This is a simple app that uses opencv to apply a few basic image filters i was tinkering with. The transformations interpolate between given RGB anchors with a spline curve. The code is very flexible. If you'd like to make some of your own, you can see the source code here: https://github.com/mjjurow/ImageFilter
This is deployed on GCP App Engine as a flask app here: https://simple-image-filter.uk.r.appspot.com/
Here's a screen shot if you dont want to go try it out on your own: