Alternative to WebP for Thumbnail Creation

Presently to enable WebP on my VPS server is risky as it would involve re-installation of PHP that could result in more problems. Your task is to help provide functions that could convert a WebP image format into a thumbnail without the use of an intervention library. PHP 5.6.40 (cli) (built: Jan 9 2019 15:12:06) "laravel/framework": "5.4.*" Attached is an example of an image using the following encoding: data:image/webp;base64,UklGRpT9AABXRUJQVlA4IIj9................................. The requirement is to generate a thumbnail from this image.