toddb@jenzy.labs.tek.com (toddb) (05/07/91)
Due to a constant rate of requests for VEX, MVEX and DC&C papers and
code, I've placed everything available on export.lcs.mit.edu (18.30.0.238)
in contrib/vex/. for easy access. The files in this directory are
described below. Briefly, VEX is a Video Extension to X that I worked
on from June '88 to about September '90. It provides complete
abstractions within X for:
- video input (displaying a video stream in a drawable)
- video output (converting a drawable into a video stream)
- device control (for devices that produce/consume the video stream)
- connectivity (how the devices and video inputs/outputs are connected)
However, when proposed as an X Consortium Standard, the device control and
connectivity caused some members to gag: X extensions should only address
issues directly associated with the display. This means that VEX
is dead, dead, dead as a standard, but you can still get the sources
if you still need to get some work done.
Since then I wrote the documentation for two separate protocols:
- MVEX, or Minimal Video Extension to X, (or even, son of VEX), that
only addresses video input and video output. Essentially, it is
VEX without arms and legs... a quadruple amputee I guess.
- DC&C, or Device Control and Connectivity, is a non-X protocol
that provides device control and connectivity to any application;
i.e. it is window system independent.
Tektronix is strongly commited to its customers in the video broadcast
world, and for now I am continuing to work on MVEX and DC&C for use
in Tektronix products. Eventually, I'll post the sources for both MVEX
and DC&C, because Tek no longer has a workstation business and lacks vast
resources to push this as a standard. Hence, I'll leave proposing
MVEX as a consortium standard to future fans.
The files in this directory are:
vex-papers.tar.Z includes 3 published papers on VEX, the protocol doc,
the encoding doc and the vexlib doc.
VEX.tar.Z a fairly complete implementation of vex, including
server, vexlib and some sample user-level code.
DCandC.doc.tar.Z this is the protocol, the encoding and the library
documentation for DC&C, all rolled into one. It is
written as an API because its easier to understand
in that form.
MVEX.doc.6.0.tar.Z the MVEX protocol doc.
README this file
---------------
internet: toddb@sail.labs.tek.com c--Q Q
US: Todd Brunhoff; Video and Electronic Systems Lab; `
Tektronix, Inc.; Box 500 MS 50-321, Beaverton OR 97077 -
Phone: (503) 627-1121