Re: [Discuss-gnuradio] problem with audio extraction in NTSC

[Berndt Josef Wulf]

On Fri, 18 Feb 2005 04:57 am, Eric Blossom wrote:
> On Thu, Feb 17, 2005 at 05:37:47AM +0000, address@hidden wrote:
> > > Great.  I don't know anything about this package.  It would however be
> > > great it it worked with wxPython.  I'd hate to give up the cross
> > > platform portability.
> >
> > The package appears to be written mostly in Fortran.  I'm not sure
> > how cross platform that makes it.  Also, a quick test that I did
> > using dummy data (just plotting an array) was burning about 30% CPU
> > on my P4 2.4 at 10 frames per second.  I'll see if I can improve
> > this but initial results could look better...  If this doesn't work
> > out what other avenues should we consider?  What was the issue with
> > the old Qt versions?
>
> Qt is *not* free for either OS/X or Windows.
> As far as I know there is not a well developed set of bindings for use
> from Python.

This is not true. I've QT3 installed on both, WinXP and NetBSD. QT is 
available under various licenses. For non-commercial use you can use the 
non-commercial QT Edition.

The QT edition installed on my WinXP system shipped with the book that I 
purchased a little while ago:

Bruce Perens' Open Source Series
C++ GUI Programming with QT3
Jasmin Blanchette, Mark Summerfield
Prentice Hall
ISBN 0-13-324072-2

It comes with a CD containing a non-commercial version of QT3 for 
Unix/Linux/MacOS and Windows.

Python provides modules for QT3 bindings. I've since created my own version of 
wxgui using the pyqt package just for fun. And yes, I like QT3 and hence my 
opinions on this subject are biased... :-)
 
> The only real problem with wxPython as far as I can tell is the
> plotting speed.  We should keep our attention on this one problem and
> not jump ship.

I believe that GnuRadio and GUI development are two totally different issues 
and should be dealt with accordingly. Python provides the needed  cross 
platform compatibility, GUI development is a matter for application 
developers. I've recreated a couple of the GUI applications using QT3. I'm 
sure that there are many other GUI package that are more and less suitable 
for this purpose.

Having said this, I like to encourage the GnuRadio project in continuing their 
efforts in providing example designs using python and wxWindows to 
demonstrate the functionality and application of GnuRadio.

> First off we should determine *where* it's slow.  Is it the python code,
> or is it the c++ stuff?  There are at least two tools available to us:
> oprofile and the python profiler.  If it's in the python, again, let's
> measure.  If it's related to the use of numeric for some of the
> processing, we can easily move that into the C++ part of gnu radio.
>
> Worst case, we recode the wxgui/plot.py class into C++.  This should
> be pretty much of a mechanical translation.  I seriously doubt that
> the underlying wxWidgets line drawing code has any performance
> problem.
>
> Again, start with performance measurements, then go from there.


cheerio Berndt
-- 
Every man who says frankly and fully what he thinks is doing a public service.
[Leslie Stephen]