Abstract: An upscaler is disclosed that upscales each of a maximum value map, a minimum value map and an average value map to a destination resolution. A blending module generates a detail-enhanced upscaled image of the source image having the destination resolution by blending corresponding pixel values from an upscaled image of the source image with at least one of: the upscaled maximum value map and the upscaled minimum value map. The blending may be based on the strength of detected edges in the source image and further based on a comparison of each pixel value in the upscaled image with a corresponding pixel value in an average value map. A source image characteristic calculator may generate the maximum value map, the minimum value map and the average value map based on the intensity values of a source image.

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: An image processing device includes a first image inputting unit, a second image inputting unit, an image processing unit, and a restriction control unit. The first image inputting that inputs a first image. The second image inputting unit inputs a second image. The image processing unit performs a prescribed process on the second image based on the first image. The restriction control unit is configured to restrict the prescribed process based on information of the first image.

Abstract: A method and apparatus for improved video bandwidth resolution in DFT-based spectrum analysis is disclosed. A first embodiment comprises an emulation of a continuous range of video bandwidths in DFT-based spectrum analysis using overlapping resolution bandwidth frames. A second embodiment utilizes frame weighting to reduce the standard deviation in the spectrum of noise signal to emulate a corresponding standard deviation of a specified video bandwidth.

Abstract: Methods and systems to determine a probability that a given illumination is a reference illumination. In an embodiment, data representing a set of respective captures of reference targets under a reference illumination may be used to generate a probability distribution for the reference illumination. In another embodiment, one or more such probability distributions, each corresponding to a respective reference illumination, may be used in estimating a non-reference illumination.

Abstract: An image encoding device includes a dynamic range generator for outputting dynamic range data Dd1 of block image data Dc1, an average value generator for outputting average value data De1 of the block image data Dc1, a number-of-pixel reducing unit 20 for decreasing number of pixels of the block image data by reduction-number of pixels to generate reduced-number-of-pixel block image data Dc1?, an encoding parameter generator 18 for generating encoding parameter pa1 specifying a quantization bit rate and the reduction-number of pixels in accordance with the dynamic range data Dd1, a quantization threshold generator 19 for generating a quantization threshold value tb1, and an image data quantizer 21 for generating quantized image data Df1 from the reduced-number-of-pixel block image data Dc1? with use of the quantization threshold value tb1.

Abstract: A dynamic gain adjustment method and apparatus based on brightness are provided. The dynamic gain adjustment method and apparatus amplify or attenuate high frequency components of an input video signal by dynamically varying a gain that is applied to a peaking algorithm block for picture quality improvement in a video processing device, such as a digital television, based on an average picture level (APL) of the input video signal. The gain can be dynamically adjusted when the APL of the input video signal is high or low, and thus saturation of the video signal during the operation of the peaking block can be prevented.

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: Systems and methods are provided for environment change sensing corresponding to the capsule camera entering the colon from the small intestine. In the environment change sensing mode, the capsule camera is operated in a very low power mode by configuring the image sensor to use a small region of interest or a high sub-sampling ratio. Image data is processed to estimate the light level. The variation of light level is used to detect environment change corresponding to entering the colon from the small intestine. Alternatively, the motion metric for a current frame and a reference frame is evaluated. The characteristic of the motion metric is extracted and used to detect environment change. In another configuration, the system determines environment change based on a combination of the variation of light intensity and the characteristic of the motion metric.

Abstract: The present invention provides a method and apparatus for filling Doppler signal gaps. The method comprises steps of: storing Doppler signals before and after a gap; analyzing spectral characteristics of the Doppler signals to be filled; judging whether the Doppler signals are to be frequency compensated according to the spectral parameters; compensating the Doppler signals; and filling the gap by means of weighting and superposing the frequency compensated Doppler signals to be filled and the original Doppler signals before and after the gap based on the judging result. According to the method of the present invention, the Doppler signals before and after the gap are first subjected to frequency compensation, and then weighted and superposed with the acquired Doppler signals, thus obtaining a continuous spectrogram and audio output and maintaining the original spectral characteristics of the Doppler signal.

