Two FFGL plugins: an effect that prints your clip onto 35 mm, 16 mm or Super 8 film, and a source that runs the countdown leader on it. The holes, frame lines, anamorphic squeeze and soundtracks are where the published standards put them, and every frame keeps the picture it was exposed with, so a moving strip carries the clip's recent past across the screen. The optical track wiggles with the music, and the countdown and the sync flash land on the beat or the bar if you ask them to.
This demo runs the plugin's own C++, compiled to WebAssembly, and its shaders in your browser, so it needs JavaScript and WebGL2. The plugin itself, its source and its downloads are on its repository.