Format comparison

Image format

GIF

JPEG

EPS (or vector)

TIFF

BMP

PCX

Acronym definition

Graphics Interchange Format

Joint Photographic Experts Group

Encapsulated Postscript

Tagged Image File Format

Microsoft Bitmap

PC Paintbrush

HTML suffix

filename.GIF

filename.JPG

filename.eps

filename.tif

filename.bmp

filename.pcx

primary purpose

web display

web display

construct files

construct files

splash screens

kids paint programs

Compression method

Lossless: Algorithm scans for blocks of color; no part of the image is eliminated

Lossy: Algorithm uses contrast to eliminate detail

none, naturally a very compact format

LZW is the most common, but not available in all programs

none

none

Image characteristics optimally compressed

Any image containing blocks of color, such as logos or cartoons

Any image containing significant detail and/or color transitions, such as color photographs

any image created with Adobe Illustrator, Corel, Canvass

n/a

n/a

n/a

features

GIF images have clean solid colors with nice sharp transitions between colors. File size is quite small.

JPEG images "muddy" the solid areas of color,especially near transitions between colors.

for constructing computer illustrations

for photos and bitmapped file manipulation

for opening screens, wallpaper.

hard to screw up

Transparency support (background color rendered invisible)

yes

no

yes

no

no

none

Interlacing support (image focuses during loading)

Available; use GIF89a format in Photoshop

Available; use ProJPEG, available through BoxTop Software and other sources

no

no

no

none

Bit-Depth, number of colors

1,4,8- bit

1,4,8,16,24,32- bit

1,4,8,16,24,32- bit

1,4,8,16,24,32- bit

256 color

256-color

Example, Graphic Art, Logos

If there are large areas of uniform color (like maps, logos, cartoon-like images, GIF is superior in quality and smaller size

If there are few areas of uniform color or textures, JPEG will make a smaller file and will most likely look better.

the ideal medium for logo development. Sometimes enhanced, like with Corel (cdr), Adobe Illustrator (ai)

good to use in final step of logo preparation, for having precisely controlled anti-aliasing

Windows opening screen

if PCX is the native format of a paint program, get another program

Example, Photograph

excellent results for color and bw photos, particularly B&W - someitmes compresses B&W better than jpeg if theres a lot of uniform areas

JPEG yields best compression on most photographs

do not use for photos. When you do, it just stores a TIFF image inside an EPS file

the perfect contruct file for photo retouching

can display any properly dithered photo

if PCX is the native format of your paint program, get another program

Animations

the standard for web animation. All banner ads are GIFs

Although there are JPEG animations, this is a poor format at best for animations

no

no

no

no