Abstract: A method of processing image data comprises receiving input signals for specifying red, green and blue colors of the pixels of a display, performing a per-pixel low pass filtering of the input signals, the low pass filtering function being dependent on the chrominance variation between adjacent pixels, and providing the filtered output signals for use in driving the pixels of a display. This method essentially measures the chrominance variation of the incoming signal, in the form of the color change frequency, and depending on this variation, adaptively low-pass filters the incoming signal. This can be in such a way that the chrominance resolution of the outgoing signal is below the maximum chrominance resolution of the intended display, without errors in the average color of a small group of pixels.

Abstract: An image processing method corrects an original image. The method performs a retinex processing on a luminance signal of each pixel in an original image. The method determines, for each pixel, a retinex-processed pixel value based on the luminance signal that has been subjected to the retinex processing and at least one signal other than the luminance signal. The method generates a histogram by counting a rate of occurrence of the retinex-processed pixel values for each level over a predetermined first range of pixel values to which the retinex-processed pixel value is possibly assigned. The method reassigns each pixel value based on the histogram.

Abstract: A method for estimating kinetic parameters from image data includes using a processor to execute instructions for providing a model of kinetic contributions from first and second physiological regions; grouping voxels of the image data into first and second groups; determining an average value of the factors associated with the first group, the factors corresponding to blood-flow time activity curves; incorporating the average value of the factors associated with the first group into the model of kinetic contributions from the first and second physiological regions; and estimating the kinetic parameters based on the model of kinetic contributions.

Abstract: Provided are an apparatus and method of measuring a distance using structured light. The apparatus includes a binarization unit binarizing an image, an image identification unit identifying an image having connected pixels in the binarized image, a length ratio calculation unit obtaining the length ratio of the major axis of the image having the connected pixels to a minor axis perpendicular to the major axis, a pixel mean calculation unit obtaining the mean of pixel values of the image having the connected pixels, and an image extraction unit extracting an image formed by the light irradiated from the light source, from the images having connected pixels using the length ratio and the mean of the pixel values.

Abstract: Image enhancement techniques are described to enhance an image in accordance with a set of training images. In an implementation, an image color tone map is generated for a facial region included in an image. The image color tone map may be normalized to a color tone map for a set of training images so that the image color tone map matches the map for the training images. The normalized color tone map may be applied to the image to enhance the in-question image. In further implementations, the procedure may be updated when the average color intensity in non-facial regions differs from an accumulated mean by a threshold amount.

Abstract: A region of interest may be determined using any or all of sound source location, multi-person detection, and active speaker detection. An weighted mean may be determined using the region of interest and a set of backlight weight regions, or, only the set of backlight weight regions if a region of interest could not be found. The image mean is compared to a target value to determine if the image mean is greater than or less than the target value within a predetermined threshold. If the image mean is greater than the predetermined target value and predetermined threshold value, the gain and exposure are decreased. If the image mean is lesser than the predetermined target value minus the predetermined threshold value, the gain and exposure are decreased.

Abstract: An image processing apparatus includes a noise reduction unit which performs noise reduction processing to image signals, a first noise presumption unit which presumes a first noise amount from a present image signal among the image signals, and a second noise presumption unit which presumes a second noise amount based on the first noise amount, the present image signal, and the image signal of the past which underwent the noise reduction processing. The noise reduction unit performs the noise reduction processing to the present image signal based on the second noise amount.

Abstract: This invention describes an efficient super-resolution method for image enhancement that leverages prior knowledge about the specific task for which detail information is recovered. The particular case of barcode scanning is considered. The barcode localization and decoding algorithm of the present invention employs a subpixel-accurate search algorithm which allows for estimating barcode bit values at a higher resolution than that available in the image data itself. It thus allows for the synthesis of image detail from multiple frames with the result containing more detail than any of the input frames. For efficiency, it leverages special properties of the quadrilateral target object as well as prior knowledge about constant patterns in the barcodes of interest. This allows for real-time software implementations on portable devices such as camera-equipped cell phones where super-resolution helps to overcome some of the typical camera resolution and processing power constraints.

