though in practice since you need to connect this to video.currentTime to get the actual frame number, perfect accuracy is yet to be reached. This value increments every time a frame is painted on screen, so theoretically it should be possible to get to 100% accuracy. Firefox has a non-standard VideoElement property video.mozPaintedFrames.

Details to follow under the specific browser headers. Browsers update video.currentTime at differing intervals.The timeupdate event on VideoElement is completely useless for frame accuracy purposes.Now, here's how things look today: General observations This subject is outside the scope of this repository, but I have test cases available for that elsewhere. Slight color differences in video / page background actually touches on another issue - browsers also tend to have issues with video color accuracy.With perfect frame accuracy the frame numbers burned into the video as well as the color should always be in sync with the elements outside the video.100% accuracy is unlikely to be possible in any of them at the time of writing, but various per-browser tricks can at least improve the situation somewhat. The purpose of this repository is to research ways to improve frame accuracy for browsers today. The current lack of frame accuracy effectively closes off entire fields of possibilities from the web, such as non-linear video editing, but it also has unfortunate effects on things as simple as subtitle rendering. Unfortunate, video.currentTime is not accurate for this purpose - a simple calculation will be slightly off most of the time in most browsers, and when it comes to making use of frame accuracy, in many cases 100% accuracy is very much a critical requirement. Now, this in itself wouldn't necessarily be a problem, as video.currentTime exists, and assuming you know the (constant) framerate of your video (or have frame timings), you should be able to calculate the number of the currently displayed frame. To begin with, there are no standard methods for getting information about the current frame in the VideoElement API. HTML5 currently has no means of obtaining perfect frame accuracy via JS APIs.

Frame accurate html5 video player