diff --git a/reference/imagick/imagick/sigmoidalcontrastimage.xml b/reference/imagick/imagick/sigmoidalcontrastimage.xml index c17490a45fc6..8f094f64570f 100644 --- a/reference/imagick/imagick/sigmoidalcontrastimage.xml +++ b/reference/imagick/imagick/sigmoidalcontrastimage.xml @@ -15,19 +15,21 @@ floatbeta intchannelImagick::CHANNEL_DEFAULT - + 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 + function without saturating highlights or shadows. alpha indicates + how much to increase the contrast: 0.00 is none; 3.00 is + typical; 20.00 is pushing it. + beta indicates where midtones fall in the resultant + image: 0.00 is white; 0.50 is + middle-gray; 1.00 is black. Set sharpen to &true; to increase the image contrast otherwise the contrast is reduced. - - + + See also ImageMagick - v6 Examples - Image Transformations — Sigmoidal Non-linearity Contrast - + Examples -- Color Modifications — Sigmoidal Non-linearity Contrast. + @@ -37,33 +39,35 @@ sharpen - - If true increase the contrast, if false decrease the contrast. - + + If &true; increase the contrast, if &false; decrease the contrast. + alpha - - The amount of contrast to apply. 1 is very little, 5 is a significant amount, 20 is extreme. - + + The amount of contrast to apply. 1.00 is very little, 5.00 + is a significant amount, 20.00 is extreme. + beta - Where the midpoint of the gradient will be. This value should be in the range 0 to 1 - multiplied by the quantum value for ImageMagick. + Where the midpoint of the gradient will be. This value should be in the range 0.00 + to 1.00 - multiplied by the quantum value for ImageMagick. channel - + Which color channels the contrast will be applied to. - + @@ -86,31 +90,28 @@ &reftitle.examples; - - - - Create a gradient image using <function>Imagick::sigmoidalContrastImage</function> - suitable for blending two images together smoothly, with the blending - defined by $contrast and $the midpoint - - + + + Create a gradient image using <function>Imagick::sigmoidalContrastImage</function> + suitable for blending two images together smoothly, with the blending + defined by <parameter>alpha</parameter> and <parameter>beta</parameter> + + newPseudoImage($width, $height, 'gradient:black-white'); $quanta = $imagick->getQuantumRange(); - $imagick->sigmoidalContrastImage(true, $contrast, $midpoint * $quanta["quantumRangeLong"]); + $imagick->sigmoidalContrastImage(true, $alpha, $beta * $quanta["quantumRangeLong"]); return $imagick; } - -?> ]]> - - - + +