Abstract: A method and apparatus for reducing false color artifacts in digital images. Aperture correction and color saturation values are determined for a portion of an image surrounding a subject pixel. A color attenuation value is determined based at least in part on the aperture correction and color saturation values. A color value of the subject pixel is adjusted by an amount based at least in part on the color attenuation value. In one exemplary embodiment, the method and apparatus operate in the YUV color space and adjust U and V values of the subject pixel proportionally to the color attenuation value.

Abstract: Non-adjacent rows (i) in the visibility matrix (Msr) that have a large number of common elements are automatically detected (E7) and any such detected rows are permutated to put the lines detected as having a large number of common elements into sequence to form a modified visibility matrix (M?sr), and digital image coding is applied (E8) to the Boolean elements of the modified visibility matrix (M?sr).

Abstract: An anomaly detection method includes acquiring image data corresponding to nondestructive testing (NDT) of a scanned object. The NDT image data comprises at least one inspection test image of the scanned object and multiple reference images for the scanned object. The anomaly detection method further includes generating an anomaly detection model based on a statistical analysis of one or more image features in the reference images for the scanned object and identifying one or more defects in the inspection test image, based on the anomaly detection model.

Abstract: Computer-implemented image processing methods and apparatuses are presented for automatically selecting regions of interest within an image represented by pixel intensity values. A first pixel box is employed in progressively scanning and evaluating the image. If pixels within the first pixel box have pixel-intensity-related characteristics exceeding respective defined thresholds, then those pixels are identified as an area of interest and a second pixel box is employed in progressively scanning and evaluating the selected area of interest to identify regions of interest. Each area of interest is larger than a region of interest, and the second pixel box is smaller than the first. Regions of interest within the image are identified if one or more pixel-intensity-related characteristics of pixels within the second pixel box exceeds a second defined threshold, wherein the second threshold is greater than the first. Once selected, identifying information for the regions of interest is stored or output.

Abstract: The determination of an orientation of a finger touching a touch-sensitive device is disclosed. In one embodiment, a computing device comprises a display screen configured to display an image to a user, and an intensity-sensitive touch-sensing input mechanism configured to detect one or more objects touching the display screen. The device also comprises a controller configured to determine an orientation of a finger touching the screen from a direction between a center of a first set of touch data and a center of a second set of touch data, and to adjust an image on the display screen in response to a determined orientation of the finger.

Abstract: An image processing apparatus. First reducing means generates a first reduced size image by reducing an original image. Second reducing means generates a second reduced size image having a size larger than that of the first reduced size image and smaller than that of the original image by enlarging the first reduced size image. Red-eye correction means detects a red-eye position based on the second reduced size image and performs red-eye correction processing based on the detected red-eye position.

Abstract: An image processing method applied in an image processor for processing an image including first pixels each having a pixel value, a first reference pixel value representing a mean value of the pixel values of the first pixels, the pixel values of the first pixels being distributed within a first distribution range bounded between a second reference pixel value and a third reference pixel value. Second pixels are selected from the first pixels. The pixel values of the second pixels are distributed within a second distribution range. The second distribution range of the second pixels is smaller than the first distribution range of the first pixels. A local characteristic of the image is obtained according to the second pixels. A parameter of the image is adjusted according to the local characteristic.

Abstract: An image processing device includes: a parameter calculation unit that obtains a plurality of values based on a plurality of different conversion parameters for a pixel in image data; a weighting unit that performs predetermined weighting on the plurality of values obtained by the parameter calculation unit; and a gradation correction unit that performs gradation correction of the image data based on a result of the weighting by the weighting unit.

