
GL842 USB 2.0 2-in-1 Scanner Controller
Genesys Logic Inc.—All rights reserved.
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6 Image Sensor Timing
Can be programmed.
A. CCD: support 600,1200 or 2400 dpi CCD.
For example NEC, TOSHIBA, Sony ……etc.
B. CIS: support 600,1200 or 2400 dpi CIS.
For example Toshiba , Canon……etc.
7 Dummy Line
Support programmable dummy lines to resolve (overcome) Start/Stop problem.
You can insert dummy lines to reduce scanner stop and wait events (buffer full) or always non-stop.
A. Line base of dummy lines: The range of dummy lines is 0 line ~ 15 lines.
B. Adjustable dummy line: The range is CCD or CIS minimum shift out time to 2096k pixels time, which can
be adjusted by 1 pixel time increment.
8 Analog Front End Timing
External 16 bits Front-End for Wolfson WM8192, WM8199……etc.
9 Image Type
Support color, fine gray, fine line art, fast gray and fast line art scan.
Support color filters selection for gray and line art scans. The filters include Red, Green and Blue.
Note: The scan style of fine line art, fine gray or color are the same. So fine gray or fine line art scanning
speed is slow.
10 Bits Depth
16 x3 Bits true color , 16 bits gray level and one bit line art(Black & White).
Image data type: 16 bits , 8 bits and 1 bit data type.
11 Shading & Correction
16 x3 Bits true color , 16 bits gray level and one bit line art(Black & White).
A. White Shading & Dark Shading:
Internal white shading by pixel
(16 bits resolution) and dark shading by pixel (16 bits resolution), can be
Enabled or disabled By S/W.
Data arrangement: three line in mode: dark R1, white R1,dark G1,white G1,dark B1,white B1,
dark R2,white R2,dark G2,white G2,dark B2,white B2,
dark R3,white R3,dark G3,white G3,dark B3,white B3,……
one line in mode: dark R1,white data R1,dark R2,white R2,dark R3, white R3…
dark G1,white data G1,dark G2,white G2,dark G3,white G3…
dark B1,white data B1,dark B2,white B2,dark B3,white B3…
White shading formula: 2000H x Target / (Wn-Dn) = White Gain data ----- for 8 times system
White shading formula: 4000H x Target / (Wn-Dn) = White Gain data ----- for 4 times system
For example: Target = 3FFFH Wn = 2FFFH
Dn = 0040H and 8 times system operation
then White Gain = 2000H x 3FFFH / (2FFFH-0040H) = 2AE4H (1.34033 times)
B. Gamma Correction:
GAMMA correction table is calculated by S/W. The resolution is 16 bits gamma table.
Range: 0 to 64k (16 bits) input map 0 to 255 (8 bits) output.
Style: increment or decrement gamma curve style.
Note: If you bypass gamma correction, you can get 16 bits image data.
If you enable gamma correction, you can get 8 bits image data.