16-bit image files creating reading 1-bit image files 24-bit image files 4-bit image files 8-bit image files creating reading adapthisteq increasing contrast using adaptive filters two-dimensional adaptive noise filtering Adjust Contrast tool autoscaling creating overview using using the dropper button affine transformations definition using imtransform aliasing definition alpha channel analyzing images edge detection intensity profiles pixel values quadtree decomposition antialiasing applycform applylut example modifying text in an image approximation in indexed images of an image background of colors area of binary images of image regions arrays storing images autoscaling image contrast averaging filter creating example axes2pix background of an grayscale image basicimageinfo bestblk bicubic interpolation bilinear interpolation binary images applying a lookup table calculating the Euler number changing the display colors of constructing lookup tables displaying feature measurement finding area flood fill operation image area labeling connected components labeling connected components labeling lookup table operations morphological operations object selection perimeter determination selecting objects in using neighborhood operations binary masks creating bit depth 1-bit images screen bit depth blind deconvolution algorithm used for deblurring blkproc specifying overlap using block processing block size column processing distinct blocks padding borders in block processing sliding neighborhoods using nlfilter border padding in block processing border replication in image processing borders controlling in figure window boundary padding See border padding boundary ringing in image deblurring boundary tracing bounding box finding for a region brightness adjusting interactively adjusting the window/level brightness adjustment bwarea bwarea using bwareaopen bwboundaries bwdist using bweuler bwhitmiss bwlabel bwlabeln bwmorph skeletonization example bwpack bwperim bwselect bwtraceboundary using bwulterode bwunpack camera read-out noise Canny edge detector using the edge function center of mass calculating for region center pixel calculating checkerboard Choose Colormap tool using chrominance in CIE color spaces in NTSC color space in YCbCr color space CIE color spaces CIELAB color space closing morphology cmpermute cmunique col2im colfilt compared to nlfilter example using color approximation dithering quantization quantization performed by rgb2ind reducing number of colors color approximation performed by rgb2ind color cube a description of quantization of color planes of an HSV image of an RGB image slice of color cube color reduction color spaces converting among converting between converting between data encodings device-independent color spaces HSV NTSC NTSC NTSC YCbCr YIQ colorbar using colorbars adding colorcube colormap mapping colormaps brightening choosing in Image Tool creating a colormap using colorcube darkening rearranging colors in removing duplicate entries in column processing in neighborhood operations reshaping columns into blocks composite transformations conformal transformations conndef connected components labeling using bwlabel connectivity overview specifying custom constant component See zero-frequency component contour plots text labels contrast adjusting interactively adjusting the window/level contrast adjustment decreasing contrast increasing contrast specifying limits automatically contrast stretching understanding with decorrelation stretching See also contrast adjustment contrast-limited adaptive histogram equalization (CLAHE) Control Point Selection Tool appearance of control point symbols changing view of images saving a session saving control points specifying control points starting using using point prediction control points appearance of prediction saving selecting specifying conv2 compared to imfilter conversions between image types convmtx2 convn compared to imfilter convolution convolution matrix definition Fourier transform and two-dimensional with imfilter convolution kernel definition coordinate systems pixel coordinates spatial coordinates corr2 calculating summary statistics correlation definition Fourier transform with imfilter correlation coefficient correlation kernel definition cp2tform using cpcorr example cpselect using cpstruct2pairs cropping an image cross-correlation improving control point selection damping for noise reduction data types converting between double-precision (double) in image filtering DC component See zero-frequency component See zero-frequency component dct2 equations dctmtx using deblurring avoiding boundary ringing conceptual model overview overview of functions use of frequency domain using the blind deconvolution algorithm using the Lucy-Richardson algorithm with regularized filter with the Wiener filter decomposition of structuring elements example getting sequence deconvblind example deconvlucy example deconvreg example deconvwnr example decorrelation stretching See also contrast adjustment decorrstretch detail rectangle getting position of in Control Point Selection Tool specifying color in Image Tool DICOM files reading and writing DICOM unique identifier generating dicomanon dicomdict dicominfo dicomread dicomuid dicomwrite Digital Imaging and Communications in Medicine See DICOM files dilation grayscale discrete cosine transform image compression transform matrix transform matrix