Image Processing Toolbox

Getting Started

Preface

What Is the Image Processing Toolbox?

What Can You Do with the Image Processing Toolbox?

New Features in Version 2.2

Related Products

Post Installation Notes

About This Manual

User Experience Levels

Words You Need to Know

Typographical Conventions

Image Processing Toolbox Typographical Conventions

Image Processing Demos

MATLAB Newsgroup

Getting Started

Overview

Exercise 1 -- Some Basic Topics

1. Read and Display an Image

2. Check the Image in Memory

3. Perform Histogram Equalization

4. Write the Image

5. Check the Contents of the Newly Written File

Exercise 2 -- Advanced Topics

1. Read and Display An Image

2. Perform Block Processing to Approximate the Background

3. Display the Background Approximation As a Surface

4. Resize the Background Approximation

5. Subtract the Background Image from the Original Image

6. Adjust the Image Contrast

7. Apply Thresholding to the Image

8. Use Connected Components Labeling to Determine the Number of Objects in the Image

9. Examine an Object

10. Compute Feature Measurements of Objects in the Image

11. Compute Statistical Properties of Objects in the Image

Where to Go From Here

Online Help

Toolbox Demos

Using the Image Processing Toolbox

Introduction

Overview

Words You Need to Know

Images in MATLAB and the Image Processing Toolbox

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

Working with Image Data

Reading a Graphics Image

Writing a Graphics Image

Querying a Graphics File

Converting The Image Type of Images

Working with uint8 and uint16 Data

Converting The Storage Class of Images

Converting the Graphics File Format of an Image

Coordinate Systems

Pixel Coordinates

Spatial Coordinates

Displaying and Printing Images

Overview

Words You Need to Know

Displaying Images with imshow

Displaying Indexed Images

Displaying Intensity Images

Displaying Binary Images

Displaying RGB Images

Displaying Images Directly from Disk

Special Display Techniques

Adding a Colorbar

Displaying Multiframe Images

Displaying Multiple Images

Setting the Preferences for imshow

Zooming in on a Region of an Image

Texture Mapping

Printing Images

Troubleshooting

Geometric Operations

Overview

Words You Need to Know

Interpolation

Image Types

Image Resizing

Image Rotation

Image Cropping

Neighborhood and Block Operations

Overview

Words You Need to Know

Types of Block Processing Operations

Sliding Neighborhood Operations

Padding of Borders

Linear and Nonlinear Filtering

Distinct Block Operations

Overlap

Column Processing

Sliding Neighborhoods

Distinct Blocks

Linear Filtering and Filter Design

Overview

Words You Need to Know

Linear Filtering

Convolution

Padding of Borders

The filter2 Function

Separability

Higher-Dimensional Convolution

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

Overview

Words You Need to Know

Fourier Transform

Definition of Fourier Transform

The Discrete Fourier Transform

Applications

Discrete Cosine Transform

The DCT Transform Matrix

The DCT and Image Compression

Radon Transform

Using the Radon Transform to Detect Lines

The Inverse Radon Transform

Analyzing and Enhancing Images

Overview

Words You Need to Know

Pixel Values and Statistics

Pixel Selection

Intensity Profile

Image Contours

Image Histogram

Summary Statistics

Feature Measurement

Image Analysis

Edge Detection

Quadtree Decomposition

Image Enhancement

Intensity Adjustment

Noise Removal

Binary Image Operations

Overview

Words You Need to Know

Neighborhoods

Padding of Borders

Displaying Binary Images

Morphological Operations

Dilation and Erosion

Related Operations

Object-Based Operations

4- and 8-Connected Neighborhoods

Perimeter Determination

Flood Fill

Connected-Components Labeling

Object Selection

Feature Measurement

Image Area

Euler Number

Lookup Table Operations

Region-Based Processing

Overview

Words You Need to Know

Specifying a Region of Interest

Selecting a Polygon

Other Selection Methods

Filtering a Region

Filling a Region

Color

Overview

Words You Need to Know

Working with Different Screen Bit Depths

Reducing the Number of Colors in an Image

Using rgb2ind

Using imapprox

Dithering

Converting to Other Color Spaces

NTSC Color Space

YCbCr Color Space

HSV Color Space

Reference

Function Reference

Functions by Category

applylut

bestblk

blkproc

brighten

bwarea

bweuler

bwfill

bwlabel

bwmorph

bwperim

bwselect

cmpermute

cmunique

col2im

colfilt

colorbar

conv2

convmtx2

convn

corr2

dct2

dctmtx

dilate

dither

double

edge

erode

fft2

fftn

fftshift

filter2

freqspace

freqz2

fsamp2

fspecial

ftrans2

fwind1

fwind2

getimage

gray2ind

grayslice

histeq

hsv2rgb

idct2

ifft2

ifftn

im2bw

im2col

im2double

im2uint8

im2uint16

imadjust

imapprox

imcontour

imcrop

imfeature

imfinfo

imhist

immovie

imnoise

impixel

improfile

imread

imresize

imrotate

imshow

imwrite

ind2gray

ind2rgb

iptgetpref

iptsetpref

iradon

isbw

isgray

isind

isrgb

makelut

mat2gray

mean2

medfilt2

montage

nlfilter

ntsc2rgb

ordfilt2

phantom

pixval

qtdecomp

qtgetblk

qtsetblk

radon

rgb2gray

rgb2hsv

rgb2ind

rgb2ntsc

rgb2ycbcr

rgbplot

roicolor

roifill

roifilt2

roipoly

std2

subimage

truesize

uint8

uint16

warp

wiener2

ycbcr2rgb

zoom

Working with Function Functions

Passing an M-File Function to a Function Function

Passing an Inline Object to a Function Function

Passing a String to a Function Function


 Getting Started