Does seeking an HTML5 video require loading the whole file?

Question

I want to randomly seek to different points in a ~30 minute video every 30 seconds. The filesize will be 100mb. When I seek does the player start loading from that point or does it have to load the entire file and then find that time within it?

Answer 1

It depends on the browser. If we are talking about a modern browser then when you seek, they will typically send a new http request to the server containing a Range: header, indicating what "chunk" of the file they want to load. This would only be for a browser utilizing http 1.1 or higher. I think if the browser supports html5 video then you can be fairly certain that they will be using http 1.1. Keep in mind though that the client will typically always be loading something . So if you seek to 5 seconds into the vid it will essentially start loading the entire thing again until another seek happens.

Answer 2

不，只要浏览器知道视频的持续时间，它就会从给定的时间戳开始加载。