#11 Give user post-gamma control

[Richard M.]

Luminance-HDR does sRGB mapping of the output for most operators. This has an effective gamma of about 2.2. Many operators do not need post-gamma (in spite of what the pfstmo man pages say) and other operators may benefit from a smaller post-gamma value. This is a feature request to add the following:

• a checkbox to disable the sRGB mapping of output (see below for suggested default
  settings), and
• a slider, which is enabled when the checkbox is set, to allow the user to set a
  custom post-gamma value (default 1.0).

In my experiments with pfstmo, the following operators gave better results without any post-gamma or sRGB mapping applied:

• Drago
• Fattal
• Mantiuk '08 (I believe Luminance-HDR already omits the sRGB mapping for this
  operator, as the pfstmo man page states post-gamma is not required.)
• Pattanaik
• Reinhard '02
• Reinhard '05

The remaining operators work best with the sRGB option.