Kodak 9500 Document image level, Error diffusion mode, Gray scale image, Gray levels, Header

Document image level

Rank associated with a type of document. Up to four levels — Level 3, Level 2, Level 1, and Level 0 — can be used. The level can be set automatically using a Patch Reader accessory, manually by pressing the Footswitch, by pressing a Level key on the control panel, or by sending a scanner-unique Level of Next Document command.

Error diffusion mode

Compromised between binary thresholding and screening; used for documents containing both continuous tone photographic and text information. It simulates gray scale while retaining text readability.

Gray scale image

Refers to a processed image that consists of pixels which are assigned values based upon a range of gray shades, as opposed to thresholded images in which each pixel is either black or white.

Gray levels

Discrete shades of gray.

Halftone image

Refers to a printed image that simulates a continuous tone image. The simulation is achieved by using a series of dot patterns. Newsprint pictures are an example of halftoned images.

Header

Contains information associated with the raster image file. Consists of fixed fields (provided by the host computer) and scanner-determined dynamic fields (image sequence number, image size in bytes, image level).

Image address

Contains fixed and dynamic information which can be used for image retrieval.

Initiator

A SCSI device (usually a host) that requests an operation to be performed by another SCSI device.