Abstract：
:The dynamic range of the gray level of a digital image is limited by the noise it contains. Two statistical methods called "runs test" and "join-count statistic" are used to measure the noise level in a digital image. A residual image is formed by subtracting an original image from its smoothed version. Theoretically, the noise level in the residual image should be identical to that in the original image. The noise level is determined by examining each bit plane of the residual image individually 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.
journal_name
Med Physjournal_title
Medical physicsauthors
Chuang KS,Huang HKdoi
10.1118/1.597058subject
Has Abstractpub_date
1993-01-01 00:00:00pages
39-45issue
1eissn
0094-2405issn
2473-4209journal_volume
20pub_type
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