Abstract: In one embodiment, a method of amplifying temporal variation in at least two images includes converting two or more images to a transform representation. The method further includes, for each spatial position within the two or more images, examining a plurality of coefficient values. The method additionally includes calculating a first vector based on the plurality of coefficient values. The first vector can represent change from a first image to a second image of the at least two images describing deformation. The method also includes modifying the first vector to create a second vector. The method further includes calculating a second plurality of coefficients based on the second vector.

Abstract: Techniques for presenting insight into classification trees may include performing a grouping analysis to group leaf nodes of a classification tree into a significant group and an insignificant group, performing influential target category analysis to identify one or more influential target categories for the leaf nodes of the classification tree in the significant group, and presenting one or more insights into the classification tree based on the grouping analysis and the influential target category analysis. Techniques for presenting insight into regression trees may include performing a grouping analysis to group leaf nodes of a regression tree into a high group and a low group, performing unusual node detection analysis to detect one or more outlier nodes in the high group and in the low group, and presenting one or more insights into the regression tree based on the grouping analysis and the unusual node detection analysis.

Abstract: An image sensing apparatus, a color-correction matrix correcting method and a look-up table establishing method are provided. The image sensing apparatus calculates a block statistics value corresponding to a block of pixels in an image sensor array. Based on a look-up table, the image sensing apparatus determines a covariance value corresponding to a current gain value. According to the covariance value and the block statistics value, the image sensing apparatus corrects a color-correction matrix corresponding to the block of pixels. The image sensing apparatus can use an amended color-correction matrix to correct the color of the pixel, so as to reduce chroma noise or other noise.

Abstract: An object detection device includes an acquisition unit configured to acquire information indicating a temperature distribution, a storage unit configured to store background information indicating a temperature distribution when no target object exists, a detection unit configured to detect existence or absence of a target object, and an update unit configured to repeatedly update the background information. The update unit performs, with respect to a non-detection region, a first background updating process for the update of the background information based on the acquired information and performs, with respect to a detection region, a second background updating process for the update of the background information using a correction value.

Abstract: Disclosed are a magnetic resonance imaging (MRI) apparatus and method. The MRI apparatus includes a data acquirer, which performs under-sampling of MR signals, respectively received from a plurality of channel coils included in a radio frequency (RF) multi-coil, at non-uniform intervals to acquire a plurality of pieces of line data, and an image processor that restores a plurality of pieces of K-space data respectively corresponding to the plurality of channel coils by using a relationship between the acquired plurality of pieces of line data, thereby restoring an MR image with reduced aliasing artifacts.

Abstract: Provided is a touch panel with improved anti-noise performance. A continuous drive pulse train is input to a plurality of scanning electrodes for each one scanning period in turns, and a detection pulse train generated at detection electrodes which intersects the scanning electrodes is detected. The detection pulse train is sampled at different intervals to generate a plurality of data sequences. The plurality of data sequences may be generated from the detection pulse train over a plurality of frame periods. A signal strength of each frequency component is compared between the frequency spectra of the plurality of data sequences, and a frequency spectrum in which frequency components having different strengths have been corrected is generated. A detection signal is generated from the corrected frequency spectrum.

Abstract: Systems and methods for authenticating a document are provided. In one embodiment, a method for authenticating a feature of a document includes capturing a first image of a region of a document while the region is subjected to a first wavelength of electromagnetic radiation. The region includes at least a portion of the document. The method also includes determining a first intensity value associated with the first image of the region, and comparing the first intensity value with a first training intensity value of a region of a training document. The first training intensity value is obtained using the first wavelength of electromagnetic radiation. The method also includes determining whether the document is authentic at least partially based on the comparison between the first intensity value and the first training intensity value.

Abstract: A converted reference image generated from a reference image is searched for a first corresponding point corresponding to a first standard point included in a converted standard image generated from a standard image. Based on a position of the first corresponding point in the converted reference image, a second search standard point is determined on the reference image. Further, based on phase information on each frequency component regarding a second standard area including a second standard point corresponding to the first standard point of the standard image, and based on phase information on each frequency component regarding a second reference area including the second search standard point of the reference image, the reference image is searched for a second corresponding point corresponding to the second standard point. The information on a frequency component obtained in the computation on another stage is reused in the search on the two stages above.

