Image quality in automated visual web inspection

Jyrki Laitinen

doi:10.1117/12.271250

15 April 1997 Image quality in automated visual web inspection

Jyrki Laitinen

Proceedings Volume 3029, Machine Vision Applications in Industrial Inspection V; (1997) https://doi.org/10.1117/12.271250
Event: Electronic Imaging '97, 1997, San Jose, CA, United States

Abstract

In this study the relation between the performance of an imaging unit of a web inspection system and the final image quality is discussed. The basic idea is to analyze the results of the segmentation and feature extraction of defects in sample images as a function of imaging parameters. Determination of the quality of imaging and examples of the performance of a typical imaging unit are reviewed. The effect of the image quality on segmentation of the defects and feature extraction is analyzed in two cases: (1) The detection of small and low-contrast defects in paper inspection and (2) the depth of field considerations in steel inspection. Samples picked from the industrial manufacturing process are imaged using different imaging parameters and the defect areas in the images are segmented in order to illustrate the dependence of the system performance on the quality of imaging. Several segmentation methods are applied. These include direct thresholding, edge-based filtering, matched filtering and morphological filtering. The contrast of certain type of defects can be improved before segmentation by averaging the input data line by line. The signal processing methods presented here are computationally simple due to the need for high-speed real-time implementation in practical inspection.

Citation Download Citation

Jyrki Laitinen "Image quality in automated visual web inspection", Proc. SPIE 3029, Machine Vision Applications in Industrial Inspection V, (15 April 1997); https://doi.org/10.1117/12.271250

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available