MATLAB Central Newsreader - Image Acquisition - preview "dark window"

Image Acquisition - preview "dark window"

N N — Thu, 31 Jan 2008 07:03:07 -0500

Hi,

I have matlab R2007a with image acquisition toolbox. I
recently have connected a scientific camera (pixelink,
PLA641)to my Win XP laptop. Two other cameras that I've
tried are working fine.

Issue is.........although matlab recognises the camera as
a "winvideo" device, when I 'preview/start video input'
the screen appears "DARK". When I preview through the
vendor's software, I have no problems.
Comments/suggestions are much appreciated.

NB: I do have two observations
1. In matlab, the camera's supported video format seems
slightly different (more!) than what is provided by vendor
(1280x1024 versus 1288 x 1032, respectively).
2. Occasionally (~1% of time) I do see a still picture in
the preview window(highly inconsistent though).

Than Q!

Re: Image Acquisition - preview "dark window"

Mark Jones — Thu, 31 Jan 2008 14:30:07 -0500

N N wrote:
> Hi,
>
> I have matlab R2007a with image acquisition toolbox. I
> recently have connected a scientific camera (pixelink,
> PLA641)to my Win XP laptop. Two other cameras that I've
> tried are working fine.
>
> Issue is.........although matlab recognises the camera as
> a "winvideo" device, when I 'preview/start video input'
> the screen appears "DARK". When I preview through the
> vendor's software, I have no problems.
> Comments/suggestions are much appreciated.
>
> NB: I do have two observations
> 1. In matlab, the camera's supported video format seems
> slightly different (more!) than what is provided by vendor
> (1280x1024 versus 1288 x 1032, respectively).
> 2. Occasionally (~1% of time) I do see a still picture in
> the preview window(highly inconsistent though).
>
> Than Q!

Hi,

This camera is a IEEE 1394 FireWire camera, have you tried using the CMU
DCAM driver with it?

You might have better results with it:

http://www.mathworks.com/products/imaq/supportedio13864.html

You can find the correct driver version in:
matlab\toolbox\imaq\imaqextern\drivers\win32

Mark

Re: Image Acquisition - preview

N N — Thu, 31 Jan 2008 22:57:01 -0500

Thanks, Mark. I did try CMU's DCAM driver but to no avail.
I forgot to mention it in my earlier email.

Thanks again and best regards!

Mark Jones <mark.jones@mathworks.com> wrote in message

<47A1DB6F.3090109@mathworks.com>...
> > Hi,
>
> This camera is a IEEE 1394 FireWire camera, have you
tried using the CMU
> DCAM driver with it?
>
> You might have better results with it:
>
>
http://www.mathworks.com/products/imaq/supportedio13864.htm
l
>
> You can find the correct driver version in:
> matlab\toolbox\imaq\imaqextern\drivers\win32
>
> Mark

Re: Image Acquisition - preview

Mark Jones — Thu, 07 Feb 2008 16:33:23 -0500

When you say that you tried CMU's DCAM to no avail, specifically what do
you mean? Did it fail to work with the CMU demo program or just with
MATLAB. Also, what version of the CMU drivers were you using? It is
possible that the camera is not DCAM compliant.

However, when using the WDM or VFW drivers, how did the image look using
the AMCAP utility?
http://www.mathworks.com/products/imaq/supportedio13875.html

Also, what is the output that that you see if you create the winvideo
object and then do the following:

% modify the line below as needed for your desired format and device
vid=videoinput('winvideo')
% and then...
start(vid);
d=getdata(vid);
f10=d(:,:,:,10);
max(max(f10))
min(min(f10))

Can you send me the answers to the above questions as well as the output
of the above commands? It would also be good to see the output from the
IMAQSUPPORT command.

Thank you,
Mark

N N wrote:
> Thanks, Mark. I did try CMU's DCAM driver but to no avail.
> I forgot to mention it in my earlier email.
>
> Thanks again and best regards!
>
>
>
>
> Mark Jones <mark.jones@mathworks.com> wrote in message
>
>
>
>
> <47A1DB6F.3090109@mathworks.com>...
>>> Hi,
>> This camera is a IEEE 1394 FireWire camera, have you
> tried using the CMU
>> DCAM driver with it?
>>
>> You might have better results with it:
>>
>>
> http://www.mathworks.com/products/imaq/supportedio13864.htm
> l
>> You can find the correct driver version in:
>> matlab\toolbox\imaq\imaqextern\drivers\win32
>>
>> Mark
>