Posted by Richard Crowley on 11/06/05 02:55

"Glenn" wrote ...
> I'm Glenn LeDuc, I work for an agency that helps people who are blind
> and visually impaired find work here in Washington State. For the past
> year or so I've been working on a making low cost devices to magnify
> books and other texts and objects for people with low vision that
> utilizes either a webcam or a composite video camera like a security
> camera or a camcorder, attached to a PC or to a television.
>
> Two of the features that people with some specific eye conditions find
> very useful, that the commercial devices that cost big money have, are
> the ability to display a negative of what is being viewed and the
> ability to display "false colors", so for example, a black and white
> page of regular text appears to be yellow text on a blue background.
>
> On the webcam / PC side I've found a program called dscaler
> (http://deinterlace.sourceforge.net/) that does the negative image
> with video from a webcam or from a composite camera run through a usb
> video digitizer. Also I've been told some hardware video processors
> can do negative of what is being displayed on a camera or from a
> video source in real time. The only devices that I've seen so far that
> have this abiliity are pretty expensive in terms of what I'm reying to
> come up with (~ $500 or more). I haven't had much luck finding
> anything that does false colors, either on the PC side or the video
> side.
>
> I'm wondering if any of the video professional or enthusiasts that
> read these groups could point me towards anything that could produce
> the negative and false color video on eith a PC or when displayed on a
> television? If anyone has any advice on this it would be greatly
> appreciated.

A standalone little box to make the image display in negative
form would be pretty easy to make (and inexpensive in moderate
quantities). A standalone box to also do arbitrary colors would
be a bit more complex to design and expensive to make. There
may already be a design for one or both of these out on the WWW
somewhere.

Should be able to do either/both on a computer if it is sufficiently
beefy. Are you sure there isn't software out there that does this
already?

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