Abstract: A method for correcting overfocus of a digital image created from coherent imaging using centered fractional Fourier transforms or mathematical equivalents is described. A received image is presented to a numerical processor, and a first numerical value for an imaginary power variable is selected and used in an iterative algorithm, numerical procedure, system architecture, etc. A centered discrete fractional Fourier transform of an imaginary power and a phase restore operator associated are applied to the image file to produce a modified image. A change in mis-focused is determined and used in adjusting the specified imaginary power for a next iteration.

Abstract: A method of performing an image retargeting quality assessment comprising comparing an original image and a retargeted image in a frequency domain, wherein the retargeted image is obtained by performing a retargeting algorithm on the original image. The disclosure also includes an apparatus comprising a processor configured to perform an image retargeting quality assessment, and compare an original image and a retargeted image in a spatial domain, wherein the retargeted image is obtained by performing a retargeting algorithm on the original image, and wherein comparing the original image and the retargeted image in the spatial domain comprises comparing the original image and the retargeted image to determine an amount of shape distortion between the images.

Abstract: A light array includes lights that transmit modulated light to indicate their unique light identifiers (IDs) and lights that transmit unmodulated light. A light receiver records images of the light array and recovers the light IDs from the modulated light. The light receiver uses the IDs to retrieve a light map representative of the light array. The receiver aligns the retrieved light map with the recorded images of the light array, and accesses real-world positions of all of the light in the light array, as deployed, based on the aligned light map. The light receiver determines a 3-dimensional position of the light receiver relative to the light array.

Abstract: In selected embodiments, improved image restoration is realized using extensions of Wiener filtering combined with multiple image captures acquired after simple, fast reconfigurations of an optical imaging system. These reconfigurations may yield distinct OTF responses for each capture. The optical imaging system may reduce fabrication cost, power consumption, and/or system weight/volume by correcting significant optical aberrations. The system may be configured to perform independent correction of fields within the total field-of-regard. The system may also be configured to perform independent correction of different spectral bands.

Abstract: Reference-free compensated imaging makes an estimation of the Fourier phase of a series of images of a target. The Fourier magnitude of the series of images is obtained by dividing the power spectral density of the series of images by an estimate of the power spectral density of atmospheric turbulence from a series of scene based wave front sensor (SBWFS) measurements of the target. A high-resolution image of the target is recovered from the Fourier phase and the Fourier magnitude.

Abstract: A method of modifying the blur in at least a part of an image of a scene captures at least two images of the scene with different camera parameters to produce a different amount of blur in each image. A corresponding patch in each of the captured images is selected each having an initial amount of blur is used to calculate a set of frequency domain pixel values from a function of transforms of the patches. Each of the pixel values in the set are raised to a predetermined power, forming an amplified set of frequency domain pixel values. The amplified set of frequency domain pixel values is combined with the pixels of the patch in one of the captured images to produce an output image patch with blur modified relative to the initial amount of blur in the image patch.

Abstract: Methods, systems and computer program products for managing frequency domain optical coherence tomography (FDOCT) image resolution. A spectrum used to acquire an image of a subject is calibrated and default dispersion correction parameters are set. Default dispersion management parameters associated with a region of the image of the subject are also set. The image of the subject is acquires after setting the default dispersion correction parameters and the default dispersion management parameters. A quality of the acquired image is compared to a quality metric for the acquired image. The dispersion correction parameters are adjusted if the quality of the acquired image does not meet or exceed the quality metric for the acquired image. The acquired image is reprocesses based on the adjusted dispersion correction parameters. The steps of comparing, adjusting and reprocessing are repeated until the acquired image meets or exceeds the quality metric for the acquired image.

Abstract: A method for recognition of a predetermined pattern in an image data set recorded by a device for recording of at least two electromagnetic frequency spectra is provided. A first difference value is formed for the image points of the selected area as a function of a difference between a data vector of a corresponding image point and a first reference data vector. A second difference value is formed for an image point of a selected area as a function of a difference between the data vector of this image point and a second reference data vector. A predetermined pattern is recognized when it is determined at least one pattern correlation quantity is below a predetermined threshold value and a local minimum is present.

Abstract: The skew angle of a document image is determined or estimated. The skew angle is determined or estimated by examining patterns found within a Fast Fourier Transform of a subset of the document image. This technique exploits the internal structure of the document designs to allow fast and accurate skew angle estimation, including for arbitrary document fragments.

