How do I create a 40x40 pixel monochrome mage for KMail?

Polytropon freebsd at
Fri Jan 29 17:51:09 UTC 2010

On Fri, 29 Jan 2010 12:41:06 -0500, Steven Friedrich <freebsd at> wrote:
> I have a webcam, but it won't take  a monochrome picture and it doesn't 
> snapshot all the resolutions that it can display in. In particular, I tried 
> the two lowest and the lowest, sqcif, isn't supported by my webcam and qsif 
> seg faults. Those would have been 128x96 and 160x120.
> I figured that if I used the lowest resolution, I could crop out a 40x40 
> image.

You can use ImageMagick's convert command to scale the
image, and turn it into monochrome; see "man convert"
for -resize and -monochrome parameters. It's even possible
to use Gimp for this task. :-)

> Kopete also supports a 200x200 pixel image, but I think it requires exactly 
> 200x200, so 128x96 won't work.

You can use "!" with -resize to force a specific image
size, even if it violates the source picture's aspect
ratio (which -resize usually keeps).

> I thought that someone said they used kamera to take a snapshot with their 
> webcam but Logitech webcams aren't listed.

Maybe you can use gtkam / gphoto2 to talk to the Logitech
camera? I don't own one because I'm familiar with the fact
that they are not standard-compatible and that's why not

> I can take one with pwcview, which is what I was talking about above.

You can even use a "regular" digital camera to take the
photo, transfer it from the camera (or its CF or SD storage)
and then postprocess it with ImageMagick.

Magdeburg, Germany
Happy FreeBSD user since 4.0
Andra moi ennepe, Mousa, ...

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