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Date: 07 Sep 2006 14:05:49
From:
Subject: Program for getting line-outs from web cam images


Hello all,

I have tried searching the newsgroups for my question, with no luck.
Though that certainly doesn't mean I didn't miss something. At my old
lab we had a frame grabber card that allowed us to make contour plots
of an image from a ccd camera. I would like to do something similar at
my new job for a demonstration and later for actual use. What we have
are some very nice web cams (Toucam II and StellaCam-EX) that I am
trying to use to image the focus of a HeNe laser. I have LabView
programs that will take a line-out along the x- and y-axis of the image
and fit that to a Gaussian. This is very useful when determining how
well a laser focuses. I am including the astronomy groups, because you
guys play with these cameras all of the time and I'm sure someone
needed to do something similar, like taking an image of a star to see
how well their telescope focuses.

Ultimately my problem is that the software that comes with both cameras
does not allow me to save in the format that I need and I was wondering
if there is software (freeware, shareware) that will alow me to save in
the needed format.

Thanks for the help

Kevin





 
Date: 07 Sep 2006 20:02:14
From:
Subject: Re: Program for getting line-outs from web cam images


I don't know if this will help, but here is a link to a free image
processing software package intended for robot imaging. It will work
with most USB based web cams, but I am not certain of the exact
software interface.

http://www.roborealm.com/

Joe Dunfee



 
Date: 07 Sep 2006 15:45:07
From: STEVE ROBERTS
Subject: Re: Program for getting line-outs from web cam images



Nicholas Sherlock wrote:
> kdschultz@gmail.com wrote:
> > Ultimately my problem is that the software that comes with both cameras
> > does not allow me to save in the format that I need and I was wondering
> > if there is software (freeware, shareware) that will alow me to save in
> > the needed format.

try ImageJ, its freeware, science oriented, and has a twain
interface.

Steve Roberts



 
Date: 08 Sep 2006 10:14:31
From: Nicholas Sherlock
Subject: Re: Program for getting line-outs from web cam images


kdschultz@gmail.com wrote:
> Ultimately my problem is that the software that comes with both cameras
> does not allow me to save in the format that I need and I was wondering
> if there is software (freeware, shareware) that will alow me to save in
> the needed format.

Open, these cameras will support a TWAIN interface, and pictures can be
captured by any program which can use TWAIN. I'm interested, though:
Which formats do your capture programs save in that you can't use?

Cheers,
Nicholas Sherlock

--
http://www.sherlocksoftware.org


 
Date: 08 Sep 2006 09:09:45
From:
Subject: Re: Program for getting line-outs from web cam images


My apologies. What is clear in my head is not always clear on paper!
Ultimately a text file with columnsxrows=total pixels and each entry
being the "intensity" on that particular camera pixel.

Thanks everyone for the other answers despit my lack of clarity.

Kevin

Carsten A. Arnholm wrote:
> kdschultz@gmail.com wrote:
> > Hello all,
> >
> > I have tried searching the newsgroups for my question, with no luck.
> > Though that certainly doesn't mean I didn't miss something. At my old
> > lab we had a frame grabber card that allowed us to make contour plots
> > of an image from a ccd camera. I would like to do something similar at
> > my new job for a demonstration and later for actual use. What we have
> > are some very nice web cams (Toucam II and StellaCam-EX) that I am
> > trying to use to image the focus of a HeNe laser. I have LabView
> > programs that will take a line-out along the x- and y-axis of the
> > image and fit that to a Gaussian. This is very useful when
> > determining how well a laser focuses. I am including the astronomy
> > groups, because you guys play with these cameras all of the time and
> > I'm sure someone needed to do something similar, like taking an image
> > of a star to see how well their telescope focuses.
> >
> > Ultimately my problem is that the software that comes with both
> > cameras does not allow me to save in the format that I need
>
> Which is ....?
>
> > and I was
> > wondering if there is software (freeware, shareware) that will alow
> > me to save in the needed format.
>
> There is no way to answer the question since "the format you need" is
> unknown....
>
> --
> Carsten A. Arnholm
> http://arnholm.org/
> N59.776 E10.457



  
Date: 08 Sep 2006 22:55:34
From: Carsten A. Arnholm
Subject: Re: Program for getting line-outs from web cam images


kdschultz@gmail.com wrote:
> My apologies. What is clear in my head is not always clear on paper!
> Ultimately a text file with columnsxrows=total pixels and each entry
> being the "intensity" on that particular camera pixel.

That is a very generic description that would suit almost any image file
format on the planet.

Webcams deliver 8bit AVI files, encoded using a codec depending in the
camera in question. Lots of programs can extract the AVI frames to BMP for
example.

FITS files would perhaps suit your needs more directly, but there are also
many variants of FITS files.

You also have to take into account that webcams are typically equipped with
a colour chip. This also influences the file format. You get 3 intensities
per image pixel after debayering.