Abstract: A method (300) is described of determining characteristic of an ink jet printer (15). A chart containing multiple regions or patches is printed (320) on a print medium (115) using the ink jet print (15). The chart includes at least a first region printed using a first set of nozzles, and at least a second region printed using a second set of nozzles. The first and second sets of nozzles are a predetermined distance apart in the printer head of the printer (15). The printing of the first and second regions is also separated by a print medium advance operation equal to the predetermined distance. This causes the first and second regions to be aligned in the direction of the print medium advance operation. The chart is then imaged using scanner (16) chart to form a chart image. The positions of the regions appearing in the chart image are next determined (340).

Abstract: An MR system compensates for patient movement by generating a magnetic field for acquiring, first data representing individual frequency components of a segment of a k-space storage array during a first time period and second data representing individual frequency components of the segment of the k-space storage array during a subsequent second time period. The first and second data comprise individual frequency components of different images of a portion of the anatomy of a patient. The system uses the first and second data in calculating a measure representing degree of patient related motion occurring between acquisition of the first data and second data and generates an image by excluding frequency components of the first data and second data in response to the calculated measure exceeding the predetermined threshold value.

Abstract: Computer-implemented arrangements for adjusting the focus in original electron microscope image data are described. In an implementation, a fractional Fourier transform operation and a phase restoration operation, both responsive to a fractional power, are collectively applied to original electron microscope image data to produce computationally-focused image data. A parameter adjuster is used to provide a range of variation of the power, and can be adjusted by a user or under the direction of a control system. The fractional Fourier transform operation and the phase restoration operation can be realized by at least one numerical algorithm and can comprise an approximation.

Abstract: Estimating focus error in an image involves a training phase and an application phase. In the training phase, an optical system is represented by a point-spread function. An image sensor array is represented by one or more wavelength sensitivity functions, one or more noise functions, and one or more spatial sampling functions. The point-spread function is applied to image patches for each of multiple defocus levels within a specified range to produce training data. Each of the images for each defocus level (i.e. focus error) is sampled using the wavelength sensitivity and spatial sampling functions. Noise is added using the noise functions. The responses from the sensor array to the training data are used to generate defocus filters for estimating focus error within the specified range. The defocus filters are then applied to the image patches of the training data and joint probability distributions of filter responses to each defocus level are characterized.

Abstract: Computer-implemented arrangements for adjusting the focus in original electron microscope image data are described. In an implementation, an origin-centered fractional Fourier transform operation and an origin-centered phase restoration operation, both responsive to a provided fractional power value, are collectively applied to original electron microscope image data to produce computationally-focused image data. A parameter adjuster is used to provide a range of variation of the power value, and can be adjusted by a user or under the direction of a control system. The fractional Fourier transform operation and the phase restoration operation can be realized by at least one numerical algorithm and can comprise an approximation.

Abstract: Image processing apparatus includes: interpolation process image acquisition means for acquiring an interpolation process image of prescribed size which includes an interpolation point of an inputted image; Fourier transform means for subjecting the interpolation process image which is acquired with the interpolation process image acquisition means to Fourier transform; phase change means for changing, a phase of each value of the transformed interpolation process image which has been subjected to Fourier transform by the Fourier transform means, such that the interpolation point migrates to a desired nearby integer coordinate position; inverse Fourier transform means for subjecting the interpolation process image whose phase has been changed by the phase change means, to inverse Fourier transform; interpolation value determination means for adopting an interpolation point, a value of a pixel at the integer coordinate position, from the transformed interpolation process image subjected to inverse Fourier tran

Abstract: A 3D ultrasound image from a memory is compared with a 3D diagnostic image from a memory by a localizer and registration unit which determines a baseline transform which registers the 3D diagnostic and ultrasound volume images. The target region continues to be examined by an ultrasound scanner which generates a series of real-time 2D or 3D ultrasound or other lower resolution images. The localizer and registration unit compares one or a group of the 2D ultrasound images with the 3D ultrasound image to determine a motion correction transform. An image adjustment processor or program (operates on the 3D diagnostic volume image with the baseline transform and the motion correction transform, to generate a motion corrected image that is displayed on an appropriate display.

Abstract: A method, computer program product, and apparatus for displaying a calculated geometric entity within at least one 3D range data set obtained using a 3D rangefinder device. At least a first 3D range data set is provided. Each 3D range data set is displayed as at least one displayed image. A calculated geometric entity that represents a non-physical entity is specified. The calculated geometric entity is displayed merged within at least one displayed image, where the calculated geometric entity represents something other than the physical objects represented by the first 3D range data set.

