Hi

I didn' change anything at the function arVideoGetImage.
So the Code is the same as you can download it from the page of =
ARToolKit.
I just copies it from the simple project into my OpenSG project.
The call of this function:

if( (dataPtr =3D (ARUint8 *)arVideoGetImage()) =3D=3D NULL ) {
arUtilSleep(2);
printf("VideoBild wurde nicht
gelesen!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
exit (0);
}

As you can see the same ar in simple.

But not the same result ;-)

Bye Manuel

-----Urspr=FCngliche Nachricht-----
Von: Daniel Wagner [mailto:daniel@i ...............]=20
Gesendet: Sonntag, 5. Dezember 2004 14:45
An: Manuel B=FCchler
Cc: artoolkit@h ..................
Betreff: Re: arVideoGetImage

Manuel B=FCchler wrote:

> I=92m working on an combination of ARToolKit and OpenSG.
>
> My first try is to combine the 01hello project with the simple project =

> of ARtoolKit.
>
> My problem is that the function arVideoGetImage work perfect in the=20
> simple project of ARToolKit.
>
> But when I put it into my own OpenSG project (used in the same way as=20
> in the simple project) the result of
>
> The call of this function is NULL. So the hole application stops.
>
hi Manuel,

both libraries are open source.
it should be no problem for you to step into arVideoGetImage and provide =

the community here with more information about where the malfunction=20
happens...

bye,
Daniel

Hello

Here i get you a more specific explanation what is my problem. I made =
all of
these init-stuff which Is also in the example project simple. Now I want =
to
get an image from my camera with this code (the same as in simple except =
the
printf)

if( (dataPtr =3D (ARUint8 *)arVideoGetImage()) =3D=3D NULL ) {
        arUtilSleep(2);
		printf("Videobild w=FCrde nicht
geladen!!!!!!!!!!!!!!!!!!!!!!!");
        exit(1);
    }

But everytime the programm stops with exit(1) because the dataPtr is =
NULL
I tried to find the error in the libARvideo. I made some printf to get =
to
know where the error begins in the function arVideoGetImage.
But this function seem to be ignored. Every printf I made in this =
function
don't come to the console. So it seem to be that this function isn't =
call.
But there is a call as you can see in the code above.

Does anyone know about this error and can help me to solve it?

Thanks.

-----Urspr=FCngliche Nachricht-----
Von: owner-artoolkit@h ..................
[mailto:owner-artoolkit@h ..................] Im Auftrag von Peter Oost
Gesendet: Sonntag, 5. Dezember 2004 22:52
An: artoolkit@h ..................
Betreff: Re: arVideoGetImage

> Manuel B=FCchler wrote:
> both libraries are open source.
> it should be no problem for you to step into arVideoGetImage and
> provide the community here with more information about where the
> malfunction happens...
>
> bye,
> Daniel

"Manuel B=FCchler" wrote:
> Hi
>
> I didn' change anything at the function arVideoGetImage.
> So the Code is the same as you can download it from the page of
> ARToolKit. I just copies it from the simple project into my OpenSG
> project.
> The call of this function:
>
> if( (dataPtr =3D (ARUint8 *)arVideoGetImage()) =3D=3D NULL ) {
> arUtilSleep(2);
> printf("VideoBild wurde nicht
> gelesen!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
> exit (0);
> }

Before you can call arVideoGetImage() you'll have to initialize a few=20
things. Check whether you have done this properly (see the init() =
function=20
in the Simple example). Also look inside the arVideoGetImage function to =
see

where exactly it goes wrong (as Daniel suggested).

-Peter=20

On Wed, 2004-12-08 at 21:22 +0100, Manuel Büchler wrote:
> Hello
> 
> Here i get you a more specific explanation what is my problem. I made all of
> these init-stuff which Is also in the example project simple. Now I want to
> get an image from my camera with this code (the same as in simple except the
> printf)
> 
> if( (dataPtr = (ARUint8 *)arVideoGetImage()) == NULL ) {
>         arUtilSleep(2);
> 		printf("Videobild würde nicht
> geladen!!!!!!!!!!!!!!!!!!!!!!!");
>         exit(1);
>     }
> 
> But everytime the programm stops with exit(1) because the dataPtr is NULL
> I tried to find the error in the libARvideo. I made some printf to get to
> know where the error begins in the function arVideoGetImage.
> But this function seem to be ignored. Every printf I made in this function
> don't come to the console. So it seem to be that this function isn't call.
> But there is a call as you can see in the code above.

The first thing to spring to mind is: did you put the printf in the
correct arVideoGetImage function? There are different function
definitions for V4L, firewire cams, win32 etc.
Other than that I wouldn't know how to help you.

-Peter

On Wed, 2004-12-08 at 21:22 +0100, Manuel Büchler wrote:
> Hello
> 
> Here i get you a more specific explanation what is my problem. I made all of
> these init-stuff which Is also in the example project simple. Now I want to
> get an image from my camera with this code (the same as in simple except the
> printf)
> 
> if( (dataPtr = (ARUint8 *)arVideoGetImage()) == NULL ) {
>         arUtilSleep(2);
> 		printf("Videobild würde nicht
> geladen!!!!!!!!!!!!!!!!!!!!!!!");
>         exit(1);
>     }
> 
> But everytime the programm stops with exit(1) because the dataPtr is NULL
> I tried to find the error in the libARvideo. I made some printf to get to
> know where the error begins in the function arVideoGetImage.
> But this function seem to be ignored. Every printf I made in this function
> don't come to the console. So it seem to be that this function isn't call.
> But there is a call as you can see in the code above.

Ah, I had a look at my own code, it uses this:

while( (dataPtr = (ARUint8 *)arVideoGetImage()) == NULL )
arUtilSleep(2);

Apparently it is quite likely that the first (few) calls don't
immediately give a correct result.

I hope this works for you.

-Peter

Manuel,

Getting NULL returned from arVideoGetImage is not cause for calling 
exit(), so don't do that.

NULL can be returned when a frame is not ready from the camera, but 
that doesn't mean one won't ever become ready. You should just keep 
sleeping and calling arVideoGetImage until either you get a frame or 
you reach some self-imposed time limit e.g. 10 seconds.

Regards,
Phil.

At 9:22 PM +0100 8/12/04, Manuel Büchler wrote:
>Hello
>
>Here i get you a more specific explanation what is my problem. I made all of
>these init-stuff which Is also in the example project simple. Now I want to
>get an image from my camera with this code (the same as in simple except the
>printf)
>
>if( (dataPtr = (ARUint8 *)arVideoGetImage()) == NULL ) {
>         arUtilSleep(2);
>		printf("Videobild würde nicht
>geladen!!!!!!!!!!!!!!!!!!!!!!!");
>         exit(1);
>     }
>
>But everytime the programm stops with exit(1) because the dataPtr is NULL
>I tried to find the error in the libARvideo. I made some printf to get to
>know where the error begins in the function arVideoGetImage.
>But this function seem to be ignored. Every printf I made in this function
>don't come to the console. So it seem to be that this function isn't call.
>But there is a call as you can see in the code above.
>
>Does anyone know about this error and can help me to solve it?
>
>Thanks.
>