This feature is used to tune the global tone adjustment
submodule of LTM, which calculates the LTM gain from the input Y and Y_ltm images and
applies the LTM gain to the input RGB image to generate the tone mapped RGB output
image.
Procedure
Next to Saturation Control Enable, select
Enable or Disable to control
whether to enable saturation control for LTM.
In the Luma Threshold text box, enter the luma
threshold.
If the input luma is less than the threshold, then a certain LTM gain is
applied.
Next to Alpha Gain LUT, click View/Edit this
Table and edit the alpha gain LUT in the prompted dialog.
The alpha gain LUT contains 121 entries.
You can use one of the following methods to update the alpha gain LUT:
Double-click and edit a single cell in the LUT.
Click Edit and update the LUT cells in the
prompted Edit Table dialog.
The cells must be
specified in the same order as those in the LUT and separated by a
comma (,) in each row.
Click Export to export the LUT cells to a
.csv file, edit the file, and then import the
updated LUT from the .csv file.
The order of the
cells in the exported .csv file is the same as that
in the LUT.
Next to Alpha Luma LUT, click View/Edit this
Table and edit the alpha luma LUT in the prompted dialog.
The alpha luma LUT contains 129 entries.
The methods of updating the alpha luma LUT are similar to those of updating
the alpha gain LUT described in Step 3.
Next to Saturation Control LUT, click
View/Edit this Table and edit the saturation control
LUT in the prompted dialog.
The saturation control LUT contains 257 entries.
The methods of updating the saturation control LUT are similar to those of
updating the alpha gain LUT described in Step 3.
Results
The tuning results are printed in the Console view in real
time.
The image displayed on the VTunerServer side is updated.