Average gradient (AG). The AG reﬂects the ability to express the details of an image and can be used to measure the
relative clarity of the image. AG is formulated as:
This is the code AG
[dfdx,dfdy] = gradient(f) ;
M = (dfdx.^2+dfdy.^2)/2 ;
AG = mean(mean(M)) ;
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To improve the significance of the data, a comprehensive evaluation parameter was set in the experiment so that the average values of different sets of test data could be presented in a consistent manner:
where n is the sample size, Yi is the result of testing on a certain sample, and Y is the average value.
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