image
The Octave-forge Image package provides functions for processing images. The package also provides functions for feature extraction, image statistics, spatial and geometric transformations, morphological operations, linear filtering, and much more.
Select category:
Analysis and Statistics
Arithmetics
Black and white image functions
Colour maps and Colour controls
Display
Enhancement and Restoration
Filtering and Transforms
Morhophological Operations
Read/write
Region-based and block processing
Spatial transformations
Types and Type conversions
Utilities
Image Registration
Compute correlation coefficients of images.
Find edges using various methods.
Convolve 2 dimensional signals using the FFT.
Convolve N dimensional signals using the FFT for computation.
Compute mean value of array.
Returns the standard deviation for a 2D real type matrix.
Computes the entropy of an image.
Computes the local entropy in a neighbourhood around each pixel in an image.
Performs quadtree decomposition.
Obtain block values from a quadtree decomposition.
Set block values in a quadtree decomposition.
Compute the gray-level co-occurrence matrix (GLCM) for an image.
Calculates the gray-level co-occurrence matrix P of a gray-level image IM.
Compute the Hough transform to find lines in a binary image.
Extract line segments from a Hough transform.
Find peaks in a Hough transform.
Perform the Hough transform for lines or circles.
Calculate the straight line Hough transform of a binary image I.
Perform the Hough transform for circles with radius R on the black-and-white image BW.
Performs edge-preserving bilateral filtering on an image.
Produces box filtering of an image, quicker than imfilter.
Find circles in image using the circular Hough transform.
Filters an image with a 2D gaussian kernel and returns a smoothed image.
Compute the gradient magnitude and direction in degrees for an image.
Compute the x and y gradients of an image using various methods.
Produce histogram counts of an image.
Find local spatial maximas.
Compute mean squared error.
Compute normalized cross-correlation.
Compute global image threshold for histogram using Otsu's method.
Compute peak signal-to-noise ratio.
Computes the local intensity range in a neighbourhood around each pixel in an image.
Compute properties of image regions.
Computes the local standard deviation in a neighbourhood around each pixel in an image.
Return absolute difference of two images or a constant to an image.
Add two images or a constant to an image.
Linear combination of color channels.
Compute image complement or negative.
Divide image by another image or constant.
Combine images linearly.
Multiply image by another image or a constant.
Subtract two images or a constant to an image.
Uses lookup tables to perform a neighbour operation on binary images.
Estimate total area of objects on a binary image.
Filter objects from image based on their sizes.
Trace the boundaries of the objects in a binary image.
Find connected objects.
Compute distance transform in binary image.
Calculate the Euler number of a binary image.
Perform a flood-fill operation on the binary image.
Perform binary hit-or-miss transform.
Label binary 2 dimensional image.
Label foreground objects in the n-dimensional binary image.
Perform morphological operation on binary image.
Pack binary image.
Find perimeter of objects in binary images.
Filter objects from image based on their properties.
Select connected regions in a binary image.
Unpack binary image.
Determine the Freeman chain code for a boundary.
Create labelled matrix from bwconncomp structure.
Create a lookup table which can be used by applylut.
Compute angle between RGB colors in degrees.
Define a colour map which smoothly traverses the given colors.
Convert RGB values to YCbCr.
Convert wavelength in nm into an RGB value set.
Convert YCbCr color space to RGB.
Convert axes coordinates to pixel coordinates.
Create montage from multiple images.
Display images in subplots.
Draw circles on figure.
Equalize histogram of grayscale image.
Adjust image or colormap intensity (values).
Add noise to image.
Smooth the given image using several different algorithms.
Two dimensional median filtering.
Two dimensional ordered filtering.
N dimensional ordered filtering.
Find limits to contrast stretch an image.
Apply Wiener deconvolution filter.
Estimate bounds for spatial transformation.
Create spatial filters for image processing.
Apply a linear filter on a given image.
Sharpen image using unsharp masking.
Transform image.
Calculate the integral image.
Calculate the 3D integral image.
Convert integer values with lookup table (LUT).
Performs filtered back-projection on projections to reconstruct an approximation of the original image.
Performs non-maximum suppression on the given edge data.
Calculates the 2D-Radon transform of the input matrix I at given angles.
Performs rho filtering on the parallel ray projections provided.
Apply an adaptive noise reduction filter.
Perform area opening.
Create connectivity array.
Perform morphological bottom hat filtering.
Clear borders of objects or ligher structures.
Perform morphological closing.
Perform morphological dilation.
Perform morphological erosion.
Caculate the (morphological) extended maxima of a given image.
Caculate the (morphological) extended minima of a given image.
Fill image holes or regions.
Caculate the morphological h-maximum transform of an image IM.
