Videor is an online web application for making short videos. Its UI allows the user to place various elements to make up the video. The finished video can be exported directly from the browser.

Work in progress: nothing is done.

At the core of this application is the MediaRecorder API.

The video gets built up using a canvas element. The MediaRecorder instance uses the canvas element to generate frames of the video. I have prototyped this in html-video.

captureStream has a frameRate argument. The documentation says when 0 is supplied, the requestFrame method can be used to tell MediaRecorder to use the current state of the canvas for a frame. This seems preferable to setting the frame-rate upfront, because then the video must be generated in real time. The video will lag in case the code for generating the frames can't keep up with the desired frame rate. But even if it can, the video cannot be generated faster than real-time. Ideally, I'd find a way to generate the frames as fast as they can be generated and generate the video faster than its intended runtime, but also prevent the video from being laggy in case the frames can't be generated in real-time.