The imageconvolution() function
Syntax
bool imageconvolution (img, matrix, div, offset )
Parameters
img: Create image with imagecreatetruecolor() function.
matrix: A 3x3 matrix is an array of three arrays of three floats.
div: Divisor of the result of the convolution, used for normalization.
offset: The color offset.
Return
The imageconvolution() function returns True on success or False on failure.
Example
The following is an example
<?php
$img = imagecreatefromgif('https://www.tutorialspoint.com/images/html.gif');
$arr = array(array(2, 0, 1), array(-1, -1, 0), array(0, 0, -1));
imageconvolution($img, $arr, 1, 127);
header('Content-Type: image/png');
imagepng($img, null, 9);
?>Output
The following is the output
Example
Let us see another example with different parameter values for the same image. You can easily spot the difference now:
<?php
$img = imagecreatefromgif('https://www.tutorialspoint.com/images/html.gif');
$arr = array(array(3, 2, 1), array(0, 1, 0), array(1, -1, -1));
imageconvolution($img, $arr, 3, 110);
header('Content-Type: image/png');
imagepng($img, null, 9);
?>Output
The following is the output
