Barco K5960051-01 User Manual
Barco - RHDM-1701 - User manual 157
Video signal processing
5.4 Effective gamma
The Rec.709 encoding equation assumes a linear tail and a power function with an exponent 0.45.
However, because of the linear offset and scaling, it is not correct to state that the Rec.709
encoding equation is described by a gamma of 0.45. The Rec.709 encoding equation is best fitted
with a pure power function with an exponent 0.52 (see figure below). We call this “best fit” the
“effective gamma
However, because of the linear offset and scaling, it is not correct to state that the Rec.709
encoding equation is described by a gamma of 0.45. The Rec.709 encoding equation is best fitted
with a pure power function with an exponent 0.52 (see figure below). We call this “best fit” the
“effective gamma
”.
Figure 55: The Rec.709 encoding equation fitted with a power function
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