OSSC Pro: Grouped Brightness and Contrast Adjustments

[SGGG2]

Currently the OSSC Pro only supports adjusting individual channels one at a time. Grouped brightness and contrast adjustments should really be standard, as broad adjustments are usually made before any fine tuning is done. Grouped adjustments should affect all channels equally whenever possible.

The menu would ideally look like this:

Brightness (number value)

R/Pr offset (number value)

G/Y offest (number value)

B/Pb offset (number value)

Contrast (number value)

R/Pr gain (number value)

G/Y gain (number value)

B/Pb gain (number value)

 

[Zacabeb]

That’s a great idea, but there are three complications I imagine could arise in designing those controls since the same menu is used regardless of whether the input signal is YPbPr or RGB. 🙂

First, the offset behaves differently with YPbPr and RGB sources. With YPbPr you adjust the Pb/Pr offsets to keep neutral color difference neutral and Y offset to adjust black level, but for RGB all the offsets control black level in unison. So for YPbPr a common offset control for all three channels is not appropriate, while for RGB it is.

Second, the gain controls saturation on the Pb/Pr signals and white level on Y, while it only controls overall white level with RGB. So that would also need to behave differently between YPbPr and RGB.

Third, there’s of course some interaction between the offset and gain controls and especially the gain controls don’t scale uniformly if they already have different values.

For RGB input having ganged offset and gain would be excellent for correcting black and white levels if the ALC doesn’t manage it properly, but for YPbPr you’d still have to adjust the gain and offset independently for each channel.

Maybe the YPbPr and RGB gain and offset controls could be separated, applying different values depending on whether the input is YPbPr and RGB? This would allow for RGB input to have those black and white level controls to alter all three values together. The gain and offset controls are expert settings after all (well, almost all the settings in the OSSCs are… 😀 )

[SGGG2]

Hmm, they’re described as brightness/ contrast in the wiki, but I adjusted values equally and it didn’t behave as expected. What I want are generic brightness and contrast controls. Gamma would be nice, too! Other than the backlight, I prefer to leave my display alone and make picture adjustments on the processor whenever possible.

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