Painting Initial Frame

Bob (
Sat, 4 Nov 1995 18:50:35 -0600

<Windows 3.1 CuSeeMe 0.70b1 28.8 dialup>

I've noticed that on slow/busy reflectors, the "complete" frame often takes
a while to get painted completely. This is especially troublesome with the
initial CuSeeMe Logo, which often leaves incomplete portions behind which
distort the true image. I imagine this problem is minor on higher speed
lines or less busy reflectors. However, the "herd" is/will be 28.8.

Anyway, some thoughts...

It would seem that getting the total initial frame painted as quickly as
possible would reduce overall reflector traffic, since less time is then
wasted trying to clean up an original frame that has changed. Especially
with public reflectors that have a lot of come-and-go show/no-show traffic.

Suggestion: After a quick scan of the initial frame to be sent to a "new"
viewer, choose an initial solid frame which best matches the overall frame,
perhaps one of a palette of 16 white-grey intermediate-black solid frames,
and tell the viewer in a byte to display the chosen solid frame. Or, keep a
set of "intelligent" initial frames (light top, grey center, darker bottom;
etc.), and apply a filter to select the first receiver frame. If you want
to retain the CuSeeMe Logo, leave it there for 5 seconds or so, then replace
with the selected frame.

Since the relevant data will tend to be centered in the frame, methodically
paint the frame rectangularly from the center out. On the first pass, omit
sending initial squares which "closely" match the intial solid frame.
Consider halving or quartering the information in every 1st square sent, and
dither back at the receiver. They will be cleaned up later when the square
is sent again. Getting the initial image in some kind of "correct"
decipherable format is the primary concern. The brain will "clean it up",
in the sense that the image will be better defined and integratable earlier
than it is now. Keep track of where the face is (pattern recognition).
When behind in data transmission, put a priority on the facial squares.

Just some thoughts...