Abstract: Method for collecting video files of one or more Leak Detection and Repair (LDAR) components, including receiving information pertaining to the one or more LDAR components within a specified area, recording a video of the LDAR components for a predetermined amount of time using a camera, associating the video with the information, and storing the video along with the information to a memory located in a computer.

Abstract: A method of selecting an optimal window length in a digital processing system includes receiving a digital signal and analyzing the signal with a group of Hanning windows having different sizes. The windows being arranged so that they can be scaled to be comparable. The digital signal is windowed with each selected window and a transform is computed. The transformed signal is scaled and corrected. A metric is computed from the resulting signal for each window. The metrics are compared and the window size is selected based on agreement with a user defined metric. The specific window function, shift and scaling are such that the resulting analysis is mathematically equivalent across different window sizes.

Abstract: Some aspects include a method and apparatus for detecting image impairments caused by interpolation in an output image interpolated from two or more input images. The method comprises applying a substantially shift invariant transform to the interpolated image and to at least one of the input or adjacent images to derive a transformed image representation for each image. The transformed image representations of the interpolated image and the at least one adjacent image are then compared and differences between the transformed image representations indicative of image impairments in the output image caused by interpolation are determined based on the results of the comparison.

Abstract: An image processing apparatus that performs an image restoration processing of an image includes an optical transfer function obtaining portion configured to obtain an optical transfer function depending on an image pickup condition of the image, a threshold frequency obtaining portion configured to obtain a threshold frequency at which an absolute value of the optical transfer function is under a predetermined threshold value, a generating portion configured to generate an image restoration filter that has gain characteristics depending on the threshold frequency using the optical transfer function, and a processing portion configured to perform the image restoration processing of the image using the image restoration filter.

Abstract: A method of improving accuracy and reliability of motion estimation is described herein. In one aspect, a 2D neighborhood of phase correlation peak is approximated with an outer-product of two 1D vectors to eliminate the sub-pixel error. In another aspect, estimation of reliability is improved. In yet another aspect, two-pass phase correlation is implemented to eliminate sub-pel motion bias.

Abstract: An image processing apparatus includes a memory configured to store information of an OTF or a PSF of an optical system for at least one of capturing conditions, and an image processor configured to generate secondary and higher components of a phase of an OTF or a shape component of a PSF corresponding to a capturing condition of a captured image through an interpolation based on at least two OTFs or PSF in the memory, while center-of-gravity positions or maximum intensity positions are accorded with each other or differential root-mean-square values of the point spread functions are minimum, and to restore the image utilizing the generated OTF or an OTF derived from the generated PSF.

Abstract: An embodiment of a method for computing pyramids of input images (I) in a transformed domain, e.g., for search and retrieval purposes, includes:—arranging input images in blocks to produce input image blocks,—subjecting the input image blocks to block processing including: transform into a transformed domain, subjecting the image blocks transformed into a transformed domain to filtering, subjecting the image blocks transformed into a transformed domain and filtered to inverse transform implementing an inverse transform with respect to the previous transform into a transformed domain, thus producing a set of processed blocks. The set of processed blocks, which is recomposeable to an image pyramid, may be used, e.g., in detecting extrema points in images in the pyramid, extracting a patch of given size around the extrema points detected, and processing the patch to obtain local descriptors such as SIFT descriptors of a feature.

Abstract: Systems and methods for imaging a 3D volume of geometrically irregular grid data. The systems and methods utilize various types of probes and displays to render the geometrically irregular grid data, in real-time, and analyze the geometrically irregular grid data.

Abstract: Methods, storage mediums and systems (MS&S) are provided which successively image an imaging region of an assay analysis system (AAS) as particles are loaded into the imaging region, generate a frequency spectrum of each image via a discrete Fourier transform, integrate a same coordinate portion of each frequency spectrum and terminate the loading of particles upon computing an integral which meets preset criterion. In addition, MS&S are provided which send a signal indicative of whether enough particles are in an imaging region for further processes by an AAS based on the magnitude of integral calculated from an image's frequency spectrum. MM&S are also provided such that the steps of generating a frequency spectrum of each image and integrating a portion of each frequency spectrum are replaced by generating a convolved spatial image with a filter kernel and integrating a same coordinate portion of each convolved spatial image.