Clear skies
Carsten A. Arnholm
http://arnholm.org/
N59.776 E10.457



   
Date: 08 Sep 2006 20:32:04
From: Brian Tung
Subject: Re: Program for getting line-outs from web cam images


kdschultz@gmail.com wrote:
> My apologies. What is clear in my head is not always clear on paper!
> Ultimately a text file with columnsxrows=total pixels and each entry
> being the "intensity" on that particular camera pixel.

Carsten A. Arnholm wrote:
> That is a very generic description that would suit almost any image file
> format on the planet.

I don't think so. By text is surely meant something like ASCII. Under
that interpretation, something like plain-text PPM, PGM, or PBM would be
acceptable; possibly something like XPM or XBM would work, too. But not
GIF or JPEG or PNG.

There are image file converters available that will convert any of the
image file formats to PPM, which can then be manipulated quantitatively
by a simple script.

--
Brian Tung <brian@isi.edu >
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html


    
Date: 09 Sep 2006 19:16:13
From: Carsten A. Arnholm
Subject: Re: Program for getting line-outs from web cam images


Brian Tung wrote:
> kdschultz@gmail.com wrote:
>> My apologies. What is clear in my head is not always clear on paper!
>> Ultimately a text file with columnsxrows=total pixels and each entry
>> being the "intensity" on that particular camera pixel.
>
> Carsten A. Arnholm wrote:
>> That is a very generic description that would suit almost any image
>> file format on the planet.
>
> I don't think so. By text is surely meant something like ASCII.
> Under that interpretation, something like plain-text PPM, PGM, or PBM
> would be acceptable; possibly something like XPM or XBM would work,
> too. But not GIF or JPEG or PNG.
>
> There are image file converters available that will convert any of the
> image file formats to PPM, which can then be manipulated
> quantitatively by a simple script.

You are right. I missed the "text" part and focused on the
"columnsxrows=total pixels".

But for image processing I would still suggest using something like Fits as
the starting point instead. It is more compact, more efficient, can provide
more precision and there is free programming tools for it (e.g. CFITSIO).

Clear skies
Carsten A. Arnholm
http://arnholm.org/
N59.776 E10.457



 
Date: 08 Sep 2006 08:20:51
From:
Subject: Re: Program for getting line-outs from web cam images


Joe is correct. You should be able to save a webcam image in a variety
of formats using RoboRealm. You may also be interested in the focus
module at http://www.roborealm.com/help/focus.php which was built to
help one improve the focus of an image that may act similar to the
LabView procedure.

STeven.
www.roborealm.com



 
Date: 08 Sep 2006 15:42:41
From: Carsten A. Arnholm
Subject: Re: Program for getting line-outs from web cam images


kdschultz@gmail.com wrote:
> Hello all,
>
> I have tried searching the newsgroups for my question, with no luck.
> Though that certainly doesn't mean I didn't miss something. At my old
> lab we had a frame grabber card that allowed us to make contour plots
> of an image from a ccd camera. I would like to do something similar at
> my new job for a demonstration and later for actual use. What we have
> are some very nice web cams (Toucam II and StellaCam-EX) that I am
> trying to use to image the focus of a HeNe laser. I have LabView
> programs that will take a line-out along the x- and y-axis of the
> image and fit that to a Gaussian. This is very useful when
> determining how well a laser focuses. I am including the astronomy
> groups, because you guys play with these cameras all of the time and
> I'm sure someone needed to do something similar, like taking an image
> of a star to see how well their telescope focuses.
>
> Ultimately my problem is that the software that comes with both
> cameras does not allow me to save in the format that I need

Which is ....?

> and I was
> wondering if there is software (freeware, shareware) that will alow
> me to save in the needed format.

There is no way to answer the question since "the format you need" is
unknown....

--
Carsten A. Arnholm
http://arnholm.org/
N59.776 E10.457




 
Date: 12 Sep 2006 18:03:37
From: Karsten Schulz
Subject: Re: Program for getting line-outs from web cam images


hi,

u can try my software to gain contours or other
characters www.kahnsoft.de.vu

greetings
Karsten Schulz

<kdschultz@gmail.com > schrieb im Newsbeitrag
news:1157663149.068268.73980@b28g2000cwb.googlegroups.com...
> Hello all,
>
> I have tried searching the newsgroups for my question, with no luck.
> Though that certainly doesn't mean I didn't miss something. At my old
> lab we had a frame grabber card that allowed us to make contour plots
> of an image from a ccd camera. I would like to do something similar at
> my new job for a demonstration and later for actual use. What we have
> are some very nice web cams (Toucam II and StellaCam-EX) that I am
> trying to use to image the focus of a HeNe laser. I have LabView
> programs that will take a line-out along the x- and y-axis of the image
> and fit that to a Gaussian. This is very useful when determining how
> well a laser focuses. I am including the astronomy groups, because you
> guys play with these cameras all of the time and I'm sure someone
> needed to do something similar, like taking an image of a star to see
> how well their telescope focuses.
>
> Ultimately my problem is that the software that comes with both cameras
> does not allow me to save in the format that I need and I was wondering
> if there is software (freeware, shareware) that will alow me to save in
> the needed format.
>
> Thanks for the help
>
> Kevin
>