Popcorn Maker brings the power of popcorn.js and its plugin system to a graphical user interface, with familiar timeline controls. Completely free and open source, popcorn maker offers a collection of useful templates, but since it’s built from standard HTML, you can customize it to your heart’s content.
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Getting Started with Popcorn.js/Popcorn-Maker.js development
Designing the Popcorn Maker
Final Cut Pro Plug-in – First Steps
Via Nicolas Weil