Canon DR-5060F - Manual (Page 71)

69
Setting Detailed Scan Conditions
3
MEMO
Information on the gamma curve data is held internally by the scanner, and is
not cleared even if the scanner power is turned OFF. The gamma curve data
information is not changed until other gamma curve data is downloaded.
◆ Preparing Gamma Curve Data
Gamma curve data is stored in a text file (*.gmm) comprising 258 lines. This file
describes the output values for each of the 256 levels of input values.
Be sure to enter a comment in the 1st line of this file, and “256” in the 2nd line
of this file.
The 3rd line onwards are the output values for the input values. Set “0” for the
3rd line, “1” for the 4th line and a continually incrementing number for each line
until “255” is set for the 258th line.
Small values entered for the gamma curve data result in the image being
reproduced dark, and large values result in the image being reproduced light.
◆ Example
Normally, rightward-inclining gamma curves are prepared. However, a leftward-
inclining gamma curve can be prepared by inverting all output values. As a
result, the output image also will be inverted.
Gamma curve data
1st line : gamma curve
2nd line : 256
3rd line : 0
4th line : 1
5th line : 2
|
|
|
|
253rd line : 250
254th line : 251
255th line : 252
256th line : 253
257th line : 254
258th line : 255
Gamma curve data (inverted)
1st line : Inverted linear gamma curve
2nd line : 256
3rd line : 255
4th line : 254
5th line : 253
|
|
|
|
253rd line : 5
254th line : 4
255th line : 3
256th line : 2
257th line : 1
258th line : 0
Setting Scan Conditions
255
Output value
Input value 255
Gamma curve
255
Output value
Input value 255
Gamma curve