National Instruments Image Acquisition Software - page 40

Appendix A StillColor

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National Instruments Corporation A-3 NI-IMAQ User Manual

All of the traditional ways to separate the two signals result in visual

artifacts on the final picture. Techniques such as frequency-band filtering

or comb filtering can minimize some of these artifacts, but most techniques

are optimized to obtain the best picture for visualization of a continuous

acquisition. The composite color formats are designed so that artifacts

resulting from one frame are almost cancelled by artifacts in following

frames. This system takes advantage of the slow response time of the

human eye to obscure most of these problems.

The situation is different in a single frame acquisition where a single image

is needed. A single image usually clearly shows the result of a bad

color/luminance separation. Typical weakness of traditional separation

techniques are:

• Reduced luminance bandwidth, resulting in a blurry image.

• Cross-color modulation where rapidly changing colors affect the

luminance of the image, as shown on the edges of the parrot’s head

in Figure A-1.

• Cross-luminance modulation where rapidly changing luminance

(stripes) results in irritating random color patterns, as shown on the

black and white stripes around the parrot’s eye in FigureA-1.

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Contents

Main Page Important Information Warranty Copyright Trademarks WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS Contents About This Manual Chapter 1 Introduction to NI-IMAQ Chapter 2 Software Overview Page Figures Tables About This Manual How to Use the NI-IMAQ Manual Set Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Customer Communication Introduction to NI-IMAQ About the NI-IMAQ Software Application Development Environments Fundamentals of Building Applications with NI-IMAQ The NI-IMAQ Libraries Creating an Application Sample Programs Software Overview Generic Functions High-Level Functions Snap Functions Grab Functions Ring and Sequence Functions Signal I/O Functions Miscellaneous Functions Low-Level Functions Acquisition Functions Attribute Functions Buffer Management Functions Interface Functions Utility Functions Programming with NI-IMAQ High-Level Functions Low-Level Functions Establishing Interface Connections and Sessions Interface Functions Session Functions Managing Buffers Camera Attributes NI-IMAQ Status Signals Introductory Programming Examples High-Level Snap Functions High-Level Grab Functions The hlgrab.c example demonstrates how to perform a grab using High-Level Sequence Functions High-Level Ring Functions Page High-Level Signal I/O Functions Advanced Programming Examples Performing a Snap Using Low-Level Functions Performing a Grab Using Low-Level Functions Performing a Sequence Acquisition Using Low-Level Functions Performing a Ring Acquisition Using Low-Level Functions StillColor Snap Programming Page A StillColor StillColor StillColor Composite Traditional Color Decoding Page Page Why StillColor? Composite Color Acquisition StillColor RGB RGB Color Acquisition Introduction to Color Page Image Representations RGB Color Planes Hue, Saturation, Luminance, and Intensity Planes 32-Bit HSL and HSI B Customer Communication Electronic Services Bulletin Board Support FTP Support Fax-on-Demand Support Telephone and Fax Support Country Telephone Fax Technical Support Form NI-IMAQ Hardware and Software Configuration Form National Instruments Products Other Products Documentation Comment Form Title: Edition Date: Part Number : Mail to: Technical Publications Fax to: Technical Publications Glossary Numbers/Symbols A B C D E F G H I K L M N O P R S T U V W Y Index A B C D F G H I L M N P R S T U V W