Gamma - Photon Focus MV3-D640I-M01-144-G2-12 User Manual

9 Pixel Data Processing

9.4.2 Gamma

The 'Gamma' mode performs an exponential amplification, configurable in the range from 0.4
to 4.0. Gamma > 1.0 results in an attenuation of the image (see Fig. 9.10), gamma < 1.0 results
in an amplification (see Fig. 9.11). Gamma correction is often used for tone mapping and
better display of results on monitor screens.
300
250
200
150
100
50
0
0
Figure 9.10: Applying gamma correction to an image (gamma > 1)
300
250
200
150
100
50
0
0
Figure 9.11: Applying gamma correction to an image (gamma < 1)
64 of 121
Grey level transformation − Gamma: y = (255 / 1023
200 400
x: grey level input value (10 bit) [DN]
Grey level transformation − Gamma: y = (255 / 1023
200 400
x: grey level input value (10 bit) [DN]
γ γ
) ⋅ x (γ ≥ 1)
600 800
γ γ
) ⋅ x (γ ≤ 1)
600 800
γ = 1.0
γ = 1.2
γ = 1.5
γ = 1.8
γ = 2.5
γ = 4.0
1000 1200
γ = 1.0
γ = 0.9
γ = 0.8
γ = 0.6
γ = 0.4
1000 1200
MAN076 09/2017 V1.0