Streamline: custom video pipelines with Cloudflare Stream and Workers

Cloudflare Stream is a powerful broadcasting platform that, for many of our customers, just works. But what if you wanted to render dynamic annotations on a livestream or create an alternate version of a hosted video with burned-in subtitles? You would need to run a custom video pipeline. Today, we’re releasing a new developer playground, Streamline, that demonstrates how you can build a system to deliver these bespoke video experiences on Cloudflare’s Developer Platform. We’ll walk you through how Streamline leverages Workers, Containers, and several media protocols to modify video — and immediately publish that output as livestream or new hosted video. You’ll also have the opportunity to try it for your projects. A processing pipeline needs a durable, long-running environment that can run specialized, compiled code with predictable memory and CPU capacity. Video streams can run for minutes or hours, so the media process needs a lifecycle independent of the request that started it. An application should be able to start a pipeline, send its input, inspect it, and stop it without needing to keep a single request open for the entire duration. Cloudflare provides the primitives we need. Containers are long-lived runtimes suitable for media processing. Durable Objects…