Concrete5 - Add thumbnail types programmatically

add_thumbnails.php

<?php
// Tested with Concrete5 version 8.2.0
$type = \Concrete\Core\File\Image\Thumbnail\Type\Type::getByHandle('custom_100x100px');
if(!is_object($type)){
	$typeEntity = new \Concrete\Core\Entity\File\Image\Thumbnail\Type\Type();
	$width = 100;  // px
	$height = 100;  // px || null for auto
	if ($height > 0) {
		$typeEntity->setHeight($height);
	}
	if ($width > 0) {
		$typeEntity->setWidth($width);
	}
	$typeEntity->setName('Thumb 100 x 100 px');
	$typeEntity->setHandle('custom_100x100px');
	$typeEntity->setSizingMode('proportional'); // values: proportional, exact
	$typeEntity->save();
}