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updated 9 months ago

Rotate images with automatic cropping by David Young

David Young (view profile)

The blank triangles that appear in the corners of rotated images are cropped away. (image processing, rotate image, crop image)

checkattributes(a, classes, attributes)

imRotateCrop(im, theta, varargin)

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updated 10 months ago

Gradients with Gaussian smoothing by David Young

David Young (view profile)

Grey-level gradients are estimated using Gaussian smoothing followed by symmetric differencing. (image processing, image smoothing, gaussian smoothing)

checkattributes(a, classes, attributes)

exindex(arr, varargin)

gradients_n(a, varargin)

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updated 12 months ago

Hough transform for circles by David Young

David Young (view profile)

A Hough transform function for detecting circles, optimised to allow search over radii. (hough transform, circle, image analysis)

Circular Hough Transform Demonstration

circle_hough(b, rrange, varargin)

circle_houghpeaks(h, radii, varargin)

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updated 1 year ago

A multidimensional map class by David Young

David Young (view profile)

MapN provides a map class similar to containers.Map, but with multidimensional keys. (map, container, containers)

memoize(f)

MapN

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updated 1 year ago

Fast 2-D convolution by David Young

David Young (view profile)

Speeds up many 2-D convolutions using the SVD; also finds a fast approximation in other cases. (2d, convolution, filtering)

convolve2(x, m, shape, tol)

exindex(arr, varargin)

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updated 1 year ago

TerraSAR-X and TanDEM-X tools by David Young

David Young (view profile)

Read and convert TerraSAR-X and TanDEM-X COSAR files (sar, insar, synthetic aperture ra...)

TD2TSall(d)

TanDEM2TerraSAR(filein, fileout)

allfiles(d, ext)

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updated 1 year ago

Canny edge detection in 2-D and 3-D by David Young

David Young (view profile)

A Canny edge detector for two-dimensional image and three-dimensional volume data. (canny, edge detection, 3d)

canny(im, varargin)

checkattributes(a, classes, attributes)

exindex(arr, varargin)

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updated 1 year ago

emptyStruct by David Young

David Young (view profile)

Creates empty struct arrays of various kinds (structures, structure, struct)

emptyStruct(fieldnames, sz)

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updated 1 year ago

Max and min keeping NaNs by David Young

David Young (view profile)

The max and min functions ignore NaN values. These functions keep them like arithmetic functions do. (max, min, maximum)

maxNan(a, b, dim)

minNan(a, b, dim)

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updated 3 years ago

Image correspondences using cross-correlation by David Young

David Young (view profile)

Find matching features in pairs of images using normalised cross-correlation: class file and demo. (image analysis, optic flow, optical flow)

Image correspondence by cross-correlation demonstration

convolve2(x, m, shape, tol)

correspDisplay(corresps, im, col)

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updated 3 years ago

Affine optic flow by David Young

David Young (view profile)

Estimates the parameters of an affine (first-order) optic flow model from two images. (optic flow, optical flow, affine)

Affine Optic Flow Demonstration

affine_flowdisplay(flow, im, step, col)

affine_flowedgedisplay(flow, im1, im2)

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updated 3 years ago

Extended Brookshear Machine emulator and assembler by David Young

David Young (view profile)

Emulator and assembler for a simple computer, a teaching aid for computer science courses. (machine code, assembler, gui)

Extended Brookshear Machine Assembler

Extended Brookshear Machine Emulator

assembler(file)

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updated almost 4 years ago

Logarithm of complex sine and cosine avoiding overflow by David Young

David Young (view profile)

Functions to compute log(sin(Z)) and log(cos(Z)) avoiding overflow for large abs(imag(Z)). (mathematics, complex numbers, log)

logcos(z)

logsin(z)

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updated 4 years ago

2-D convolution using the FFT by David Young

David Young (view profile)

Convolution in 2-D using the Fast Fourier Transform. (convolution, filtering, fft)

conv_fft2(x, m, shape)

exindex(arr, varargin)

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updated almost 5 years ago

Fourier transform demonstration by David Young

David Young (view profile)

An introductory demonstration of the discrete Fourier transform, making use of the fft function. (fourier transform, discrete fourier tran..., fast fourier transfor...)

Introductory Fourier Transform Demonstration

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updated 5 years ago

Extended array indexing by David Young

David Young (view profile)

Indexes a virtual array formed by extending an array indefinitely on each dimension. (subscript, index, array)

exindex(arr, varargin)

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updated 5 years ago

Log-polar image sampling by David Young

David Young (view profile)

Resamples an image from a conventional grid to a log-polar grid, and back. (image analysis, image transform, image resampling)

logsampback(logarr, rmin, rmax)

logsample(arr, rmin, rmax, xc, yc, nr, nw)

logtform(rmin, rmax, nr, nw)

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updated 5 years ago

Elementary Cellular Automata by David Young

David Young (view profile)

Simulates any 1D nearest-neighbour binary cellular automaton. (cellular automata, cellular automaton)

elementaryCellularAutomata(rule, n, width, randfrac)

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updated 6 years ago

Gabor function masks by David Young

David Young (view profile)

Create Gabor-function convolution masks (convolution, filtering, image processing)

gabormask(Size, sigma, period, orient)

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