Scanning docs

[Magnus Danielson]

From: Don Tillman <don at till.com>
Subject: Re: Scanning docs
Date: Wed, 23 Aug 2000 15:49:01 -0700 (PDT)

>    Date: Wed, 23 Aug 2000 15:05:12 -0700
>    From: Jim Patchell <patchell at silcom.com>
> 
>    How 'bout it gang.  Peter is scanning a bunch of documents
>    primarily from acutronics, which include ap-notes and circuits.
>    These documents are black and white.  Both text and drawings.
>    Which format would be best for posting on the internet?
> 
> Here are some quick basics...
> 
> If the source is still in business, get permission before placing the
> material on the web. 
> 
> PDF is great for documents that are composed like a book (chapted
> headings, page numbers, etc.) and are likely to be printed out in
> pages, but otherwise it's a drag.
> 
> JPEG is for photographs, paintings, and stuff that's of similiar
> content with lots of color shading.
> 
> GIF encodes colors with a lookup table, so it's great for drawings,
> schematics or logos.  GIF format can also assign a transparent color
> for doing non-rectangular images.

GIF is nowdays deprechiated for the benefit of PNG. PNG is the succsessor of
PNG but uses a unencumbered compression technique and can handle colors better
but is still a lossless compression technique. PNG is supported b6y the major
browsers and is a W3 standard.

> BMP is Microsoft specific and not appropriate for the web.
> 
> TIFF is for some specialized printers and not appropriate for the web.
> 
> Before you place the images on the web, do what you can to reduce the
> file size.  JPEGs can be often created with less resolution and the
> grainyness might not be a problem.  GIFs can often be created with
> a smaller color lookup table.
> 
> So the answer is likely to be to use GIF format with maybe 4 levels of
> gray.

Cheers,
Magnus