Y Gamma Curve Compression In Low Luminance Areas (S Gamma) - Sony SS-HQ1 Application Notes

- SS-HQ1 Application Notes -
Ver.1.0.0 January 7, 2005

10.4.4. Y Gamma Curve Compression in Low Luminance Areas (S Gamma)

The closer the AD input is to 0 (black level), the stronger the elongation will be. As a result, changes in
luminance near the black level seem to be very large. The DSP (CXD3172AR) in the SS-HQ1 system also has
a function for compressing the low areas of the gamma curve.
VIN
VRB
YGAMSON=0
IOY
YGAMSON=1
Fig 10.4-4 Gamma Curve Compression in Low Luminance Areas (S Gamma)
When YGAMSON (or UYGAMSON) is set to 1[h], the low luminance areas of the Y gamma curve are
compressed. The compression characteristics vary depending on the selected gamma curve (YGAMSEL or
UYGAMSEL).
Note that the compression level can be selected using the following parameters.
YGAMSLV (or UYGAMSLV) = 0[h]: Strong 1[h]: Weak
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