// Adjusts the contrast of an image with a non-linear sigmoidal contrast algorithm. Increase the contrast of the image using a sigmoidal transfer function without saturating highlights or shadows. Contrast indicates how much to increase the contrast (0 is none; 3 is typical; 20 is pushing it); mid-point indicates where midtones fall in the resultant image (0 is white; 50 is middle-gray; 100 is black). Set sharpen to true to increase the image contrast otherwise the contrast is reduced.
func (self *Canvas) SigmoidalContrast(sharpen bool, alpha float64, beta float64) error {
status := C.MagickSigmoidalContrastImage(self.wand, magickBoolean(sharpen), C.double(alpha), C.double(beta))
if status == C.MagickFalse {
return fmt.Errorf("Could not contrast image: %s", self.Error())
}
return nil
}
// adjusts the contrast of an image with a non-linear sigmoidal contrast algorithm. Increase the contrast of the image using a sigmoidal transfer function without saturating highlights or shadows. Contrast indicates how much to increase the contrast (0 is none; 3 is typical; 20 is pushing it); mid-point indicates where midtones fall in the resultant image (0 is white; 50 is middle-gray; 100 is black). Set sharpen to true to increase the image contrast otherwise the contrast is reduced.
func (self Canvas) SigmoidalContrast(sharpen bool, alpha float64, beta float64) error {
var incr C.MagickBooleanType
incr = C.MagickFalse
if sharpen {
incr = C.MagickTrue
}
success := C.MagickSigmoidalContrastImage(self.wand, incr, C.double(alpha), C.double(beta))
if success == C.MagickFalse {
return fmt.Errorf("Could not contrast image: %s", self.Error())
}
return nil
}