Abstract: An apparatus for picking up objects including a robot for picking up an object, at least one part of the object having a curved shape, having a storing means for storing a gray gradient distribution model of the object, a recognizing means for recognizing a gray image of the object, a gradient extracting means for extracting a gray gradient distribution from the gray image recognized by the recognizing means, an object detecting means for detecting a position or position posture of the object in the gray image in accordance with the gray gradient distribution extracted by the gradient extracting means and the gray gradient distribution model stored by the storing means, a detection information converting means for converting information of the position or position posture detected by the object detecting means into information of position or position posture in a coordinate system regarding the robot; and a robot moving means for moving the robot to the position or position posture converted by the detection

Abstract: Aspects of the disclosure provide a printing method that can utilize a lightly pigmented toner along with a darkly pigmented toner to improve the image quality. The method can include receiving a dataset corresponding to a printing of a printing system using a darkly pigmented toner. The printing system may have an undesirable optical density printing range for the darkly pigmented toner. Further, the method can include converting the dataset to a first dataset corresponding to a first printing of the printing system using the darkly pigmented toner, and a second dataset corresponding to a second printing of the printing system using a lightly pigmented toner. The first dataset can avoid the undesirable optical density printing range for the darkly pigmented toner, and a combination of the first printing and the second printing providing a substantially same printed optical density corresponding to the received dataset.

Abstract: Based on an area detection signal, a layer separation section outputs a text component of a document, to a feature point calculating section, and generates four layers from a pictorial component of the document to output the generated layers to the feature point calculating section. The feature point calculating section sums feature points extracted for each component. A features calculating section calculates a hash value based on the feature points. A vote processing section searches a hash table based on the hash value, and votes for a reference image associated with the hash value. Based on the voting result, a similarity determination processing section determines whether the document image is similar to any reference image, and then outputs the determination result. Thus, even if the document contains a photograph, accurate matching can be performed.

Abstract: A method and apparatus are provided for eliminating image noise to remove spatial-temporal noise and improve visibility. The method includes extracting a spatial-temporal noise level of neighbor pixels around a current pixel, filtering noise of the current pixel by applying a weight to spatial-temporal pixels around the current pixel based on the extracted spatial-temporal noise level, and applying a weight to the noise-filtered pixel and a boosted-up pixel based on an edge intensity and summing the weight-applied pixels. The spatial-temporal noise level is extracted based on spatial-temporal information of neighbor pixels around a current pixel in a current frame and spatial-temporal information of neighbor pixels around a current pixel in a previous frame.

Abstract: Methods of the present invention allow for optimization of color and shades of gray documents prior to their conversion to a monochrome format. If color/gray elements are identified in the document, the distance between them and their intensity is determined. If there are elements with the same or similar intensity in close proximity to each other, colors of some of the elements may be replaced with solid monochrome colors, and/or dithered surfaces, and/or monochrome patterns. Further, the elements may be outlined. These improvements make elements in the document more distinguishable after its conversion to a monochrome format. The described color optimization and outlining may have wide applicability in the Internet Fax technology.

Abstract: Methods of the present invention allow for optimization of color and shades of gray documents prior to their conversion to a monochrome format. If color/gray elements are identified in the document, the distance between them and their intensity is determined. If there are elements with the same or similar intensity in close proximity to each other, colors of some of the elements may be replaced with solid monochrome colors, and/or dithered surfaces, and/or monochrome patterns. Further, the elements may be outlined. These improvements make elements in the document more distinguishable after its conversion to a monochrome format. The described color optimization and outlining may have wide applicability in the Internet Fax technology.

Abstract: A method of and an apparatus for image enhancement taking ambient illuminance into consideration. The image enhancement method includes calculating an original-luminance contrast which is a luminance contrast with respect to an original-luminance of pixels forming an original image, calculating a fade-luminance by reflecting the variation of perceived luminance based on an ambient illuminance into the original-luminance, calculating a defade-luminance by converting the fade-luminance to maintain the original-luminance contrast, and calculating a display-luminance by reflecting the variation of perceived luminance by the ambient illuminance into the defade-luminance. Improving luminance contrast through adjustment of luminance based on ambient illuminance, effectively reduces the fade phenomenon.