discrete Fourier transform disk filter display depth See screen color resolution display range getting information about Display Range tool creating in Image Tool overview display techniques displaying images at true size multiple images displaying images adding a colorbar binary binary images with different colors comparison of functions controlling figure window grayscale images indexed images initial size multiple images multiple images in figure special techniques texture mapping toolbox preferences for truecolor unconventional ranges of data using imshow using the Image Tool distance between pixels Euclidean distance transform distinct block operations overlap zero padding distortion operator dither dithering example edge example edge detection Canny method example methods Sobel method edgetaper avoiding boundary ringing enhancing images decorrelation stretching intensity adjustment noise removal entropy entropyfilt erosion grayscale Euclidean distance Euclidean distance Euler number calculating exploring images using Image Tool exporting data in Image Tool fan2para fanbeam using fan-beam projection data arc geometry computing line geometry reconstructing image from fast Fourier transform zero padding See also Fourier transform feature measurement area binary images bounding box center of mass fft fft2 example using fftn fftshift example using figure controlling borders files displaying images from disk filling a region filling holes in images filter design frequency sampling method frequency sampling method frequency transformation method frequency transformation method windowing method windowing method windowing method filter2 compared to imfilter example filtering a region masked filtering filters adaptive adaptive averaging binary masks computing frequency response designing disk finite impulse response (FIR) frequency response Gaussian imfilter Infinite Impulse Response (IIR) Laplacian linear Log median median motion multidimensional order-statistic Prewitt Sobel unsharp unsharp masking findbounds FIR filters transforming from one-dimensional to two-dimensional flat-field correction fliptform flood-fill operation Fourier transform applications of the Fourier transform centering the zero-frequency coefficient computing frequency response convolution and correlation DFT coefficients examples of transform on simple shapes fast convolution with for performing correlation frequency domain increasing resolution padding before computation two-dimensional zero-frequency component freqspace example frequency domain frequency response computing computing desired response matrix of linear filters frequency sampling method (filter design) using fsamp2 frequency transformation method (filter design) using ftrans2 freqz example freqz2 computing frequency response of linear filters example fsamp2 example fspecial creating predefined filters ftrans2 example fwind1 example fwind2 example gamma correction Gaussian convolution kernel frequency response of Gaussian filter Gaussian noise adding geocoded images geometric operations cropping interpolation resizing georegistered images getheight getimage example using with Image Tool getimagemodel getline getneighbors getnhood getpts getrangefromclass getrect getsequence graphical user interfaces (GUIs) building graphics card graphics file formats converting from one format to another writing data gray2ind grayscale images displaying flood-fill operation grayscale morphological operations grayslice graythresh thresholding image values histeq example increase contrast example histogram equalization histogram equalization histograms holes filling tracing boundaries hough using houghlines using houghpeaks using HSV color space color planes of hsv2rgb hue in HSV color space in NTSC color space ICC profiles processing iccread iccwrite idct2 ifanbeam using ifft ifft2 ifftn IIR filters im2bw im2col im2double example im2int16 im2int16 im2java2d im2single im2uint16 im2uint8 imabsdiff imadd imadjust brightening example example gamma correction and gamma correction example increase contrast example setting limits automatically image analysis contour plots edge detection histograms intensity profiles overview pixel values quadtree decomposition summary statistics image area (binary images) image arithmetic combining functions overview truncation rules image display special techniques image editing image filtering data types unsharp masking with imfilter Image Information tool creating using image metadata viewing image properties set by imshow image registration fine-tuning point placement overview procedure selecting control points specifying control point pairs types of transformations using control point prediction image rotation specifying interpolation method specifying size of output image Image Tool choosing a colormap closing compared to imshow controlling initial magnification exploring images exporting data importing data opening overview panning images printing specifying image magnification using the Pixel Region tool zoom tools image transformations affine custom local weighted mean piecewise linear polynomial projective supported by cp2tform types of using imtransform image types binary converting grayscale indexed interpolation and multiframe images supported by the toolbox truecolor See also indexed images, grayscale images, binary images, truecolor images, multiframe imageinfo imagemodel images adjusting contrast