We have created a module to create BlurHash strings for images while uploading in ProcessWire. This blurry images will be saved in the database because they are very small (20-30 characters) and can be used for Data-URL's as placeholders for image-lazy loading.
https://github.com/blue-tomato/ImageBlurhash
E.g. where we use this in production:
https://www.blue-tomato.com/en-INT/blue-world/
https://www.blue-tomato.com/en-INT/blue-world/products/girls-are-awesome/
https://www.blue-tomato.com/en-INT/buyers-guides/skateboard/skateboard-decks/
https://www.blue-tomato.com/en-INT/team/anna-gasser/