Heck, I’m using ring buffers in some high performance image processing stuff right now. There’s non-constant-time processing in the pipeline, and dropping frames is acceptable if we hit some kind of pathological case where the image processing stuff can’t keep up. Pseudo-real-time is more important than processing every frame, but processing as many frames as possible is still desirable. By adjusting the size of the ring buffer relative to the input rate, we can put a bound on the maximum age of a buffered frame (camera runs at a fixed fast rate) while guaranteeing we’ll never exceed N*frame size memory usage.