Omnipage Pro works nicely, will read/scan just about anything ( I'm using it to slowly OCR stuff the PDFs from the SPIES archive ) Unfortunatly it costs a bundle. You gets what you pay for. ----- Original Message ----- From: "Jules Richardson" <julesrichardsonuk(a)yahoo.co.uk> To: <cctalk(a)classiccmp.org> Sent: Friday, September 12, 2003 6:01 AM Subject: OCR'ing old manuals that'll to and make a bell ring.

Jules Richardson wrote: Distributed Proofers seems to prefer Abbey Finereader, but it also costs money. It apparently does very well with images that others choke on.

Omnipage Pro At 03:01 AM 9/12/03, you wrote:

"Antonio Carlini" <arcarlini(a)iee.org> wrote: Note that you should NEVER save scans of text and line art in a lossy form such as JPEG. JPEG works for continuous-tone images such as photographs by deliberately throwing away high-frequency components. Test and line art contain sharp black-to-white transitions (and vice versa, of course) which get smeared by this compression, resulting in a blurry image. For text and line art, a lossless bilevel compression such as G3 or G4 fax format (used in some TIFF files), JBIG, JBIG2, Flate (used in some PNG files). You can't assume that because you save in TIFF or PNG that you get a specific form of compression, since they are very broad standards that support multiple compression types. Sometimes people tell me that JPEG is alright if you only compress slightly. The edges still get blurry, and the resulting file size is generally *MUCH* larger than if you use G4 or JBIG. JBIG gets 10-20% better compression than G4, but it is patented, so I don't use it. Flate usually compresses somewhat better than G4, and is not patented, but I'm not sure how it compares to JBIG. I'm not using it because support is not widespread yet. G4 works well because it can be wrapped in PDF and used by any PDF viewer. Bilevel compression doesn't work well on continuous tone images, so JPEG should be used for those. The main dilemma for scanning is pages that contain a mix of text/ line art and continuous tone images. My personal reccomendation for these is to either scan the page twice, in B&W and color (or gray scale), or to scan it once to uncompressed color (or gray scale) then convert to both bilevel and JPEG in software. Apparently some "best practice" policies for document archiving specifically state that a document should only be scanned once. I think they're just trying to minimize handling of fragile documents, so I don't think they really mean that taking two scans of a page (consecutively without manipulating the physical document) is bad. These "best practice" policies also recommend a minimum of 600 DPI, which is reasonable for continuous tone images but is normally overkill for text and line art. I typically use 300 or 400 DPI. I've written a program to take B&W TIFF files and color or B&W JPEG files and produce a PDF file: http://tumble.brouhaha.com/ My future plans for tumble include compositing text and line art with continuous tone images on a single page. I've got a script for GIMP to take an uncompressed color or gray scale scan (in PGM or PPM format), allow manual selection of the continuous tone images, then save two separate files. I've been thinking about trying to automate this by having the filter use histograms and FFT to locate the images. I'm not sure when I'll have time to work on this further, though. Eric

--- Eric Smith <eric(a)brouhaha.com> wrote: > Absolutely - I tend to save everything as TIFF format and in as high a resolution as seems practical (occasionally I'll use Paint Shop Pro's format if I need something with layer support). I'm not a big fan of JPEG images... I'm hoping to get away with scanning things at 300dpi (in this case it's all printed documentation with a few diagrams, rather than colour images). Not only will that save space but I can also use my older scanner (which won't do more than 300dpi I believe, but is at least SCSI and so should transfer data to the host a little quicker). I'm a little wary of saving things in mono as somebody else mentioned - I'm sure that could have a negative effect on the OCR process at a later date. Greyscale (8 bit) I expect is fine though. I'll have a look at that - might come in handy. :-) Image processing/manipulation I do find pretty interesting.,,, cheers Jules ===== Backward conditioning: putting saliva in a dog's mouth in an attempt to make a bell ring. ________________________________________________________________________ Want to chat instantly with your online friends? Get the FREE Yahoo! Messenger http://mail.messenger.yahoo.co.uk

Antonio Carlini wrote: Correct. - Paul

I usually use greyscale with a good interpolator to increase my dpi 2 to 3x linearly (increasing the dotcount 4 to 9x overall) and Then cast it to 1 bit. Works great. Just going directly from 8 bit to 1 bit at the same dpi is a waste of good information. John A.

http://www.brouhaha.com/~eric/retrocomputing/dec/doc/oml/ Personally, I don't think OCR for this will be of even the slightest use, but you are of course welcome to try.

vance(a)neurotica.com wrote: I'm interested also. I'd be happy to post a PDF version of the word doc. -- hbp