time such that the integration time is an integer multiple of a light intensity period, is described. The method reduces the task of detecting flicker to detecting a spatial sine wave in the image frame by subtracting two image frames from each other. The subtraction reduces or eliminates image content from the image frames and makes the detection process independent of image content. This method can be practiced based on a very short sequence of image frames (as few as two image frames) and is virtually insusceptible to motion of the image content. Adjustments to the integration time are made by changing the horizontal blanking time of the imager and, thereby extending the duration time of each row of said image frame.