[whatwg] Limiting the amount of downloaded but not watched video

Chris Pearce chris at pearce.org.nz
Sat Jan 22 12:47:16 PST 2011

On 22/01/2011 11:57 p.m., Philip Jägenstedt wrote:
> I agree that there must exist a buffering strategy between 
> strategy=metadata and strategy=auto, but it's not clear that this must 
> be exposed as a preload state. The only difference between 
> preload=metadata and preload=state3 would be that preload=state3 would 
> expect the user to start playing soon and start buffering in 
> anticipation of that. Firefox has supported preload=metadata (and 
> earlier, lack of autobuffer attribute) for a long time. Is it a 
> problem in Firefox that playback is slow to start because too little 
> was buffered before suspending? 

Firefox's media decoder goes into its internal buffering mode when you 
play a preload=metadata video. Playback will actually start when one of 
the following is true: 30 seconds has passed, 30 seconds of the video 
data is buffered (as estimated using the average bitrate, if known), or 
the media is in readyState HAVE_ENOUGH_DATA. We could probably be a bit 
less conservative, and start playback earlier.

Chris P.

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