Abstract: The invention discloses an image processing apparatus for adjusting lightness of an input image. The image processing apparatus includes a first processing module, a second processing module, a third processing module, and a fourth processing module. The first processing module is used for generating a lightness histogram with reference to the input image and determining a maximum lightness and an average lightness according to the lightness histogram. The second processing module is used for determining a first gain and a second gain according to the maximum lightness and a look-up table. The third processing module is used for selecting a lightness adjusting curve according to the average lightness. The fourth processing module is used for generating an output lightness corresponding to the input image.

Abstract: Provided are an apparatus and method for automatically adjusting luminance, and more particularly, apparatus and method for automatically adjusting luminance per region in plurality of luminance regions of an image to be displayed according to its average luminance value. An average luminance of an image is detected, and then contrast and brightness of image is automatically adjusted according to detected average luminance. Amplification of contrast and brightness is increased to brighten an image in an image with low luminance and reduced to suppress image dazzle in an image with high luminance, thereby providing user with an image of appropriate brightness, irrespective of original brightness. It is possible to prevent diversion of image by dividing its luminance level into a plurality of regions and controlling contrast and luminance per region. Further, a buffer region between luminance regions prevents flickering of image on a screen due to diversion of an adjustable gain.

Abstract: An object of the present invention is to provide an image processing apparatus capable of obtaining a sharp image having less noise, comprising: a horizontal edge strength calculating unit 22 for calculating an edge strength along a horizontal direction of a concerned pixel; and a prefilter 24 for carrying out a filter processing based on the horizontal edge strength, and performing noise reduction and edge enhancement, a vertical edge strength calculating unit 23 for calculating an edge strength along a vertical direction of the concerned pixel; and a prefilter 25 for carrying out a filter processing based on the vertical edge strength, and performing noise reduction and edge enhancement, thereby enabling to sharpen image data in the vicinity of the concerned pixel respectively along horizontal and vertical directions, and obtain an image having less noises as well as sharp for edge directions.

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: Sub-pixel rendering with gamma adjustment allows the luminance of the sub-pixel arrangement to match the non-linear gamma response of the human eye's luminance channel. For each of a subset of input sampled data indicating a region of an input image, a gamma-adjusted data value is generated for each input image data value in the subset using a local average of at least two input image data values. A sub-pixel rendering operation uses the subset of gamma-adjusted data values and the subset of input image data values to produce an output data value for each sub-pixel element on the display panel. A plurality of output data values collectively indicates an output image. The gamma adjustment allows the sub-pixel rendering to operate independently of the actual gamma of a display device. The sub-pixel rendering techniques with gamma adjustment may improve image contrast in high spatial frequency portions of an image.

Abstract: An input gradation converting circuit has a gradation conversion table in which M-bit intermediate gradation data are correlated with each of N-bit input gradation data, and is operable to convert each of the input gradation data into the M-bit intermediate gradation data by using the gradation conversion table and output the converted M-bit intermediate gradation data. A diffusion gradation converting circuit is operable to convert each of the intermediate gradation data outputted from the input gradation converting circuit into N-bit output gradation data and output the converted N-bit output gradation data. The diffusion gradation converting circuit acquires a uniform random number Rnd in the range of ?SFT/2 to SFT/2 and outputs [X+Rnd+0.5] as the output gradation data for each of the intermediate gradation data in which X obtained by dividing a value of the intermediate gradation data by 2M·N and a specified value SFT satisfy a conditional expression “SFT/2?[X]?2N?1?SFT/2” (where [ ] is a Gauss symbol).

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 luminance intensity of pixels of an input digital image is corrected for generating a corrected digital image. A luminance of each pixel is calculated as a function of the luminance of a corresponding pixel in an original image according to a parametric function. A mask of the input digital image to be corrected is generated according to a bilateral filtering technique. For each pixel of the input digital image, a respective value of at least one parameter of the parametric function is established based upon the luminance of a corresponding pixel of the mask.

