Canon 800II Manual Do Utilizador

32

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Gamma curve data consists of a 258-line text file (*.gmm) containing the output
values for the 256 levels of input values.
Always enter a connect as the first line of the gamma curve data and “256” in the
second line to indicate the number of data items.
Lines 3 onwards set the output values for each input value, starting with the output
values for “0” in line 3, “1” in line 4 and so on through to the output value for input
value “255” in line 258.
Smaller values in the gamma curve data give a darker image while larger values
produce a lighter image.

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Normally, the gamma curve leans to the right. However, the leftward-leaning gamma
curve shown in the lower figure below inverts all the output values so that the result-
ing image is also 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

Gamma curve data (inverted)

0

255

255

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

(Gamma curve)

0

255

Input value

Output value

(Gamma curve)

Output value

Input value

255