How can headers already sent error be avoided when working with imageCreate() in PHP?

When working with imageCreate() in PHP, the "headers already sent" error can be avoided by ensuring that no output is sent to the browser before calling imageCreate(). This error occurs when there is whitespace or other characters sent to the output buffer before the image creation functions. To avoid this error, make sure to call imageCreate() before any output is sent to the browser.

<?php
ob_start(); // Start output buffering
$image = imageCreate(200, 200); // Create a new image
header('Content-Type: image/png'); // Set the header for PNG image
imagePng($image); // Output the image
imagedestroy($image); // Free up memory
ob_end_flush(); // Flush the output buffer
?>