OK, though I suspect many plugin writers would like to avoid all the extra
complexity, so perhaps the interface needs a render context hints object.

On 23/01/2008, Herman Robak <[EMAIL PROTECTED]> wrote:
>
> On Wed, 23 Jan 2008 11:58:27 +0100, Christian Thaeter <[EMAIL PROTECTED]>
> wrote:
>
> > Have a scheduler where we can assert frame pulls "I need frame 2 at
> > quality level N in 17ms, and btw i am playing forward, if possible
> > prepare me frame 2 and following as well". This Scheduler can the report
> > immediately "Yes sounds doable" or "No way, I wont even try, drop this".
> > As well as some extra hints like "give me the nearest frame to frame 40
> > within X ms" or adaptive quality/resolution while scrubbing one sees low
> > res/low quality preview and when stopping scrubbing the exact frame
> > where it stopped is rendered in (maybe incremental) better quality/res.
>
>   I'll elaborate a little on this one.  One of the ideas we (Christian,
> Richard and I) considered was "give me any of frame 30 to 50 within 17
> ms".
> That is, specify an acceptable range.  I will explain to everyone why this
> is useful.
>
>   If you seek through half an hour of video really quickly, by dragging
> the slider through the video in twenty-thirty seconds, it will play back
> blindingly fast: 50-100 times normal speed.  Every two seconds of video
> will be displayed as a single frame.  A five second clip will be on the
> screen less than 1/10 of a second.  Yet this brief flash is long enough
> that you notice it, if you know what you are looking for.
>
>   I've tried this in Cinelerra with large DV files.  It was smooth and
> responsive.  It was useful.  I loved it.
>
>   Now try this with high definition video, which is temporally compressed.
> It doesn't work.  You'll only get a few frames per second at best.
> Scrubbing and seeking gets at least ten times slower, unresponsive,
> laggy, jerky.  It was not very useful.  I hated it.
>
>
>   When you zip through a video at 100x speed, you won't care if it was
> frame 110 or frame 112 that just flashed by.  Because your "temporal
> resolution" has been "zoomed out" to one frame every fourth second.
> If Cinelerra displayed frame 135 instead of frame 110 you could not
> possibly tell, because at 100x speed it's just 1/100 second "wrong".
>
>   So playback at 10x speed or more should be quite easy, since the
> tolerance is so much wider.  But in order to exploit that, the backend
> must be told what the tolerence (the range) is.
>
> --
> Herman Robak
>
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>



-- 
Regards,
Martin
([EMAIL PROTECTED])
IT: http://methodsupport.com Personal: http://thereisnoend.org

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