17 Sep
1999
17 Sep
'99
12:43 p.m.
"Richard Erlacher" <edick(a)idcomm.com> wrote:
If there were a web site which would accomodate the
many thousands of pages
involved here I'd consider scanning the stuff and forwarding the bitmaps to
whoever wants them. Now, keep in mind that a typical TIFF of a printed page
in single-bit format is about 1 MB in size, and we're looking at a 1-2'-high
stack of paper with both sides printed in most cases. LEt's see. . . a ream
is about 1-3/4" = 500 sheets . . . let's say 10 reams . . . so we're
looking
at 10 GB, right (GAWD! . . . I hope I've miscalculated!)
No, for text and line art, just use TIFF Class F Group 4 compression.
It's lossless, and for typical pages at 300 DPI it's only about 50K.
Intricate pages somtimes wind up around 100K-120K.
And although not all software can deal with that format, the Group 4
fax compression is one of the native formats for PDF, so I now supply
all of my scanned documents as PDF files. For a few examples, see:
http://www.36bit.org/dec/
Yes, I know that some people hate PDF format, and that you can't read
them on a Commodore 64 or PDP-11/05. To which I say, too bad. I got
many more complaints about other formats. Some people even wanted text
pages in JPEG format, which is just about the worst conceivable format
for them, since JPEG is a lossy format designed for continuous tone
images.
I've hacked a version of the imagepdf program from Thomas Metz's PDFLIB
to directly import TIFF Class F Group 4 files into PDF files without
decompressing them, so that it's not necessary to buy the $300 Acrobat
program from Adobe.
Eric