nextcloud/lib/private/preview/svg.php

<?php
/**
 * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
 * This file is licensed under the Affero General Public License version 3 or
 * later.
 * See the COPYING-README file.
 */
namespace OC\Preview;

use Imagick;

if (extension_loaded('imagick')) {

	$checkImagick = new Imagick();

	if(count($checkImagick->queryFormats('SVG')) === 1) {

		class SVG extends Provider {

			public function getMimeType() {
				return '/image\/svg\+xml/';
			}

			public function getThumbnail($path,$maxX,$maxY,$scalingup,$fileview) {
				try{
					$svg = new Imagick();
					$svg->setBackgroundColor(new \ImagickPixel('transparent'));

					$content = stream_get_contents($fileview->fopen($path, 'r'));
					if(substr($content, 0, 5) !== '<?xml') {
						$content = '<?xml version="1.0" encoding="UTF-8" standalone="no"?>' . $content;
					}

					$svg->readImageBlob($content);
					$svg->setImageFormat('png32');
				} catch (\Exception $e) {
					\OC_Log::write('core', $e->getmessage(), \OC_Log::ERROR);
					return false;
				}


				//new image object
				$image = new \OC_Image();
				$image->loadFromData($svg);
				//check if image object is valid
				return $image->valid() ? $image : false;
			}

		}

		\OC\Preview::registerProvider('OC\Preview\SVG');
	}
}