Ricoh PRIPORT VT 2000 Series Service Manual page 65

28 February '91
2.7 Enlargement Processing: VT2300/VT2500
In reduction processing, pixels are discarded according to the selected
reduction ratio. In enlargement processing, pixels are added.
Enlargement processing requires main scanning enlargement and
sub-scanning enlargement.
Main Scanning :
Sub-Scanning :
2.7.1 Main Scanning Enlargement
When the magnification command is sent from the main control board
(CN402-19, 20, 21), the timing signal generator in the image processing
board sends the adding timing control signal. Pixels are added to the 4-bit
image data from the A/D converter according to the adding timing control
signal.
Enlarge Mode
115% (LT/A4 Version)
122% (A4 Version)
127% (LT Version)
141% (LT/A4 Version)
Main scanning is performed by systematically
adding pixels according to the enlargement ratio.
Sub-scanning is performed by changing the original
transportation speed according to the enlargement ratio.
Added Pixels
2 Pixels
3 Pixels
3 Pixels
9 Pixels
2-38
Pixel Ratio
15/13 Pixels (1.154)
17/14 Pixels (1.214)
14/11 Pixels (1.273)
31/22 Pixels (1.409)