forwarded message from Marcus O.C. Metzler

[Marcus O.C. Metzler <mocm@netcologne.de>]

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From: "Marcus O.C. Metzler" <mocm@netcologne.de>
To: Klaus Schmidinger <kls@cadsoft.de>
Subject: Re: Thoughts on VDR evolution - and gVideo
Date: Mon, 25 Sep 2000 17:57:56 +0200 (CEST)

Klaus Schmidinger writes:
 > On Mon, Sep 25, 2000 at 05:03:36PM +0200, Marcus O.C. Metzler wrote:
 > > Schuett Thomas writes:
 > >  > After all this big ideas I have a pretty simple one:
 > >  > 
 > >  > I would like to have gVideo splitted into
 > >  > - one app to bring a TV screen on the computer monitor
 > >  >   (without blocking /dev/video instream).
 > >  > - one app to show available channels and to switch the channel
 > >  > 
 > > This should be possible with the resource manager I am working on.
 > > I'd have to finish it first, though. After that I could work on it.
 > > 
 > > Marcus
 > 
 > Hi Marcus,
 > 
 > can you give us a brief description on how this resource manager
 > is going to work? Just a few hints to get the idea. Currently
 > a program that wants to read from /dev/video simply opens a file
 > on it and reads from it. What will have to be done different
 > when there is a resource manager?
 > 
The resource manager would provide clients (via Unix or TCP sockets)
with the opportunity to request io from its resources. Those resources
would be the devices of the DVB card (although it should be able to
handle other devices too). 
As a client you would say something like: "I require the output of
device /dev/video" and the resource manager would provide it, if
possible and the clients priority allows it. Via file descriptor
passing it would also be possible for clients on the same system to
get full control of a device. 
The first client of the resource manager would be the libdvb, so that
most of the stuff going on between the resource manager and the libdvb
would be hidden and the application would just use libdvb. 
At the moment I have realized io requests to certain devices and file
descriptor passing. Although, there is no priority or authentication
checking implemented yet. The next step would be to provide some
functions that give access to ioctl calls via the resource manager.
When I get stuff working well enough I will make a first release.

Since we are still working on other things, the resource manager has
not been a full time project, but I hope I will soon have more time to
work on it. I will also use the new API we are working on with Nokia,
which already allows separate access of the tuning front-end and the
v4l device that is concerned with the display. 
So the separation would already be possible by using the new API and
the drivers for that will come out before the resource manager.

Marcus

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Dr. Marcus Metzler                             
mocm@netcologne.de                     http://www.metzlerbros.de
mocm@convergence.de                    http://www.convergence.de

Convergence Integrated Media GmbH          
Rosenthaler Str. 51                   
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