Glossary of Terms
Bitmapped or Raster Graphic (TIFF, EPS)
Refers to graphics generated by a scan, marking every point as either black, white or another color. Each point for which there is a value is called a pixel. Pixels can b e edited only in a paint or photopaint program such as Photoshop, Corel Paint, Colorlt, etc. Resolution is dependent on the scaled size of the file.
Vector Graphic (EPS)
A method of creating pictures in a drawing program such as Freehand, Illustrator and CorelDraw! by drawing lines in particular positions. The picture can be enlarged or reduced without loss of sharpness, since the picture is not made up of a fixed number of pixels.
EPS (Encapsulated Postscript)
A file type created by a wide variety of programs which contain the vector and bit map information necessary to print the page successfully. An EPS is not compressible and thus tends to be very large when used to contain bitmap graphics.
An EPS graphic was required to import a bitmap with a clipping path into PageMaker or Quark; however, upgrades to both programs now allow a TIFF to be used.
JPEG (Joint Photographic Experts Group)
A file format for storing bitmap images using lossy compression. This type of format is often used to send files via modem. The file can be compressed to a very small size but blurring and toss of detail occurs.
PDF (Portable Document File)
A file format which represents a document independent of the software, hardware and operating system used to create it. Files can be exchanged easily between platforms and printed to any Postscript printing device. Editing options am limited.
This graphic file format was an early one developed for the Macintosh platform. Not recommended.
TIFF (Tagged Image File Format)
A file format used for storing bitmap images. Can store very large images with millions of colors. This is the most common format for exchange of bitmappedf iles.
WMF (Windows Metafile)
This format is similar to the PICT format. Not recommended.
DPI (Dots Per Inch)
Refers to the resolution of a printing output device. The smallest dot produced by the device determines the printer’s dpi. Range is from 300 dpi (desktop laser printer) to 3000 dpi (imagesetter).
LPI (Lines Per Inch)
A measure of the resolution of a halftone screen used to reproduce continuous tone images on a printer or press. A 600 dpi laser printer can produce the equivalent of a 100 lpi halftone. When higher resolutions are needed, the file should be output to a 2400 dpi imagesetter.
PPI (Pixels Per Inch)
Refers to the resolution of the CCD chips in scanners and digital cameras. The higher the PPI, the more detail and enlargement can be had.
RIP (Raster Image Process)
The interpretation of a page description language, such as Postscript, to a raster format at the resolution and in the format required for a specific output device or imagesetter.
A measure of the amount of detail that can be shown in the image produced by a printer or screen.
A compression method that does not remove data to achieve compression.