National Instruments IMAQ Vision for Measurement Studio - page 45

Chapter4 BlobAnalysis

IMAQVision for LabWindows/CVI User Manual 4-6 ni.com

IMAQ_MAX_SEGMENT_LEFT_COLUMN leftmostx-coordinate of longest horizontal line segment

in a particle

IMAQ_MAX_SEGMENT_TOP_ROW y-coordinateof longest ho rizontal line segment

IMAQ_PERIMETER lengthof the outer contour of the particle in u ser-defined

units

IMAQ_PERIMETER_OF_HOLES perimeterof all holes in user-defined units

IMAQ_SIGMA_X sumof the x-coordinatesf or each pixelof the particle

IMAQ_SIGMA_Y sumof the y-coordinatesf or each pixelof the particle

IMAQ_SIGMA_XX sumof the squared x-coordinatesf or each pixelof the

particle

IMAQ_SIGMA_YY sumof the squared y-coordinatesf or each pixelof the

particle

IMAQ_SIGMA_XY sumof the product of the x-coordinate and y-coordinate

foreach pixelof the particle

IMAQ_PROJ_X sumof thevertical segments in a particle

IMAQ_PROJ_Y sumof the ho rizontal segmentsin a particle

IMAQ_INERTIA_XX inertiam atrix coefficientin XX

IMAQ_INERTIA_YY inertiam atrix coefficientin YY

IMAQ_INERTIA_XY inertiam atrix coefficientin XY

IMAQ_MEAN_H meanlengt h of horizontal segments

IMAQ_MEAN_V meanlength of vertical segments

IMAQ_MAX_INTERCEPT lengthof the longest segmentof th eco nvexhull of the

particle

IMAQ_MEAN_INTERCEPT meanlength of the chords in a particle perpendicular to

itsm ax intercept

IMAQ_ORIENTATION directionof t he major axis of a particle

IMAQ_EQUIV_ELLIPSE_MINOR totallength of t he minor axis of the ellipse having the

same areaas the particle and a major axis equal to half

them ax intercept

Table4-1. Particle Measurements (Continued)

Measurement Description

Contents

Main IMAQ Page Important Information Warranty Copyright Trademarks WARNINGREGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS Conventions Contents Chapter 1 Introduction to IMAQ Vision Chapter 2 Getting Measurement-Ready Images Chapter 3 Grayscale and Color Measurements Chapter 4 Blob Analysis Chapter 5 Machine Vision Page Introduction to IMAQ Vision About IMAQ Vision Documentation and Examples Application Development Environments IMAQ Vision Function Tree Page IMAQ Machine Vision Function Tree Creating IMAQ Vision Applications Chapter1 Introductionto IMAQ Vision Figure1-2. InspectionSteps for Building a Vision Application IMAQVision for LabWindows/CVI User Manual 1-6 ni.com Getting Measurement-Ready Images Set Up Your Imaging System Calibrate Your Imaging System Create an Image Page Source and Destination Images AcquireorReadanImage Acquiring an Image Reading a File Converting an Array to an Image Display an Image Attach Calibration Information Analyze an Image Improve an Image Lookup Tables Filters Convolution Filter Nth Order Filter Grayscale Morphology FFT Page Complex Image Operations Grayscale and Color Measurements Define Regions of Interest Interactively Defining Regions Page Page Page Page Programmatically Defining Regions Defining Regions with Masks Measure Grayscale Statistics Measure Color Statistics Figure3-4. Primary Components of a Color Image Comparing Colors Learning Color Information Choosing the Right Color Information Specifying the Color Information to Learn Using the Entire Image Using a Region in the Image Using Multiple Regions in the Image Choosing a Color Representation Sensitivity Ignoring Learned Colors Blob Analysis Correct Image Distortion Create a Binary Image Improve the Binary Image Removing Unwanted Blobs Separating TouchingBlobs Improving Blob Shapes Make Particle Measurements Page Page Convert Pixel Coordinates to Real-World Coordinates Machine Vision Locate Objects to Inspect UsingEdgeDetectiontoBuildaCoordinateTransform Page Using Pattern Matching to Build a Coordinate Transform Page Chapter5 MachineVision NationalInstruments Corporation 5-7 IMAQVision for LabWindows/CVI User Manual ChoosingaMethodtoBuildtheCoordinateTransform Figure5-4. Buildinga Coordinate Transform Set Search Areas Interactively Defining Regions Programmatically Defining Regions Find Measurement Points Finding Features Using Edge Detection Finding Lines or Circles Figure5-5. Findinga Straight Feature Finding Edge Points Along One Search Contour Finding Edge Points Along Multiple Search Contours Finding Points Using Pattern Matching Defining and Create Good TemplateImages Symmetry Feature detail Positional information Background information Trainingthe Pattern Matching Algorithm Defining a Search Area Setting Matching Parameters and Tolerances Match Mode Minimum Contrast Rotation Angle Ranges Testingthe Search Algorithm on Test Images Using a Ranking Method to Verify Results Finding Points Using Color Pattern Matching Defining and Creating Good Color TemplateImages Color Information Symmetry Feature Detail Positional Information Trainingthe Color Pattern Matching Algorithm Defining a Search Area Setting Matching Parameters and Tolerances Color Sensitivity Search Strategy Color Score Weight Minimum Contrast Rotation Angle Ranges Testingthe Search Algorithm on Test Images Finding Points Using Color Location Convert Pixel Coordinates to Real-World Coordinates Make Measurements Distance Measurements Analytic Geometry Measurements Instrument Reader Measurements Display Results Page Calibration Perspective and Nonlinear Distortion Calibration Defining a Calibration Template Defining a Reference Coordinate System Page Page Learning Calibration Information Specifying Scaling Factors Choosing a Region of Interest Choosing a Learning Algorithm Using the Learning Score Learning the Error Map Learning the Correction Table Setting the Scaling Method Calibration Invalidation Simple Calibration Save Calibration Information Attach Calibration Information A Technical Support Resources Web Support NI Developer Zone Customer Education System Integration Worldwide Support Glossary Numbers/Symbols A B C Page D E F G H I Page J K L M N O P Page Q R S T Page Index A B C D E F G H I Page Page L M N O P R S T V W Z