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

[Steven Friedrich]

I've noticed that several apps support images of the user, such as KMail, 
which supports a 40x40 pixel jpeg.

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.

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

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

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