[Xorg] Implementing "Xv" extension on DDX which don'tsupportit in hardware...

Alan Cox alan at lxorguk.ukuu.org.uk
Mon Jul 12 05:16:54 PDT 2004

On Sul, 2004-07-11 at 21:42, Roland Mainz wrote:
> Depends... server-side image scaling is usually faster than client-side
> (assuming you make the images larger :) because you transfer _less_
> data. Much less...

It isnt that simple because in many cases the scaling and decoding
can be a single pass more efficiently. Its hard to gauge without someone
putting a really good scaler in X (not the X image extension stuff!)

If you have the time to try that experiment I'd be interested in the
results, although for modern hardware I suspect that the DRI layer or
OpenGL textures may be the way to go since that gives you access to
hardware scaling and format conversion

> If - and only "if" - MITSHM is available and suitable for the
> application. MITSHM itself is a PAIN on some OSes since the number and
> size of the shared segments is _limited_. IMHO MITSHM should go away,
> replaced by a shared memory X transport...

Heres $2 kid get yourself a real OS ;)

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