PHP | imagedestroy() Function

The imagedestroy() function is an inbuilt function in PHP which is used to destroy an image and frees any memory associated with the image.

Syntax:

bool imagedestroy( resource $image )

Parameters: This function accepts a single parameter $image which holds the name of image.

Return Value: This function returns TRUE on success and FALSE on failure.

Below examples illustrate the imagedestroy() function in PHP:

Example 1: Destroying image after using it.

<?php

// Load the png image
$im = imagecreatefrompng(
'https://media.geeksforgeeks.org/wp-content/uploads/20200123135210/geeksforgeeksinverted.png');

// Crop the image
$cropped = imagecropauto($im, IMG_CROP_BLACK);

// Convert it to a png file
header('Content-type: image/png');
imagepng($cropped);

// Destroy the cropped image to deallocate the memory
imagedestroy($cropped);
?>

Output:

$cropped variable is destroy by the end line
and you can't access it after that line.

Example 2: Checking if the variable is destroyed.

<?php

// Load the png image
$im = imagecreatefrompng(
'https://media.geeksforgeeks.org/wp-content/uploads/20200123135210/geeksforgeeksinverted.png');

header('Content-type: image/png');

// Destroy the image to deallocate the memory
imagedestroy($im);

// Try to access the destroyed variable
imagepng($im);
?>

Output:

PHP log will give a error as the variable is destroyed. PHP Warning:  imagepng(): supplied resource is not a valid Image resource.

Reference: https://www.php.net/manual/en/function.imagedestroy.php