Hey everyone, wanted to share an awesome article and recent announcement from Cloudinary with you all.
Tl;dr: Cloudinary released a free and open source tool which tells you what the optimal number of image versions that you need for a specific image for every device you are targeting in the spectrum. At some level it compares between [filetype / filesize gain / image size / device resolution] in order to calculate.
For user generated content you can use their API to have them calculate and create the image sizes you need and then send back the new srcset= attributes you’ll need to add as a JSON response. The response are based on parameters that you send to Cloudinary with your request.