Getting Started

    Preface
        What Is the Image Processing Toolbox?
        Related Products
        Configuration Notes
        About the Documentation
            Structure of the Documentation
            Image Credits
            Terminology
            MATLAB Newsgroup

        Typographical Conventions
        Image Processing Demos

    Getting Started
        Example 1 -- Some Basic Topics
            1. Read and Display an Image
            2. Check How the Image Appears in the Workspace
            3. Perform Histogram Equalization on the Image
            4. Write the Image to a Disk File
            5. Check the Contents of the Newly Written File

        Example 2 -- Advanced Topics
            1. Read and Display an Image
            2. Estimate the Value of Background Pixels
            3. View the Background Approximation as a Surface
            4. Create an Image with a Uniform Background
            5. Adjust the Contrast in the Processed Image
            6. Create a Binary Version of the Image
            7. Determine the Number of Objects in the Image
            8. Examine the Label Matrix
            9. Display the Label Matrix as a Pseudocolor Indexed Image
            10. Measure Object Properties in the Image
            11. Compute Statistical Properties of Objects in the Image

        Where to Go from Here
            Online Help
            Toolbox Demos

Examples

Introduction

    Terminology
    Images in MATLAB and the Image Processing Toolbox
        Working with Images in MATLAB
        Storage Classes in the Toolbox

    Image Types in the Toolbox
        Indexed Images
        Intensity Images
        Binary Images
        RGB Images
        Multiframe Image Arrays
        Summary of Image Types and Numeric Classes
        Converting Image Types

    Reading and Writing Image Data
        Reading a Graphics Image
        Writing a Graphics Image
        Querying a Graphics File
        Converting Image Storage Classes
        Converting Graphics File Formats
        Reading and Writing DICOM Files

    Image Arithmetic
        Summary of Image Arithmetic Functions
        Image Arithmetic Truncation Rules
        Adding Images
        Subtracting Images
        Multiplying Images
        Dividing Images
        Nesting Calls to Image Arithmetic Functions

    Coordinate Systems
        Pixel Coordinates
        Spatial Coordinates

Displaying and Printing Images

    Terminology
    Overview
    Using the Image Viewer to Display Images
        Opening and Closing the Image Viewer
        Understanding Image Viewer Tools
        Using Image Viewer Navigation Aids
        Using the Pixel Region Tool
        Using the Image Information Tool
        Managing Image Viewer Memory Usage

    Using imshow to Display Images
        Opening Images
        Specifying the Initial Image Size
        Viewing Multiple Images
        Understanding Handle Graphics Object Property Settings

    Displaying Different Image Types
        Displaying Indexed Images
        Displaying Intensity Images
        Displaying Binary Images
        Displaying RGB Images

    Special Display Techniques
        Adding a Colorbar
        Displaying All Frames of a Multiframe Image at Once
        Converting a Multiframe Image to a Movie
        Texture Mapping

    Printing Images
    Setting Toolbox Display Preferences
        Toolbox Preferences
        Retrieving the Value of Toolbox Preferences
        Setting the Value of Toolbox Preferences

Spatial Transformations

    Terminology
    Interpolation
        Image Types

    Image Resizing
        Specifying the Size of the Output Image
        Specifying the Interpolation Method
        Using Filters to Prevent Aliasing

    Image Rotation
        Specifying the Interpolation Method
        Specifying the Size of the Output Image

    Image Cropping
    Performing General Spatial Transformations
        Specifying the Transformation Type
        Performing the Transformation
        Advanced Spatial Transformation Techniques

Image Registration

    Terminology
    Registering an Image
        Point Mapping
        Example: Registering to a Digital Orthophoto

    Types of Supported Transformations
    Selecting Control Points
        Using the Control Point Selection Tool
        Starting the Control Point Selection Tool
        Viewing the Images
        Specifying Matching Control Point Pairs
        Saving Control Points

    Using Correlation to Improve Control Points

Neighborhood and Block Operations

    Terminology
    Block Processing Operations
        Types of Block Processing Operations

    Sliding Neighborhood Operations
        Padding Borders
        Linear and Nonlinear Filtering

    Distinct Block Operations
        Overlap

    Column Processing
        Sliding Neighborhoods
        Distinct Blocks

Linear Filtering and Filter Design

    Terminology
    Linear Filtering
        Convolution
        Correlation
        Filtering Using imfilter
        Using Predefined Filter Types

    Filter Design
        FIR Filters
        Frequency Transformation Method
        Frequency Sampling Method
        Windowing Method
        Creating the Desired Frequency Response Matrix
        Computing the Frequency Response of a Filter

Transforms

    Terminology
    Fourier Transform
        Definition of Fourier Transform
        Discrete Fourier Transform
        Applications of the Fourier Transform

    Discrete Cosine Transform
        The DCT Transform Matrix
        DCT and Image Compression

    Radon Transform
        Using the Radon Transform to Detect Lines
        Inverse Radon Transform
        Example: Reconstructing an Image from Parallel Projection Data

    Fan-Beam Projection Data
        Computing Fan-Beam Projection Data
        Reconstructing an Image from Fan-Beam Projection Data
        Working with Fan-Beam Projection Data

Morphological Operations

    Terminology
    Dilation and Erosion
        Understanding Dilation and Erosion
        Structuring Elements
        Dilating an Image
        Eroding an Image
        Combining Dilation and Erosion
        Dilation- and Erosion-Based Functions

    Morphological Reconstruction
        Marker and Mask
        Pixel Connectivity
        Flood-Fill Operations
        Finding Peaks and Valleys

    Distance Transform
    Objects, Regions, and Feature Measurement
        Connected-Component Labeling
        Selecting Objects in a Binary Image
        Finding the Area of the Foreground of a Binary Image
        Finding the Euler Number of a Binary Image

    Lookup Table Operations

Analyzing and Enhancing Images

    Terminology
    Pixel Values and Statistics
        Pixel Selection
        Intensity Profile
        Image Contours
        Image Histogram
        Summary Statistics
        Region Property Measurement

    Image Analysis
        Edge Detection
        Boundary Tracing
        Quadtree Decomposition

    Intensity Adjustment
        Adjusting Intensity Values to a Specified Range
        Histogram Equalization
        Contrast-Limited Adaptive Histogram Equalization
        Decorrelation Stretching

    Noise Removal
        Linear Filtering
        Median Filtering
        Adaptive Filtering

Region-Based Processing

    Terminology
    Specifying a Region of Interest
        Selecting a Polygon
        Other Selection Methods

    Filtering a Region
        Example: Filtering a Region in an Image
        Specifying the Filtering Operation

    Filling a Region

Image Deblurring

    Terminology
    Understanding Deblurring
        Causes of Blurring
        Deblurring Model

    Using the Deblurring Functions
        Deblurring with the Wiener Filter
        Deblurring with a Regularized Filter
        Deblurring with the Lucy-Richardson Algorithm
        Deblurring with the Blind Deconvolution Algorithm
        Creating Your Own Deblurring Functions

    Avoiding Ringing in Deblurred Images

Color

    Terminology
    Working with Different Screen Bit Depths
        Determining Screen Bit Depth
        Choosing a Screen Bit Depth

    Reducing the Number of Colors in an Image
        Using rgb2ind
        Reducing Colors in an Indexed Image
        Dithering

    Converting Color Data Between Color Spaces
        Converting Between Device-Independent Color Spaces
        Performing Profile-Based Conversions
        Converting Between Device-Dependent Color Spaces

Functions -- By Category

    Image Input, Output, and Display
    Spatial Transformation and Registration
    Image Analysis and Statistics
    Image Enhancement and Restoration
    Linear Filtering and Transforms
    Morphological Operations
    Region-Based, Neighborhood, and Block Processing
    Colormap and Color Space Functions
    Miscellaneous Functions

Functions -- Alphabetical List

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