White balance neutral color picker not working (wayland)

Bug
1

What is your operating system?

ubuntu 22.04.01 (wayland)

What is your Shotcut version (see Help > About Shotcut)? Is it 32-bit?

22.10.25, installed from flatpack

Can you repeat the problem? If so, what are the steps?

  • open a video
  • add a white balance filter
  • click on the tool to pick up a neutral color
  • no matter where I click on the video, the color picked is black

I read about related problems on wayland with color pickers, so might be related? let me know if you want me to provide more information or install test things

X+

2

Works fine on Windows. (Shotcut: v22.10.25)
shotcut_uTUPrxcnhY

3

thanks,

for what I read, the newer versions of most linux distributions have switched to wayland, that - I’m not sure why, seems to make it difficult to read colors (at least I had the problem with sharing windows on calls)

and you seem to confirm it’s a problem specific to linux

4

I’ve just installed Shotcut on Ubuntu 22.04 and crashed into this bug. Color picker do not work as expected (gives black frame) in the wayland session (being it the default one on Ubuntu and most linux distro now). I tested flatpak, snap and appimage versions.
I also tried to log out and log in with the Xorg legacy session. It does work there so it seems it is definitely related to Wayland. This is not a workaround for me as I much prefer Wayland session (as an example I cannot use touchpad gestures in xorg).
As it is now becoming default on most of distro (latest being KDE Plasma) I feel a fix is needed.

EDIT: A possibly related bug was reported here Color Picker Malfunction but I posted here as I think problem on linux is more strictly wayland related.

5

Hi,

I found a workaround: instead of clicking on the color picker directly, click on the color box next to it

image

it opens a dialog to choose one color from a palette but you have the option to have custom colors

image

if you click on the + button, it opens a color picker that works

image

I am not familiar with shotcut development workflow and I didn’t try to create an issue, if the workaround works for you, could you investigate and report?

6

Thanks. I think this is not the best possible solution but could be a tempory workaround. The workflow of this tool is as described in the documentation:

The White Balance filter works well by following these steps:

Restore “Neutral color” and “Color temperature” to their defaults (6500 degrees).

Click on the eyedropper and position the crosshairs over an object which is supposed to be white, e.g. a white card, white shirt, etc. and click.

This can work by selecting either a white object on the frame or (better) a 18% gray reference target. It is not completely clear to me why one would want to select a custom color from a palette. Anyway in that dialogue a button “pick screen color” is also available that actually work in picking the color from the screen.

Schermata del 2024-03-27 13-25-53
Schermata del 2024-03-27 13-25-53600×541 40.7 KB

Using it in this way however do not allow for selecting an area to average colour as it works only on single point.

7

Also what is not clear to me (I cannot test this on he other eyedropper) is how it is supposed to work in the filter pipeline with other filters. Being it a white balance I would expect to ignore other filters that affect colour.
Let’s say I want to also apply color grading and later I decide to correct my white balance.
I can no longer use the eyedropper because it would take the white sample from the graded screen output so that I have to disable all other filters first.