Contrast Enhancement and Filtering


ADAPT_HIST_EQUAL: Perform adaptive histogram equalization

BANDPASS_FILTER: Apply a bandpass filter to a one-channel image.

BANDREJECT_FILTER: Apply a band reject filter on a one-channel image.

BUTTERWORTH: Return the absolute value of the low-pass Butterworth kernel.

BYTSCL: Scale all values of an array into range of bytes.

CANNY: Perform the Canny edge-detection algorithm.

CONVOL: Convolve two vectors or arrays.

DIGITAL_FILTER: Calculate coefficients of a non-recursive, digital filter.

ESTIMATOR_FILTER: Apply an order statistic noise-reduction filter to an image.

FFT: Return the Fast Fourier Transform of an array.

GABOR_FILTER: Apply a Gabor filter to a two-dimensional array.

HILBERT: Construct a Hilbert transform.

HIST_EQUAL: Histogram-equalize an image.

IR_FILTER: Perform the infinite or finite impulse response filter on data.

LEAST_SQUARES_FILTER: Reduces degradation and noise in an image.

LEEFILT: Perform the Lee filter algorithm on an image array.

MEAN_FILTER: Apply mean filter noise reduction on a one- or multi-channel image.

MEDIAN: Return the median value of Array or applies a median filter.

ROBERTS: Return an approximation of Roberts edge enhancement.

SMOOTH: Smooth with a boxcar average.

SOBEL: Return an approximation of Sobel edge enhancement.

UNSHARP_MASK: Perform an unsharp-mask sharpening filter.

WIENER_FILTER: Reduce degradation and noise in an image.

Feature Extraction/Image Segmentation


DEFROI: Defines an irregular region of interest of an image. (Direct Graphics)

GABOR_FILTER: Apply a Gabor filter to a two-dimensional array.

HISTOGRAM: Computes the density function of an array.

HOUGH: Return the Hough transform of an image.

IMAGE_STATISTICS: Compute sample statistics for a given array of values.

IMAGE_THRESHOLD: Generate a threshold value for an image.

ISOCONTOUR: Perform a contouring algorithm.

ISOSURFACE: Return topologically consistent triangles by using oriented tetrahedral decomposition.

LABEL_REGION: Label regions (blobs) of a bi-level image.

MEDIAN: Return the median value of Array or applies a median filter.

PROFILES Procedure: Interactively examines image profiles.

RADON: Return the Radon transform of an image.

REGION_GROW: Perform region growing.

SEARCH2D: Finds objects or regions of similar data within a 2D array.

THIN: Return the skeleton of a bi-level image.

UNIQ: Return subscripts of the unique elements in an array.

WATERSHED: Apply the morphological watershed operator to a grayscale image.

WHERE: Return subscripts of nonzero array elements.

Image Display


DISSOLVE: Provides a digital “dissolve” effect for images.

IDLgrImage: Create an image object.

IDLgrPalette: An object that contains a red-green-blue color lookup table.

SMOOTH: Creates a scrolling graphics window for examining large images.

TV: Displays an image. To scale and display the image, use TVSCL. (Direct Graphics)

TVCRS: Manipulates the image display cursor. (Direct Graphics)

TVLCT: Loads display color tables. (Direct Graphics)

TVSCL: Scales and displays an image. (Direct Graphics)

ZOOM: Zooms portions of the display. (Direct Graphics)

ZOOM_24: Zooms portions of true-color (24-bit) display. (Direct Graphics)

Image Geometry Transformations


CONGRID: Resamples an image to any dimensions.

EXPAND: Shrinks/expands image using bilinear interpolation.

EXTRAC: Return sub-matrix of input array. Array operators (e.g., * and :) should usually be used instead.

INTERPOLATE: Return an array of interpolates.

INVERT: Computes the inverse of a square array.

POLY_2D: Perform polynomial warping of images.

POLYWARP: Perform polynomial spatial warping.

REBIN: Resizes a vector or array by integer multiples.

REFORM: Changes array dimensions without changing the total number of elements.

REVERSE: Reverses the order of one dimension of an array.

ROT: Rotates an image by any amount.

ROTATE: Rotates/transposes an array in multiples of 90 degrees.

SHIFT: Shifts elements of vectors or arrays by a specified number of elements.

TRANSPOSE: Transposes an array.

WARP_TRI: Warps an image using control points.

Morphological Image Operators


DILATE: Implements morphologic dilation operator on binary and grayscale images.

ERODE: Implements the erosion operator on binary and grayscale images and vectors.

LABEL_REGION: Labels regions (blobs) of a bi-level image.

MORPH_CLOSE: Apply closing operator to binary or grayscale image.

MORPH_DISTANCE: Estimates N-dimensional distance maps, which contain for each foreground pixel the distance to the nearest background pixel, using a given norm.

MORPH_GRADIENT: Apply the morphological gradient operator to a grayscale image.

MORPH_HITORMISS: Apply the hit-or-miss operator to a binary image.

MORPH_OPEN: Apply the opening operator to a binary or grayscale image.

MORPH_THIN: Perform a thinning operation on binary images.

MORPH_TOPHAT: Apply top-hat operator to a grayscale image.

WATERSHED: Apply the morphological watershed operator to a grayscale image.

Regions of Interest


CW_DEFROI: Creates compound widget used to define region of interest. (Direct Graphics)

DEFROI: Defines an irregular region of interest of an image. (Direct Graphics)

DRAW_ROI: Draws region or group of regions to current Direct Graphics device. (Direct Graphics)

IDLanROI: Represents a region of interest used for analysis.

IDLanROIGroup: Analytical representation of a group of regions of interest.

IDLgrROI: Object graphics representation of a region of interest.

IDLgrROIGroup: Object Graphics representation of a group of regions of interest.

LABEL_REGION: Labels regions (blobs) of a bi-level image.

REGION_GROW: Grows an initial region to include all areas that match specified constraints.

XROI: Utility for defining regions of interest, and obtaining geometry and statistical data about these ROIs.