Пример #1
0
// 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
}
Пример #2
0
//  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
}