Hi all,

I've been successful in running ARToolKit on my
Macintosh G4. I've instrumented simpleTest with
some code to measure the time it takes for
DecompressSequenceFrameS to execute and found
out that it alternates between 13 and 49
milliseconds with my 500 MHz machine. Any
ideas as to what's really going on?

Thanks,

-Barry
-- 
Barry J. Menich
Member of Technical Staff
Science Advisory Board Associate
Motorola Labs
Email = cemx61@e ............
Phone = (847) 632-3106
Cell =  (847) 452-1372
Fax  =  (847) XXX-XXXX
1-800-SKYPAGE (PIN# 1131695)
"Think for yourself and question all authority."
- Arthur C. Clark
"Failure is often the result of failing to fail."
- Jordan Ayan
 

Barry J. Menich (cemx61@e ............) wrote:

> I've been successful in running ARToolKit on my Macintosh G4.

I've been working w/ it on my G4 as well, but I've been having a lot
of problems.

Could you detail your setup?

-- 
Ryan Singer :: http://feltpresence.com

"There is no defense, except stupidity, against the impact
 of a new idea."
   - P.W. Bridgeman

My guess is this.   It is taking at least 13 ms to return a frame, and 
at 30 fps, the frames come in about every 33ms.  Two frames take 66ms, 
and 13+49 is 62;  assuming it is only taking a few milliseconds to do 
the rest of the work your program is doing each from, you must be 
coming in the second time before a frame arrives and waiting.  Are you 
running at 30fps capture rate?

Of course, the same argument would apply if you were running slower and 
dropping frames;  you might be just missing a frame and waiting.

On Wednesday, November 13, 2002, at 10:00 AM, Barry J. Menich wrote:

> Hi all,
>
> I've been successful in running ARToolKit on my
> Macintosh G4. I've instrumented simpleTest with
> some code to measure the time it takes for
> DecompressSequenceFrameS to execute and found
> out that it alternates between 13 and 49
> milliseconds with my 500 MHz machine. Any
> ideas as to what's really going on?
>
> Thanks,
>
> -Barry
> -- 
> Barry J. Menich
> Member of Technical Staff
> Science Advisory Board Associate
> Motorola Labs
> Email = cemx61@e ............
> Phone = (847) 632-3106
> Cell =  (847) 452-1372
> Fax  =  (847) XXX-XXXX
> 1-800-SKYPAGE (PIN# 1131695)
> "Think for yourself and question all authority."
> - Arthur C. Clark
> "Failure is often the result of failing to fail."
> - Jordan Ayan

 

Also to make things worse I imagine that there would be operating system
scheduling and timing issues as well. Your ARToolKit process is competing
against other processes and if they get switched in and out, then this will
add further delay. Also, the resolution of the timer might not be that good
either, and so it rounds it to the nearest N milliseconds.

regards,
Wayne

----- Original Message -----
From: "Blair MacIntyre" <blair@c ............>
To: <cemx61@e ............>
Cc: <artoolkit@h ..................>
Sent: Thursday, November 14, 2002 2:16 AM
Subject: Re: Macintosh Question


> My guess is this.   It is taking at least 13 ms to return a frame, and
> at 30 fps, the frames come in about every 33ms.  Two frames take 66ms,
> and 13+49 is 62;  assuming it is only taking a few milliseconds to do
> the rest of the work your program is doing each from, you must be
> coming in the second time before a frame arrives and waiting.  Are you
> running at 30fps capture rate?
>
> Of course, the same argument would apply if you were running slower and
> dropping frames;  you might be just missing a frame and waiting.
>
> On Wednesday, November 13, 2002, at 10:00 AM, Barry J. Menich wrote:
>
> > Hi all,
> >
> > I've been successful in running ARToolKit on my
> > Macintosh G4. I've instrumented simpleTest with
> > some code to measure the time it takes for
> > DecompressSequenceFrameS to execute and found
> > out that it alternates between 13 and 49
> > milliseconds with my 500 MHz machine. Any
> > ideas as to what's really going on?
> >
> > Thanks,
> >
> > -Barry
> > --
> > Barry J. Menich
> > Member of Technical Staff
> > Science Advisory Board Associate
> > Motorola Labs
> > Email = cemx61@e ............
> > Phone = (847) 632-3106
> > Cell =  (847) 452-1372
> > Fax  =  (847) XXX-XXXX
> > 1-800-SKYPAGE (PIN# 1131695)
> > "Think for yourself and question all authority."
> > - Arthur C. Clark
> > "Failure is often the result of failing to fail."
> > - Jordan Ayan
>