Caculate the morphological h-minimum transform of an image IM.
Modify the input image to only have regional minima at the marker positions given by the nonzero pixels of given matrix.
Perform morphological opening.
Perform the morpological reconstruction of a given image.
Compute regional maxima.
Compute regional minima.
Perform morphological top hat filtering.
Perform morphological gradient.
Return the heights of a non-flat structuring element.
Get neighbors relative position and height.
Return the neighborhood of a given structuring element.
Decompose structuring element.
Say if a structuring element object is flat or not.
Reflect structuring element of strel object.
Create a strel (structuring element) object for morphology operations.
Generate a new structuring element, which is SE translated in rows and columns as expressed in the offset 2-dimensional array V.
Compute watershed transform.
Read header of an Analyze 7.5 file.
Read image data of an Analyze 7.5 file.
Write image data to an Analyze 7.5 file.
Read value of TAGs from TIFF files.
Calculate block best size for block processing.
Processes image in blocks using user-supplied function.
Rearrange block columns back into matrix.
Apply function to matrix blocks
Rearrange blocks from matrix into columns.
Get pixel values.
Process matrix in sliding blocks with user-supplied function.
Convert a polygon to a region mask.
Select a Region Of Interest of an image based on color.
tform is a representation of an affine 2D transform.
tform is a representation of an affine 3D transform.
Return a transformation structure T (see "help maketform" for the form of the structure) that can be further used to transform coordinates between an input space and an ouput space.
Crop image.
Applies the spatial perspective homogeneous transformation to a given image.
Compute gaussian pyramid expansion or reduction.
Applies any geometric transformation to a given image.
Resize image with interpolation
Rotate image about its center.
Applies a shear to a given image.
Translate a 2D image by (x,y) using Fourier interpolation.
Create a transform structure to be used for spatial transformations between an input space and an output space.
Arbitrary rotation and scaling of a gray-scale image using fast bilinear interpolation.
Given a transform structure T, transform coordinates UV in the input space into coordinates XY in the output space.
Given a transform structure T, transform coordinates XY in the output space into coordinates UV in the input space.
Compute local threshold value for each pixel using local mean intensity in the neighborhood of each pixel.
Create indexed image from intensity image using multilevel thresholding.
Compute global image threshold.
Convert image to binary, black and white, by threshold.
Convert image to int16.
Convert image to single precision.
Convert image to uint16.
Convert image to uint8.
Convert an image to a binary image using a specified thresholding method.
Convert image to specific data type.
Quantize image with multiple threshold levels and values.
Return true if a given image is a black and white image.
Return true if a given image is a grayscale image.
Return true if a given image is an indexed image.
Return true if a given image is a RGB image.
Convert L*a*b* data to double precision.
Transform a colormap or image from CIE L*a*b* to sRGB color space.
Convert L*a*b* data to single precision.
Convert L*a*b* data to uint16 precision.
Convert L*a*b* data to uint8 precision.
Transform a colormap or image from CIE L*a*b* to CIE XYZ color space.
Convert labeled image into RGB.
Convert a matrix to an intensity image.
Transform a colormap or image from luminance-chrominance (NTSC) space to red-green-blue (RGB) color space.
Transform a colormap or image from sRGB to CIE L*a*b* color space.
Transform a colormap or image from red-green-blue (RGB) color space to luminance-chrominance (NTSC) space.
Transform a colormap or image from sRGB to CIE XYZ color space.
Transform a colormap or image from CIE XYZ to CIE L*a*b* color space.
Transform a colormap or image from CIE XYZ to sRGB color space.
Create checkerboard.
Blur border (edges) of image to prevent ringing artifacts.
Return display range of image.
Get information about image attributes.
Composite of two images.
Open GUI dialogue to select image files.
Combines two images using a specified method.
Insert text in image.
Check if argument is valid connectivity.
Check if argument is valid colormap.
Convert number to ordinal string.
Compute PSF from OTF.
Pad array or matrix.
Create computational phantom head.
Compute OTF from PSF.
Determine if image contains points in world coordinate system.
Display the properties of imref2d object
Reference 2D image to world coordinates.
Convert from intrinsic to world coordinates.
Determine if object and image are size-compatible.
Implementation of subasgn method to imref2d object
Implementation of subref method to imref2d object
Convert from world to intrinsic coordinates.
Convert world coordinates to row and column subscripts.
Determine if image contains points in world coordinate system.
Display the properties of imref3d object
Reference 3D image to world coordinates.
Convert from intrinsic to world coordinates.
Implementation of subsasgn method to imref3d object
Implementation of subref method to imref3d object
Convert from world to intrinsic coordinates.
Convert world coordinates to row, column and plane subscripts.
Package: image