[whatwg] HTML5 video <source> dimensions and bitrate

Chris Double chris.double at double.co.nz
Fri Aug 13 19:30:29 PDT 2010

On Sat, Aug 14, 2010 at 2:26 PM, Eric Carlson <eric.carlson at apple.com> wrote:
>  mozDownloadRate - What are the units, bit per second?

Bytes per second.

>  mozPlaybackRate - Is this the movie's data rate (total bytes / duration)?

Yes. This and mozDownloadRate were available internally already for
'can play through' calculations so I just exposed what we already
have. 'mozPlaybackRate' is a bad name though since there is already a
concept of 'playback rate' for playback speed.

>  mozFrameCount - What do you propose a UA report for a partually downloaded VBR movie, or for a movie in a container that doesn't have a header (ie. one where you don't know the fame count until you have examined every byte in the file)?

This is another bad name for what it actually is. It's a count of each
frame as it is displayed. So the inverse of mozDroppedFrames really -
it probably should be mozDisplayedFrames or something. I'm not sure if
it's useful but it's the original stat I had for computing framerate
playback in JavaScript in my tests.


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