piclist 2009\01\31\134613a >
Thread: Whiteboard image extraction
face BY : Vitaliy email (remove spam text)

"Olin Lathrop" wrote:
> Philip Pemberton wrote:
>> Speaking of whiteboard image extraction.. I've been (slowly) hacking
>> away at a program that takes a JPEG file containing a photo of a
>> whiteboard, removes the brightness variations caused by light shining
>> on it, makes the background pure white, and enhances the contrast so
>> you can see the text properly.
> I've captured whiteboard images a number of times with great success using
> two pictures.  Set the camera on a tripod, take the first picture, erase
> the
> board, then take the second picture with the same lighting and the camera
> in
> the same position.  A little image subtraction and scaling with existing
> image manipulation programs and you get a very nice copy of the whiteboard
> scribbles.

We don't have room for a tripod in the conference room, and it is just more
convenient to grab the camera, and snap a picture. The whole process (from
taking a picture to getting the printout) takes an average of three minutes.
Most of that time is spent walking. :)

It's one of those "if it works, why fix it?" situations -- the whiteboard is
well-lit, when you crank up brightness/contrast in MS Photo Editor, it
produces crisp text on a black background. I'll try to post an example one
of these days.


<BCC4E214A1ED4D788427B9C8A1EB379C@ws11> 7bit

See also: www.piclist.com/techref/index.htm?key=whiteboard+image
Reply You must be a member of the piclist mailing list (not only a www.piclist.com member) to post to the piclist. This form requires JavaScript and a browser/email client that can handle form mailto: posts.
Subject (change) Whiteboard image extraction

month overview.

new search...