LZMA compression

[Matt Campbell]

Alex Pelts wrote:
> Does vnc accumulate dictionary between frame updates?

I was referring to the dictionary maintained by the LZMA codec, if VNC 
were to use LZMA compression.  I noticed that in the ZRLE encoding, a 
single zlib stream is maintained for the whole session.  I presume the 
same thing could be done with LZMA; in that case, the LZMA codec would 
maintain a dictionary for the duration of the session.

> Also things vnc compresses are mostly flat color surfaces which compress 
> well with most any method.

What about rendered text and multi-colored desktop backgrounds such as 
the ever-popular "Bliss" background under Windows XP?

> I found most slowness during vnc session on windows comes not from the 
> bandwidth but from screen polling. This problem is eliminated with EE or 
> PE of the vnc with mirror driver.

What display functionality, if any, does the system disable while the 
VNC mirror driver is active?

Matt