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Re: File Formats (was wire gauge)



possibly off topic, except that it has bearing on the posting of pictures
for any purpose, not just wire charts, but arcs-n-sparks as well...

on that fateful day 8/8/00 12:02 PM, Tesla list uttered:

> Using a monochrome picture I have ("motor_1.gif"), I saved it as a
> monochrome BMP,
> GIF, TIFF using LZW compression, and 256 color JPG at 25% with
> progressive encoding.  The results are:
> BMP:  759k
> GIF:  41k
> JPG:  200k
> TIFF:  38.8k

I'd like to clarify something:

The reason the file expanded is because the file was already compressed.
The GIF format _includes_ a lossless compression.

 When you attempt to compress an already compressed file, it will almost
always expand, no matter what algorithm is being used.  Note also that,
assuming the original is in good condition with a large number of colors
(256 or more), JPEG compression can be run up to 50% or more with very
little perceptible image degradation.  But JPEG is intended for photo-type
images, not line drawings or pictures of text (which look like line drawings
to a graphics program).

- Gomez

.................................
aibohpphobia: fear of palindromes