Contrast slider has no effect

[adrianghc]

Describe the bug
Sometime in the past few weeks maybe, the contrast slider has stopped working. I wonder if this might be related to the workaround you implemented for #48?

To Reproduce

1. Enable advanced scan settings.
2. Scan a page.
3. Change the contrast setting with the slider and scan the page again.

Expected behavior
There should be a noticeable change in contrast between the two scans.

Log data
log20220430.txt
Looking at the log data, it seems that contrast is always either 0 or null, regardless of the value that I set through the slider.

[simon-knuth]

Yes you're right, there is an unintended connection between the brightness and contrast values. The contrast is in most cases being ignored if the brightness is set to its default value (usually 0).

I believe I'll push out a small update prior to the next release to get this fixed over coming days.

[simon-knuth]

Should be fixed in v3.1.3 - thank you for reporting this!

[adrianghc]

And so it is. Thanks a lot! :)