[MEncoder-users] Videos with fps 1000.000

[Rich Felker]

On Mon, Mar 19, 2007 at 10:33:36PM -0600, Mike Hodson wrote:
> On 3/19/07, Rich Felker <dalias at aerifal.cx> wrote:
> 
> >The correct way: each frame has a timestamp in terms of some time
> >unit. For crappy formats like WMV, the time unit is fixed at 1/1000
> >sec. (Thus the fake 1000 fps 'framerate' mplayer shows.) For good
> >formats, the time unit is specified by the file and adapted to the
> >content.
> >
> >Rich
> 
> If this is a real-time live stream, how can you pre-anticipate the
> content?

What do you mean?

> And, for that matter, how does RealVideo do it, as it too can
> vary framerate based on encoding complexity to maintain a steady
> bitrate.

This ia a very stupid bitrate control mechanism. Simply lowering the
quality of each frame hurts perceived quality much less that making
the video choppy does. Also, dropping frames does NOT generally lower
the bitrate requirement. Since successive frames have a much greater
difference at lower framerates, the bitrate requirements should be
comparable. Halving the framerate certainly does not reduce the
bitrate requirement by 50%. At best it reduces it by 20% or so.

Rich