Abstract: A system comprising a storage including an image file associated with a plurality of pixels and processing logic coupled to the storage. The processing logic is adapted to determine an average of least significant bits associated with a maximum of two of the plurality of pixels, add the average to bits associated with a target pixel, and disassociate from the target pixel least significant bits of the target pixel. No pixels are disposed between the target pixel and each of the two of the plurality of pixels.

Abstract: A method, apparatus, and computer usable program code for signal-to-noise enhancement. In one illustrative embodiment, a system is provided for signal-to-noise enhancement. The system includes a rank order filter and a comparator. The comparator receives an ordered set of data values from the rank order filter. A signal averager averages a subset of data values selected from the ordered set of data values by the comparator.

Abstract: A method for enhancing an ultrasound image is provided, wherein the ultrasound image is segmented into a feature region and a non-feature region, while sufficiently utilizing features contained in the ultrasound image, in particular including some inconspicuous features, the enhanced image according to present invention is not susceptive of the image segmentation and avoid dependence of the enhancement effect on the segmentation template, so as not to produce an evident artificial boundary between the feature region and the non-feature region but to highlight some special information in the image and to remove or mitigate invalid information. Thus the enhanced ultrasound image is particularly suitable for the visual system of the human beings.

Abstract: A method for enhancing an ultrasound image is provided, wherein the ultrasound image is segmented into a feature region and a non-feature region, while sufficiently utilizing features contained in the ultrasound image, in particular including some inconspicuous features. The enhanced image according to present invention is not susceptive of the image segmentation and avoid dependence of the enhancement effect on the segmentation template, so as not to produce an evident artificial boundary between the feature region and the non-feature region but to highlight some special information in the image and to remove or mitigate invalid information. Thus the enhanced ultrasound image is particularly suitable for the visual system of the human beings.

Abstract: The present disclosure provides methods and systems for image processing by locally adaptive filters that preserve the edges while smoothing the image. In the exemplary method, a filter adjusts image pixel values utilizing a locally adaptive weighted average method. To adjust the value of a target pixel, the filter uses the data corresponding to some of its surrounding pixels and modifies the weights in an inverse relation with both their distance from the target pixel and the difference between their data. Various embodiments present different schemes for selection of surrounding pixels and computation of weighted average values.

Abstract: It is intended to provide a picture editor which displays the color pictorial data matching designated pictorial information, according to pictorial information code of the analyzed color pictorial data of a plurality of color pictures added to the color pictorial data, picks out and displays the color pictorial data matching designated pictorial information. For this purpose, the information code of each pictorial information on brightness, saturation, and hue of the color pictorial data, which is analyzed, digitized, and averaged in a pictorial data analyzing unit, is added to the color pictorial data in a retrieval information adding unit. According to the color pictorial data to which the information code is added, a retrieving unit picks out the color pictorial data matching designated pictorial information. A video monitor displays the retrieved color pictorial data.

Abstract: The invention provides for a method of sharpening an image to be sent to a printhead. The method includes the steps of receiving an RGB (red, green, blue) data set indicative of the image, and deriving an initial luminance channel from the received data set. The method also includes the steps of sharpening the initial luminance channel to form a revised luminance channel, and incorporating the revised luminance channel into the data set.

Abstract: The AC and/or PC landmarks are identified in a midsagittal MRI image by firstly identifying structures in the brain (specifically the fornix and/or brainstem) as groups of pixels in a radiological image which have an intensity in ranges defined by one or more thresholds and which obey predefined geometrical criteria. The thresholds are varied until the predefined geometrical criteria are met. Initial estimates of the position of the AC and/or PC are derived from the identified structures. These estimates can be improved in various ways, especially by making use of axial and/or corona/radiological images in planes including, and/or proximate to, the initial estimated position of the AC and/or PC.

Abstract: The invention relates to a method and a device for processing a mosaic of noisy source images exhibiting overlap zones where at least two of the source images are superimposed. According to the invention, the method comprises a step of generating a random noise (35) in the overlap zones so as to compensate at least partially for the deviation in noise between the overlap zones and the zones where the source images are not superimposed, called non-overlap zones.