Title :
Focus quality assessment. I. Numerical measurement
Author :
Lourens, J.G. ; du Toit, T.C.
Author_Institution :
Stellenbosch Univ., South Africa
fDate :
3/1/1989 12:00:00 AM
Abstract :
A simple algorithm is described that determines the focus quality of an image by measuring the maximum brightness gradient present in it. Measurements on actual television pictures are correlated with subjective focus evaluations on the CCIR five-point scale. The excellent correlation between measurement and subjective evaluation indicates the usefulness of the algorithm.<>
Keywords :
brightness; optical variables measurement; television reception; CCIR five-point scale; TV pictures measurement; algorithm; correlation; focus quality; image quality; maximus brightness gradient measurement; numerical measurement; subjective focus evaluations; Apertures; Frequency; H infinity control; Integral equations; Lenses; Low pass filters; Phase measurement; Quality assessment; Radio access networks; Transfer functions;
Journal_Title :
Broadcasting, IEEE Transactions on