Abstract: Methods for numerically generating a centered discrete fractional Fourier transform matrix on a computer, the centered discrete fractional Fourier transform matrix of size N by N where N is an odd integer. Centering is obtained by simple barrel roll operations on eigenvectors. High-accuracy is obtained by numerically calculating the eigenvectors of the discrete fractional Fourier transform matrix from a closed-form mathematical formula and then iteratively performing a Gram-Schmidt orthogonalization procedure until a resulting set of improved-orthogonal eigenvectors is produced that is sufficiently orthogonal.

Abstract: A method for removing cyclic noise from a borehole image includes transforming the image into the frequency domain using a two-dimensional (2-D) transform (e.g., using a discrete cosine transform). The cyclic noise components (peaks) are removed from the transformed image which is then inverse transformed back into the spatial domain using an inverse 2-D transform to obtain a corrected image. An automated method enables the cyclic peaks to be identified and removed from the borehole image via downhole processing.

Abstract: A method of evaluating a composite structure in which a portion of the structure is imaged and subsequently transformed to provide a 2D output of the angular distribution of features, eg a 2D FFT. A weighting function is applied to the output to compensate for variation in the angular density of pixel population. The weighted output is then used to provide an angular distribution of feature intensity. The structure can be imaged in two or more intersecting planes to allow a 3D determination of feature direction to be obtained.

Abstract: A learning technique is provided that learns how to process images by exploiting the spatial and spectral correlations inherent in image data to process and enhance images. Using a training set of input and desired output images, regression coefficients are learned that are optimal for a predefined estimation function that estimates the values at a pixel of the desired output image using a collection of similarly located pixels in the input image. Application of the learned regression coefficients is fast, robust to noise, adapts to the particulars of a dataset, and generalizes to a large variety of applications. The invention enables the use of image sensors with novel color filter array designs that offer expanded capabilities beyond existing sensors and take advantage of typical high pixel counts.

Abstract: A system and method processes intensity images having a ring structure to measure position, shape deviation and/or radius of the ring structure, and to evaluate interferograms and/or localize objects. The system and method can define N sectors of the intensity image respectively having sector tips lying at a common sector origin within the ring structure, with N being a natural number where N>1, detect a distance of an intensity extreme from the respective sector tip of each sector of at least one group of the sectors to obtain a distance vector that includes the distances from all the sectors from at least the group of the sectors, perform a Fourier transformation of the distance vector, and determine a center, a radius and/or a deviation of the ring structure from a circular shape,-by using the first Fourier vector obtained by the Fourier transformation.

Abstract: Systems, methods, and computer-readable storage media for editing the frequency content of an image may provide an intuitive interface for examining and/or modifying the frequency content. The methods may include accessing image data, performing a wavelet transform of the image data (or another MRA technique) to produce a time-frequency representation (TFR) of the image representing frequency content in multiple frequency bands, and displaying an indication of the frequency content of the image by displaying a sub-image of the TFR or numerical data representing the frequency content at selected pixels. In response to receiving input specifying a desired frequency content modification, the methods may include performing a Fourier transform of the image data to produce frequency content data, modifying the frequency content data, and performing an inverse transformation of the modified data to produce modified image data. The modification may be applied globally or to a selected portion of the image.

Abstract: A method and system for improving picture quality of color images by combing the content of a plurality of frames of the same subject; comprising: at least one processor; the at least one processor comprising a memory for storing a plurality of frames of a subject; the at least one processor operating to combine the content of plurality of frames of the subject into a combined color image by performing: a process in which at least two multicolored frames are converted to monochromatic predetermined color frames; a gross shift process in which the gross shift translation of one monochromatic predetermined color frame is determined relative to a reference monochromatic predetermined color frame; a subpixel shift process utilizing a correlation method to determine the translational and/or rotational differences of one monochromatic predetermined color frame to the reference monochromatic predetermined color frame to estimate sub-pixel shifts and/or rotations between the frames; and an error reduction process to

Abstract: A method and apparatus for preparing a digital hologram representing an image of an object includes generating a measurement beam and a first reference beam, irradiating the object by the measurement beam, and guiding the measurement beam reflected to an optical sensor. The method also includes guiding the first reference beam to a first mirror, and guiding the reflected beam to the optical sensor so that both beams generate an interference pattern on the sensor. The method includes providing a digital signal representing the interference pattern on the optical sensor, to obtain a digital hologram, and subjecting the digital hologram to a Fourier transform in the spatial frequency domain to obtain a spectrum. The method further includes replacing a section of a first image term overlapped by a DC-term by a corresponding section of a second image term.

