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Print Friendly Version Introduction
Whether you're downloading a picture from the Internet, scanning
in a family photograph, or creating a department logo, the graphic
file format you use will determine how good or poor the final
result is. In today's computer world there are no less than 40
different graphic file formats to choose from.
Each format has its own unique advantages, disadvantages, and
quirks. This document will describe the most common ones and give
you a comparison chart for future reference.
The File Formats
BMP
- BMP is the native Microsoft Windows file format, which means
it will work with all Microsoft programs, but not necessarily
other non-Microsoft applications.
- BMP is effective for graphics, but not as effective for photographs.
- BMP loads faster than other formats because the file is not
compressed. This allows the computer to simply display the pixels
on the screen instead of first taking time to calculate the
compression formulas, which are used with other formats. However,
this also means a larger file size.
JPG
- JPG files are good for emailing photographs to friends, and
for web page use, because the jpg file format is one of the
smallest.
- JPG is widely used on the Internet because the file is small,
often compressed to only 1/10 or 1/20 size. This allows jpg's
to be loaded by browsers quickly.
- JPG uses compression on every save which means that some
quality is lost each time the file is saved, and it cannot be
recovered. This is similar to copying a cassette tape to another
cassette tape. The quality is degraded with each copy.
GIF
- GIF files have historically been best, both for smallest
file size and for best quality, for use with line art. This
includes clip art, logos, and drawings.
- GIF is limited to only 256 colors, which makes it poorly
suited for photographic purposes.
- GIF also allows transparent backgrounds. This is important
for creating logos and icons.
TIF
- TIF is widely used for master copies of scanned data. As
images are scanned in they are saved in tif format, then manipulated
and saved in other formats.
- TIF files, unfortunately, are very large.
Comparisons
| FORMAT |
NOTES |
BEST USED FOR |
ADVANTAGES |
DISADVANTAGES |
| BMP |
Microsoft Windows native format. |
Logos and icons.
Within Microsoft Office. Word, Excel, PowerPoint, Publisher,
and Access can all view and share BMPs.
|
Retains its quality even when the image is enlarged. Loads
onto the screen quickly because it is not compressed.
|
Cannot be used on the Web. Most non-Microsoft programs cannot
view or save BMPs.
|
| JPG |
Used commonly on the Internet. |
Photographs.
Scanned images which will not be edited in the future.
|
Can be used on the Web. Small file sizes. Great for floppy
disks or emailing.
Good for Photographs.
|
Saving an image repeatedly in this format will result in
loss of quality. |
| GIF |
A cross-platform format. Both Windows and Macintosh can
view a GIF. |
Line drawings, logos, and clip art. |
The standard file format for the Web.
Option of transparent background.
|
Limited to 256 colors which is not useful for photographs. |
| TIFF |
A cross-platform format. Both Windows and Macintosh can
view a TIF. |
Scanned images
Photographs.
|
Allows for high resolution. Most scanning and image-editing
programs can save and open tif files.
|
Very large file size. |
File Sizes Table
- This is a hypothetical example to illustrate the file size
differences between each format. Read this table as follows:
"If you have an image stored in one format, what would
the size of that file be if it were saved in a different format".
- Although these results will vary depending on the type of
image being saved and other circumstances, this chart should
give you a sense of the different file sizes between each format.
| FORMAT |
FILE SIZE |
| BMP |
9.9 mb |
| GIF |
2 mb |
| JPG |
2 mb |
| TIFF |
9.9 mb |
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