Syntax:bool Imagick::sigmoidalContrastImage (bool $sharpen, float $alpha, float $beta, int $channel = Imagick::CHANNEL_DEFAULT)
Parameters:this function takes four options as above and described below: - $sharpen:specifies whether to increase or decrease the contrast. A true value increases contrast, and a false value decreases contrast.
- $alpha:determines the level of contrast to be applied.
- $beta: specifies the midpoint of the gradient.
- $channel:This is an optional parameter that contains a channel constant. The default is Imagick::CHANNEL_DEFAULT.
Return Value:This function returns TRUE on success.Exceptions:this function throws an ImagickException on error.The following programs illustrate the Imagick::sigmoidalContrastImage()function in PHP:Program 1 :
// Create a new imagick object $imagick = new Imagick ( ’ https://media.engineerforengineer.org/wp -content / uploads / engineerfor engineer-13.png ’ );
// Adjust contrast $imagick -> sigmoidalContrastImage (true, 10, 32000);
// Show output header ( "Content-Type: image / png" ); echo $imagick -> getImageBlob(); ?> Output: Program 2:
// Create new imagick object $imagick = new Imagick ( ’ https://media.engineerforengineer.org/wp-content/uploads/engineerforengineer-13.png ’ );
// Adjust contrast $imagick -> sigmoidalContrastImage (false, 10, 31000);
// Show output header ( "Content-Type: image / png" ); echo $imagick -> getImageBlob(); ?> Output: Link: https://www.php.net/manual/en/imagick.sigmoidalcontrastimage.php
