Korean J Oral Maxillofac Radiol.  2010 Sep;40(3):103-107.

The effects of digital image processing for noise reduction on observer performance

• Jung YC
• Choi BR
• Huh KH
• Yi WJ
• Heo MS
• Lee SS
• Choi SC

Abstract

PURPOSE
This study was performed to examine the effects of image filter on observer performance by counting the number of holes at each wedge step on a radiographic image.
MATERIALS AND METHODS
An aluminum step wedge with 11 steps ranged in thickness from 1.5 mm to 16.5 mm in 1.5 mm increments was fabricated for this study. Each step had 10 notched holes with 1.0 mm diameter on the bottom of the step wedge which were ranged in depths from 0.1 mm to 1.0 mm in 0.1 mm increments. Digital radiographic raw images of the aluminum step wedge were acquired by using CCD intraoral sensor. The images were processed using several types of noise reduction filters and kernel sizes. Three observers counted the number of holes which could be discriminated on each step. The data were analyzed by ANOVA.
RESULTS
The number of holes at each step was decreased as the thickness of step was increased. The number of holes at each step on the raw images was significantly higher than that on the processed images. The number of holes was different according to the types and kernel sizes of the image filters.
CONCLUSION
The types and kernel sizes of image filters on observer performance were important, therefore, they should be standardized for commercial digital imaging systems.

Keyword

Task performance; Radiography, Dental; Radiographic Image Enhancement

MeSH Terms

Aluminum
Noise
Radiographic Image Enhancement
Radiography, Dental
Task Performance and Analysis
Aluminum