ImageViewer-omeka-module/view/common/block-layout/imageViewer.phtml

<?php if ($zoom == true) {
	$this->headScript()->appendFile($this->assetUrl('vendor/wheelzoom/wheelzoom.js',
																									'ImageViewer'));
} ?>

<div class="wheelzoom-wrap" style="position:relative;">

	<?php
		if ($title !== false && $title !== "") {
			$title = sprintf('<p id="wheelzoom-title">%s</p>', $title);
		} else {
			$title = false;
		}
	?>

	<style>
		.archive-img {
			width: <?= $width ?>px;
		}
	</style>

	<div class="archive-img">
		<img id="<?= $id ?>"
				 src="<?= $image ?>"
		/>
		<?php if ($zoom == true) { ?>
			<div
				style="font-size: 0.75em; color:white; background-color: gray; padding-left: 1em">
				You can zoom this image
			</div>
		<?php } ?>
	</div>

	<?php if ($zoom == true) { ?>
		<script>
		$(document).ready(function(){
			wheelzoom(document.querySelector('#<?= $id ?>'));
		});
		</script>
	<?php } ?>

</div>