PHP | Image orientation with svg support and tolerance

orientation.php

<?php
function get_orientation($image_file, $tolerance = '1.5') {
    // First let us determine what kind of file we are dealing with
    $path_parts = pathinfo($image_file);
    $extension = $path_parts['extension'];
    if ( $extension == 'svg' ) {
        // Vector svg
        $xmlget = simplexml_load_file($image_file);
        $xmlattributes = $xmlget->attributes();
        $width = (string) $xmlattributes->width;
        $width = trim($width, "px"); // remove px after dimension
        $height = (string) $xmlattributes->height;
        $height = trim($height, "px");
    } else {
        // Bitmap image
        list($width, $height) = getimagesize($image_file);
    }
    // Now we have a width and height let us determine the orientation
    if ( $width > $height ) {
        // Landscape
        if ( $width / $height >= $tolerance ) {
            // If the ratio is more than 1.5 it is indeed a proper landscape image
            $orientation = 'landscape';
        } else {
            // if the ratio is less than 1.5 it is practically square
            $orientation = 'square';
        }
    } elseif ( $height > $width ) {
        // Portrait
        if ( $height / $width >= $tolerance ) {
            $orientation = 'portrait';
        } else {
            $orientation = 'square';
        }
    } else {
        // The width and height must be the same
        $orientation = 'square';
    }
    return $orientation;
}
?>

Image orientation

A client site had a list of customer logos in an SVG format, some quite obviously landscape or portrait and some pretty much square, I created this function so I could apply an orientation class to each image and then set the width or height accordingly.

For example; .landscape { width: 200px; height: auto; } or .portrait { height: 100px; width: auto; }

WordPress usage

Add the function to your theme's functions.php file.

Use get_orientation($image_file) in your template file.

Example:

$image_file = get_sub_field('logo');
$orientation = get_orientation($image_file);
echo '<img src="' . $image_file . '" class="' .  $orientation . '" />;

Tolerance

Simply, this is how relaxed the function is about the image being classed as square.

I added this flexibility as I had one image that was 100 pixels wide by 95 pixels tall. Strictly speaking it's a landscape image, though visually it's pretty much square. In this instance the ratio was 1.05. I decided, visually, the ratio should be around 1.5. However this can be altered to suit, simply pass in a second variable like so:

$orientation = get_orientation($image_file, '2.1');

// or make it strict like this...

$orientation = get_orientation($image_file, '1');

Bitmap support

The function is geared toward svg images since they can be scaled without pixelisation. However, it will return a class for bitmap images too.

Mime

As you can tell I used pathinfo to determine file extension as opposed to mime. This gave me the desired result. I tried various mime identification php functions without consistent success.