analyzing arithmetic operations brightness control causes of blurring creating movies data types displaying multiple images displaying multiple images displaying multiple images in figure feature measurement filling holes in finding image minima and maxima getting data from axes getting information about getting information about display range how MATLAB stores image types improving contrast printing reducing number of colors registering restoring blurred images returning information about statistical analysis of using imshow viewing as a surface plot viewing metadata imapprox example imbothat imclearborder imclose using imcomplement imcontour example imcontrast imcrop example imdilate imdisplayrange imdivide imerode closure example imextendedmax example imextendedmin imfill example imfilter compared to other filtering functions convolution option correlation option padding options using imfinfo example imgca imgcf imgetfile imhandles imhist creating a histogram imhmax imhmin imimposemin imlincomb example immagbox immovie example immultiply imnoise example salt & pepper example imopen using imoverview imoverviewpanel impixel example impixelinfo impixelinfoval impixelregion impixelregionpanel importing data in Image Tool impositionrect improfile example grayscale example imread example for multiframe image imreconstruct example imregionalmax imregionalmin imresize using imrotate specifying interpolation method specifying size of output image using imscrollpanel imshow compared to Image Tool displaying images displaying unconventional range data example for binary images example for grayscale images example for truecolor images used with indexed images imsubtract imtool compared to imshow displaying unconventional range data example for binary images example for grayscale images example for truecolor images overview used with indexed images imtophat imtransform using imview imwrite example ind2gray ind2rgb indexed images converting from intensity converting from RGB displaying reducing number of colors in infinite impulse response (IIR) filter Intel Performance Primitives Library intensity adjustment gamma correction histogram equalization specifying limits automatically See also contrast adjustment intensity images converting from matrices converting from RGB converting to indexed Seegrayscale images intensity profiles intensity profiles interpolation bicubic bilinear intensity profiles nearest-neighbor tradeoffs between methods within a region of interest intlut inverse Radon transform example filtered backprojection algorithm ippl iptaddcallback iptcheckconn iptcheckhandle iptcheckinput iptcheckmap iptchecknargin iptcheckstrs iptcondir iptdemos iptgetapi iptgetpref using iptnum2ordinal iptremovecallback iptsetpref using iptwindowalign iradon iradon example isbw isflat isgray isicc isind isrgb JPEG compression discrete cosine transform and lab2double lab2uint16 lab2uint8 label matrix creating viewing as pseudocolor image label2rgb labeling connected components levels of contours Laplacian filter Laplacian of Gaussian edge detector line detection line segment pixel values along linear conformal transformations linear filtering linear filtering convolution filter design FIR filters IIR filters noise removal and local weighted mean transformations Log filters lookup tables constructing using Lucy-Richardson algorithm used for deblurring luminance in NTSC color space in YCbCr color space magnification specifying in Image Tool specifying initial value in Image Tool Magnification box creating magnifying See resizing images makecform makelut example makeresampler maketform marker image creating definition mask image definition masked filtering mat2gray matrices converting to intensity images storing images in maxima finding in images imposing suppressing McClellan transform mean2 mean2 medfilt2 example using median filtering median filtering metadata viewing minima finding in images imposing suppressing minimum variance quantization modular tools connecting creating your own embedding in existing figures navigation aids overview positioning in a GUI specifying parent of using utility functions moiré patterns montage example morphological operations closing diagonal fill dilation erosion grayscale opening overview predefined operations shrinking objects skeletonization morphological reconstruction finding peaks and valleys overview morphology See also morphological reconstruction motion filters movies creating from images creating from images playing multidimensional filters multiframe images about displaying limitations multilevel thresholding navigational aids creating nearest-neighbor interpolation neighborhoods binary image operations neighborhood operations nlfilter nlfilter example noise adding to an image noise amplification reducing noise removal adaptive filtering (Weiner) and Gaussian noise grain noise linear filtering and median filter and salt and pepper noise nonimage data displaying as image nonlinear filtering normalized cross-correlation normxcorr2 NTSC color space NTSC color space NTSC color space ntsc2rgb ntsc2rgb object selection objects tracing boundaries observed image in image registration opening morphology optical transfer function (OTF) order-statistic filtering ordfilt2 orthonormal matrix orthophoto defined orthorectified image otf2psf use of overlap in distinct block operations Overview tool creating customizing getting position of detail