ImagickKernel::scale

(PECL imagick >= 3.3.0)

ImagickKernel::scale — Description

Description

public ImagickKernel::scale(float $scale, int $normalizeFlag = ?): void

ScaleKernelInfo() scales the given kernel list by the given amount, with or without normalization of the sum of the kernel values (as per given flags). The exact behaviour of this function depends on the normalization type being used please see http://www.imagemagick.org/api/morphology.php#ScaleKernelInfo for details. Flag should be one of Imagick::NORMALIZE_KERNEL_VALUE, Imagick::NORMALIZE_KERNEL_CORRELATE, Imagick::NORMALIZE_KERNEL_PERCENT or not set.

Parameters

This function has no parameters.

Return Values

Examples

Example #1 ImagickKernel::scale()


<?php


    function renderKernelTable($matrix) {
        $output = "<table class='infoTable'>";
    
        foreach ($matrix as $row) {
            $output .= "<tr>";
            foreach ($row as $cell) {
                $output .= "<td style='text-align:left'>";
                if ($cell === false) {
                    $output .= "false";
                }
                else {
                    $output .= round($cell, 3);
                }
                $output .= "</td>";
            }
            $output .= "</tr>";
        }
    
        $output .= "</table>";
    
        return $output;
    }


    $output = "";
    
    $matrix = [
        [-1, 0, -1],
        [ 0, 4,  0],
        [-1, 0, -1],
    ];

    $kernel = \ImagickKernel::fromMatrix($matrix);
    $kernelClone = clone $kernel;

    $output .= "Start kernel<br/>";
    $output .= renderKernelTable($kernel->getMatrix());
    
    
    $output .= "Scaling with NORMALIZE_KERNEL_VALUE. The  <br/>";
    $kernel->scale(2, \Imagick::NORMALIZE_KERNEL_VALUE);
    $output .= renderKernelTable($kernel->getMatrix());


    $kernel = clone $kernelClone;
    $output .= "Scaling by percent<br/>";
    $kernel->scale(2, \Imagick::NORMALIZE_KERNEL_PERCENT);
    $output .= renderKernelTable($kernel->getMatrix());
    
    $matrix2 = [
        [-1, -1, 1],
        [ -1, false,  1],
        [1, 1, 1],
    ];
    
    $kernel = \ImagickKernel::fromMatrix($matrix2);
    $output .= "Scaling by correlate<br/>";
    $kernel->scale(1, \Imagick::NORMALIZE_KERNEL_CORRELATE);
    $output .= renderKernelTable($kernel->getMatrix());

    return $output; 
?>