*This is information on the most popular image formats and what they are for and
when to use them.*
If you want to save Pictures of real life (ie: trees, birds, people etc..) and
you want to save space and quality isn't a concern then the best format is .JPG.
If you want to save pictures of real life but quality is VERY improtant and you
have sufficient space then the .BMP is a good choice considering it can save in
24bit colour. If you have a program like Corel PhotoPaint or Adobe PhotoShop for
example than saving in their native formats is best (see documentation about
compressions for these formats as each programs will differ)
If you ant to save vector graphics (pictures that look like cartoons) that have
only a few individual colours then the .gif format is a good choice if you are
going to put these on the web. There are other formats more suitable for these
pictures if you have software that can open these formats and if they can they
will probably have native formats for this type of image. A popular format
however is .wmf (Most word proccesors can open this format). Saving vector
graphics as a .wmf (or a programs native vector graphics format) is better as it
allows you to increase/decrease the picture without degradation...saving it as a
gif converts a vector graphic into pixels which may pixelate on increasing the
size.
Documents are a bit more difficult but never fear....Here u can really choose
between all of the above EXCEPT .JPG The reason why is should you ever want to
use OCR software on the document then having it saved as a JPG may cause
problems as the quality will not be optmal and at the best of times OCR software
isn't very good. Should you want to use OCR software on them then ensure that
you scan them at a nice resolution (300dpi and above is good).
I personally choose to save this type of image as a "greyscale" 8bit .GIF
(unless colour is present) at about 600dpi. This keeps the file size as small as
it could be at 600dpi.
You could save it as a mono .BMP however with similar results.
*Summary*
BMP -
Real Life pictures with gradients and thousands of individual colours & large
file size
JPG -
Real Life pictures with gradients and thousands of individual colours & small
file size, bad quality
GIF -
Vector, no gradiesnts, 256 or less colours, small file size
WMF -
Exclusively for Vectors (can prevent some bmps from pixelating when increased)
TIFF -
For professional printing, good quality but big file size
PCX -
Fair quality, Fair File Size also for real life pictures or with lots of colours
I hope this helps you out
If any of this information is incorrect pls feel free to email me and correct me
Cheers
Kevin Hains
Cape Town
South Africa
Http://user.lia.net/hains/js2main.htm
Http://www.ct.lia.net
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