[DigiCam] Re: DigiCam for OCR

[George Reis]

dennisfey at attbi.com wrote on 6/1/03 10:50 AM:

> Now, only 300dpi is acceptable for my OCR.  Converting this to my
> resolution requirement for a digicam gets me mucked up.   If I'm scanning a
> 8.5x11 page at 300dpi, this appears to be equivalent to 2550 pixels X 3300
> pixels.  Now, this might mean I need a 8 million+ digicam for 16-bit color
> shots, printable at 300dpi, but surely it doesn't mean I need that for
> shooting 2-bit, b/w, 300dpi-equivalent TIFFs!
> 
> How do I determine my resolution requirement at 2-BIT (b/w), NOT 16-BIT
> color depth?

This isn't an easy question, as you know. Unfortunately, the only way to be
certain if you will get what you need is by testing it. Additionally, if
your lighting isn't very even, then the conversion to 2 bit may get a lot of
artifacting in the image, causing problems with your OCR.

300 PPI (even at 2 bit) is a lot of resolution. If you have six lines of
text in an inch, this gives you 50 pixels per line of text (including
spaces), which is quite substantial (you can probably get by with about 10 -
12 pixels per line of text).

George Reis
--
Imaging Forensics <http://www.imagingforensics.com>
Specializing in digital imaging consulting, training, analysis and
enhancement for the law enforcement, investigative and legal communities.