A Perch CMS template filter to detect whether an image is portrait or landscape orientation. Written by Jay George.

image_orientation_detection.php

/* GROUP IMAGE ORIENTATION DETECTION
=================================================== */
class PerchTemplateFilter_image_orientation_detection extends PerchTemplateFilter 
{
    /* Notes...
        You may want to do something different if the image is landscape e.g. span 2 columns in a CSS grid rather than 1
        - Assumes your template image has an ID of `image`
        - e.g. `<div class="c-photo-grid__item c-photo-grid__item--<perch:content id="image" filter="image-orientation-detection" />">`
        This would either output `c-photo-grid__item--landscape` or `c-photo-grid__item--portrait`
    */
    public function filterAfterProcessing($value, $valueIsMarkup = false)
    {
        if($this->content['image']['w'] > $this->content['image']['h']) {
            return 'landscape';
        } else {
            return 'portrait';
        }
    }
}
PerchSystem::register_template_filter('image-orientation-detection', 'PerchTemplateFilter_image_orientation_detection');