(Graphic Interchange Format) A graphics format for files being transmitted
by modem. This is a highly compressed format designed to support colormapped
images with less than 8 bit color. Created at CompuServe.
8- or 16-bit indexed color, capable of single color transparency,
large file size results from pixel color changes in any horizontal
line, not best for images with smooth fades or gradients from one color
JPG/JPEG (.jpg or .jpeg)
This format compresses pictures by the way data is stored and also by
discarding colors beyond what the human eye can see. Because it discards
data this algorithm is referred to as "lossy," meaning it
will not be identical to the original image. You can choose how much
data (image quality) you lose when you save your file. Created by the
Joint Photographic Experts Group.
Preferable for photos with subtle color changes and fades from one color
to another. Generally small file sizes with tunable quality, does not
accomodate transparency, not compatible with all older browsers (estimated
to be between 1-15% of any given site).
Web movies are of two types: downloadable and streaming. Downloadable
movies are disappearing due to advances in streaming/delivery technologies.
Many streaming video formats require a server that uses proprietary
or common Internet protocols to ensure efficient distribution. QuickTime
3.0 and VivoActive are both serverless software-only solutions, and
thus appropriate for a wide audience.
All movie types are compressed with a "codec" (COmpressor/DECompressor)
so they can travel efficiently by modem over phone lines. File formats
have different suffixes depending on their point of origin. (.mov .mpg
.avi .ram .vdo)
Free plug-in (or $30 with editing capabilities), no server needed. Treats
audio and video separately to maximize compression (codec) choices,
also will allow delivery from multiple sources according to user-set
Real Video (.ra or .ram)
Currently the most popular format, needs proprietary plug-in that can
be free. Server is rather costly--many ISPs have server installed for
your use. Authoring tools rely on a codec plug-in for popular movie-editing
TIFF (.tif or .tiff)
(Tagged Image File Format) A common bit mapped format which includes a
standardized header that carries information about the exact data structure
of images. Similar to GIF, TIFF supports image types additional to
indexed color. Files are often very large. Created by Aldus, Microsoft
Some applications (Morph, FlipBook) will allow for printing separate frames
of a movie to be assembled into a flipbook.
(Windows Metafile Format) A graphics format commonly used by Windows applications.
PICT for Premiere
A bit-mapped graphics format common in the Macintosh community, increasingly
being recognized elsewhere as an intermediary format especially effective
at compressing images that contain large, flat areas of color. Saving
a PICT image with 32 bits will include 1 alpha channel for use in masking
or transparency for superimposition in a movie-editing application,
like Premier. This format describes black and white (PICT) and/or color
(PICT2) bit-mapped objects.