Abstract: A method for removing cyclic noise from a borehole image includes transforming the image into the frequency domain using a two-dimensional (2-D) Fourier Transform, removing cyclic noise components from the transformed image, and inverse transforming the image back into the spatial domain using an inverse 2-D Fourier Transform. The cyclic noise component may also be isolated by subtracting the corrected image from the original image or by removing all non-cyclic noise components from the transformed image prior to inverse transforming. Removal of the cyclic noise from a borehole image tends to enable the identification of borehole features and provide for improved accuracy in formation parameter evaluation. Evaluation of the cyclic noise component may also enable the source of the noise to be identified and mitigated.

Abstract: A method of deriving a representation of an image by processing signals corresponding to the image, the method comprises deriving a function of the image, where a function of a translated, scaled or rotated version of the image is a translated or scaled version of the derived function of the image, and using a plurality of frequency components of a frequency representation of the function to derive a representation of the image.

Abstract: Provided are a method and apparatus for transforming an image, in which an input image is transformed into a frequency domain by selectively using a plurality of frequency transform algorithms according to a frequency characteristic of the input image. The method includes: selecting a frequency transform algorithm to be used for a current block from a plurality of frequency transform algorithms according to a result obtained by transforming frequencies of peripheral blocks adjacent to the current block; and transforming the current block into a frequency domain by using the selected frequency transform algorithm.

Abstract: Methods, systems and computer program products for managing frequency domain optical coherence tomography (FDOCT) image resolution. A spectrum used to acquire an image of a subject is calibrated and default dispersion correction parameters are set. Default dispersion management parameters associated with a region of the image of the subject are also set. The image of the subject is acquires after setting the default dispersion correction parameters and the default dispersion management parameters. A quality of the acquired image is compared to a quality metric for the acquired image. The dispersion correction parameters are adjusted if the quality of the acquired image does not meet or exceed the quality metric for the acquired image. The acquired image is reprocesses based on the adjusted dispersion correction parameters. The steps of comparing, adjusting and reprocessing are repeated until the acquired image meets or exceeds the quality metric for the acquired image.

Abstract: The present invention discloses methods for lossless shearing and/or rotation of two-dimensional (2D) data, including digital images, with minute discrete angular increments, carried out only by permutations in the Fourier frequency domain, by exploiting the natural shear occurring as a result of computing a single one-dimensional discrete Fourier transform (DFT) of 2D arrays. Rotations in general, especially for oblong arrays, occur on elliptical paths. Circular rotation, by an angle of arctan(1/width), is achieved on square arrays. When each dimension is multiple of a smaller N, the rotation/shear angle can be increased to arctan(2N/width). Rotation steps can be repeated in long, animation-like series, with neither loss nor degradation of the Fourier content; so much so that tracing the steps back does restore the original data with remarkable precision.

Abstract: A system and method for projection number and radiation dose reduction in tomographic imaging that creates a three dimensional cross sectional image of an object by the reconstruction of its projections. Images of a superior quality can be obtained with a fewer number projections than seen with conventional methods by reconstruction of projections that have been pre-processed and preferably placed in the Fourier domain with a Fractional Fourier Transform (FrFT) or forward Pseudo-polar Fast Fourier transform (PPFFT). The projections are iteratively refined through formulation of a constrained optimization problem with constraints in object space and Fourier space preferably solved with a gradient descent algorithm incorporating a Bregman iterative regularization or a continuative regularization.

Abstract: An optical processing system is described that allows rapid evaluation of derivatives and partial derivatives by means of optical Fourier transformation. In embodiments, separate filtering steps are used to provide phase and amplitude changes.

Abstract: Various methods and apparatus for removing artifacts in frequency domain processing of light-field images are described. Methods for the reduction or removal of the artifacts are described that include methods that may be applied during frequency domain processing and a method that may be applied during post-processing of resultant angular views. The methods may be implemented in software as or in a light-field frequency domain processing module. The described methods include an oversampling method to determine the correct centers of slices, a phase multiplication method to determine the correct centers of slices, a method to exclude low-energy slices, and a cosmetic correction method.