SDL Web 8 - How to get custom ECL metadata exposed?
In your ECL implementation, you define your metadata’s XML schema:
Another property will populate this schema:
Deploy this in your DEV environment ~/ProgramData/SDL/SDL Tridion/External Content Library/AddInPipeline/Addins/CustomProvider and restart your SDL services. You should now be able to see the change reflected in SDL Web.
Simply add this multimedia image to a component with a component presentation using DD4T’s dynamic generate content and you should now be able to see this content on your web app.