Re: [GnomeMeeting-list] [PATCH] Better integration with Video4Linux for PWLIB

[Derek Smithies <derek indranet co nz>]

Hi,
 Nemosoft - after sending that rant,  I thought, oops - most unwise.

I am sorry about the rant - there are all sorts of implications etc in it 
that I don't want to make. 
 Some of the points in the rant are verifiable - 
    one can point to varous supporting emails to lists.
 some points in the rant are not easy to defend.
    attempting to defend those points would consume time in 
    numerous emails. 

I apologise for the rant - and hope we can put it behind us, and move on.

Let us move forward, and strive to reach the point of good code.

I am going to put an end to this discussion now (as far as I am 
concerned).


After watching pwlib in use for 4 years, there is one area of 
pwlib-vide4linux that is not compliant 
   pwlib-video4linux requires the driver to supply double buffered
   m  mapped video.  The spec says single buffered is OK.

Some have argued other aspects (eg size) but these have not been 
substantiated.


I want to put my time into fruitful discussions, honest discussions, 
clearly explained discussions that generate good working code.


I will not argue the letter below - that is pointless - we end up in the
situation of "consuming time in numerous emails".

Derek.


On Wed, 24 Sep 2003, Nemosoft Unv. wrote:

> Greetings,
> 
> On Tuesday 23 September 2003 00:17, Derek Smithies wrote:
> 
> I'll be short on this one.
> > ============================================
> >
> > <rant>
> >  One of the goals of linux people the world over is to replace MS with
> > Linux. This is fine. Consequently, for linux to be usable by the masses,
> > things like cameras, programs, drivers etc have to be installed simply.
> > No requirements for fiddling around with new kernels, editing conf files,
> > building from source.
> >
> > It should be
> >    rpm -Uvh gnomemeeting.rpm
> >    gnomemeeting
> >
> > Now, cameras (usb ones in particular) are easy to install. Just plug it
> > in. Non usb camera may require a grabber card.
> >
> > You see - just plug it in and it goes. This is what the Microsoft
> > interface is aiming for.
> >
> > In the four years that I have been involved in openh323, reading the
> > list, helping people,
> > my view is the biggest pain in the ass is camera and sound.
> >
> > Buggy drivers, (drivers that fail to meet the spec)
> > Authors who say, my driver meets the spec - it works with xawtv.
> > This is  a stupid and obnoxious comment.
> >
> >
> > STOP the crap software. fix the driver. make the driver meet the spec.
> > work harder. get it right.
> 
> Upon reading this rant, I decided to stop following this discussion. 
> Furthermore, I'm not going to help anyone anymore with Gnomemeeting 
> problems. 
> 
> First off: the PWC drivers work excellent with a lot of software; not just 
> xawtv or another single tool. The PWC driver meets the "spec", as far as 
> that means anything because the document is sometimes vague, and 
> incomplete. I even daresay PWC behaves a lot better than other webcam 
> drivers.
> 
> I content I may have accidently broken something in recent PWC version. 
> Fine, it happens, I know. No problem, we'll fix it. But for that, I need 
> your help! Linux is all about open source. So in case something breaks, you 
> can have a look yourself and see where I'm going wrong. But no, all I get 
> are messages like: "hey, the size your PWC returns is wrong , NOW FIX IT!". 
> Sorry, I don't respond very well to that.
> 
> >
> > openh323 is criticised because it does not work. Why does openh323 not
> > work? Cause the driver writer did not do his/her job correctly.
> >
> > I don't want to know about adding extra options to conf files. The
> > default option should always work.
> >
> > If linux video and sound drivers cannot work "out of the box", then there
> > is no hope of overtaking microsoft.
> 
> I have obsolutely no interest in taking over Microsoft. Sorry, this anit-MS 
> attitude I find highly annoying.
> 
> >
> > Yes, I know that microsoft code has many drivers that "don't work right".
> > That is no excuse.
> > The goal for linux is for all drivers to work.
> > If we can achieve that goal, linux has a chance.
> >
> > </rant>
> >
> >
> > Derek.
> >
> > P.S. sorry for venting/ranting, but I am sick of substandard driver code.
> >     it wastes so much developer time, getting applications to work with
> >      buggy drivers.
> 
> Thanks, you've just labeled 3 years of quite dedicated work as 
> "substandard". 
> 
> >
> >  On Mon, 22 Sep 2003, Nemosoft Unv. wrote:
> > > Hello,
> > >
> > > On Monday 22 September 2003 00:02, Derek Smithies wrote:
> > > > Chris,
> > > >  Modifying kernel code, or adding module parameters, are a pain.
> > >
> > > Not really. You can always send a patch to the apropriate maintainer
> > > (that would be me :))) It will then eventually percolate into kernels
> > > on user's systems. The most important thing is not to break (too many)
> > > existing applications.
> > >
> > > [...]
> > >
> > > >  You see, it means that anyone else who uses the QuickCam has to do
> > > > the same.
> > > >
> > > > Your patch is "fine", in that it works.
> > > > However, I really really don't want to add it, cause that will change
> > > > the operation of the pwlib v4l code for all cameras.
> > > >
> > > > Can I suggest that you modify your patch, so that it uses the hint
> > > > table, line 200 of video4linux.cxx
> > > > Modify the hint table so it includes a section for your QuickCam
> > > > camera. and put a new hint in the hint table.
> > > >
> > > > The new hint is
> > > >     HINT_USE_CURRENT_HARDWARE_SIZE 0x0400
> > > >
> > > > Then,  you have in your changes.
> > > > if (HINT (HINT_USE_CURRENT_HARDWARE_SIZE)) {
> > > >    your code;
> > > >  } else {
> > > >     previous code;
> > > >  }
> > > >
> > > >
> > > > Thus, if the camera is QuickCam, it uses your code.
> > > >      if the camera is anything else, nothing changes.
> > >
> > > If I may? First off, I think it's a bad idea to put too much camera
> > > specific code in your program. Second, if you do it, try to do it in
> > > the most general way possible. The QuickCam is using my PWC driver, and
> > > although I admit that driver is slightly "broken" in this case, your
> > > code should then work on all PWC supported cams, since they all suffer
> > > from the same problem, in which case I'm happy to point you to my API
> > > document on http://www.smcc.demon.nl/webcam/api.html which includes a
> > > PWC detection routine.
> > >
> > >  - Nemosoft
> 
> 

-- 
Derek Smithies Ph.D.                           This PC runs pine on linux for email
IndraNet Technologies Ltd.                     If you find a virus apparently from me, it has
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