Bring new life to old photos by automatically colorizing them using the Algorithmia API. Coloring is based on deep learning models by Algorithmia. Models are exposed as API,once you signup you get 5000 as signup bonus.5000 credits are free every month.
Visit here Wallpics
If you don’t want to use API,you can visit http://demos.algorithmia.com/colorize-photos/ to colorize it.