Table 1-8. Scanner Functions; Table 1-9. Data Format - Epson GT-9000 Service Manual

1.8 SCANNER FUNCTIONS
Table 1-8 summarizes the scanner's functions and settings. These functions, which are explained
on the following pages, are all controlled by software commands.
Function
1
Data format
I
Output resolution
Zoom
Reading area
Color mode
Digital halftoning
Color correction
Brightness
Sharpness
Gamma correction
Scanning mode
1.8.1 Data Format
The data format specifies the number of bits (from 1 to 8) used to represent the tone of each pixel.
Larger values enable a greater variety of tones or colors.
In monochrome mode, a format setting of 1 bit/pixel (bi-level data) provides only two tones: black
(0) and white (l). A setting of 2 bits/pixel (quad-level data) shows four tone levels (corresponding
to binary values 00, 01, 10, and 11). Eight bits/pixel provides for 256 shades of gray, generating a
result that has photographic quality.
When used with color mode, the data format defines the number of tones for each primary color
(green, red, and blue). A setting of 1 bit/pixel allows for eight colors (2x2x 2); 2 bits/pixel can
represent colors
64
(4 x 4 x 4).
represent more than 16 million different colors.
Data
1 bit/pixel
2 bits/pixel
3 bits/pixel
4 bits/pixel
5 bits/pixel
6 bits/pixel
7 bits/pixel
8 bits/pixel
If you want to reproduce images using more than 2 bits/pixel, use an output device capable of
supporting the resulting tonalities. Most microcomputer displays and printers cannot support
such tonalities. To achieve optimal results with these devices, normally use a 1 bit/pixel format
together with halftoning mode. The ESC D comma nd sets the data format.
Rev. A

Table 1-8. Scanner Functions

Command
29 settings, from 50 to 1200 dpi (main scan and sub scan
resolutions can be set inde~endentlv).
percentage can be set independently).
Offset and reading length.
Color line sequence, color page sequence, monochrome
mode, selectable drop-out color.
1 disable for the digital haiftoning mode, 3 halftoning
modes, 4 dither txdterns. 2 user download dither ~attems.
4 settings for the output device (available only for color line
sequence mode).
7 levels.
5 levels.
6 settings for the output device.
I
Normal, high speed.
Eight bits/pixel (providing a total of 24 bits for each pixel) can

Table 1-9. Data Format

Monochrome
Format
2 grays
4 grays
8 grays
16 grays
32 grays
64 grays
128 grays
256 grays
Available Settings
by step (main scan and sub scan zoom
Color
colors
8
64 colors
512 colors
4,096 colors
32,768 colors
262,144 colors
2,097152 colors
16,772,216 colors
Product Description
1-17