rectangle printing image in starting in Image Tool using padarray padding borders in block processing options with imfilter panning images using the Image Tool para2fan parallel beam projections perimeter determination in binary images phantom phantom piecewise linear transformations Pixel Information tool creating overview Pixel Region tool creating customizing determining location of cursor overview printing contents selecting a region using using in Image Tool pixel regions viewing pixel values along a line segment returning using a mouse using impixel using pixval using the Pixel Region tool pixels correcting for bad pixels defining connectivity definition displaying coordinates of Euclidean distance between getting pixel value information in Image Tool getting value of using Pixel Information tool returning coordinates of selecting viewing values of pixel regions pixval using PNG (Portable Network Graphics) files writing as 16-bit point mapping for image registration point spread function (PSF) importance of in deblurring Poisson noise adding poly2mask polygon pixels inside selecting a polygonal region of interest polynomial transformations predicting control point locations in image registration preferences getting value of Image Processing Toolbox display preferences ImshowAxesVisible ImshowBorder ImshowInitialMagnification ImtoolInitialMagnification setting value of Prewitt edge detector Prewitt filters printing contents of Overview tool contents of Pixel Region tool printing images from Image Tool profiles reading ICC color profiles projections parallel beam projective transformations projective transformations psf2otf use of qtdecomp example qtgetblk qtsetblk quadtree decomposition quadtree decomposition getting block values setting block values quantization minimum variance performed by rgb2ind tradeoffs between using minimum variance and uniform quantization methods radon example Radon transform center pixel description of example inverse Radon transform line detection example of the Shepp-Logan Head phantom relationship to Hough transform rangefilt rank filtering See also order-statistic filtering read-out noise correcting real orthonormal matrix reconstruction morphological reference image in image registration reflect region labeling region of interest based on color or intensity binary masks filling filtering polygonal selecting using arbitrary binary masks region property measurement regional maxima definition imposing suppressing regional minima definition imposing suppressing regionprops using using registering an image regularized filter used for deblurring replication to avoid border effect resizing images antialiasing resolution screen color resolution See also bit depth RGB color cube description of quantization of RGB images converting to indexed converting to intensity Seetruecolor images rgb2gray rgb2hsv converting RGB to HSV color space example rgb2ind colormap mapping example example in minimum variance quantization minimum variance quantization example specifying a colormap to use uniform quantization example used in dithering rgb2ntsc example rgb2ycbcr example Richardson-Lucy algorithm See Lucy-Richardson ringing in image deblurring Roberts edge detector roicolor roicolor roifill example roifilt2 contrast example inline example roipoly example rotation of images salt and pepper noise adding sampling handling undersampled images saturation in HSV color space in NTSC color space screen bit depth screen color resolution ScreenDepth Scroll Panel tool creating scroll panels understanding Shepp-Logan head phantom shrinking See resizing images Signal Processing Toolbox hamming function skeletonization sliding neighborhood operations center pixel in padding in Sobel edge detector Sobel filters spatial coordinates speckle noise adding statistical properties mean of image objects standard deviation std2 std2 stdfilt storage classes converting between strel stretchlim adjusting image contrast using using Adjust Contrast tool structuring elements creating decomposition of decomposition sequence determining composition subimage subtraction of one image from another surf viewing images target images definiition displaying getting handle to specifying template matching texture mapping tformarray tformfwd tforminv thresholding to create a binary image to create indexed image from intensity image tomography tools creating your own modular tracing boundaries transformation matrix transforms discrete cosine discrete cosine discrete Fourier transform Fourier inverse Radon Radon two-dimensional Fourier transform translate transparency truecolor images displaying measuring the intensities of each color plane reducing number of colors truesize truncation rules for image arithmetic operators uint16 storing images in uint8 storing images in uintlut undersampling correcting uniform quantization See quantization unsharp filters unsharp masking warp example watershed weight array in deblurring whitepoint Wiener filter deblurring with wiener2 adaptive filtering using window/level adjusting windowing method (filter design) windowing method (filter design) windowing method (filter design) X-ray absorption tomography XYZ color space xyz2double xyz2uint16 YCbCr color space ycbcr2rgb using YIQ color space zero padding and the fast Fourier transform image boundaries zero-cross edge detector zero-frequency component zooming Control Point Selection Tool in Image Tool