Comparison of chi-square and join-count methods for evaluating digital image data

Author

Chuang, Keh-Shih ; Huang, H.K.

Author_Institution

Dept. of Radiol. Sci., California Univ., Sch. of Med., Los Angeles, CA, USA

Volume

11

Issue

1

fYear

1992

fDate

3/1/1992 12:00:00 AM

Firstpage

28

Lastpage

33

Abstract

The significance of each bit of the pixel in digital image data from various radiological modalities is tested to determine the contrast resolution. Two statistical methods, join-count statistic and chi-square goodness of fit test, are used to perform the test. Join-count statistic is used to measure the spatial coherence among pixels, while the chi-square test is used to determine if the bit data are randomly distributed. A residual image is formed by subtracting an original image from its smoothed version. The contrast revolution is determined by applying both statistics on each bit plane of the residual image starting from the least significant bit up to the bit plane whose statistic does not show a random pattern. Images from three digital modalities, computerized tomography, magnetic resonance, and computed radiography, are used to evaluate the gray-level dynamic range. Both methods are easy to implement and fast to perform

Keywords

biomedical NMR; computerised tomography; diagnostic radiography; radiology; bit plane; chi-square method; computed radiography; computerized tomography; contrast revolution; digital image data evaluation; gray-level dynamic range; join-count method; magnetic resonance; medical diagnostic imaging; pixel; random pattern; residual image; spatial coherence measurement; statistical methods; Computed tomography; Digital images; Image resolution; Performance evaluation; Pixel; Spatial coherence; Spatial resolution; Statistical analysis; Statistical distributions; Testing;

fLanguage

English

Journal_Title

Medical Imaging, IEEE Transactions on

Publisher

ieee

ISSN

0278-0062

Type

jour

DOI

10.1109/42.126907

Filename

126907