using imtool and imcontrast functions

Hi,

I am trying to change the contrast of a jpg image. I tried using imtool function after reading the image by typing J = imtool(I). Although I managed to open image (I) on imtool but the contrast taps were not activated for some reason. I also tried using imcontrast and hist functions but with no success. Would some please advice regarding this?

Azzar

[KAE]

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