Curves filter possible?

One thing I miss during colour grading is using curves. Is this particularly difficult to implement as a filter - I noticed it wasn’t listed on the roadmap page. I have used levels, but with just three points (shadow, mid-tone and highlights) to modify the separate RGB and luma channels makes it harder to achieve a personal film-like contrast, compared to using multiple handles on the curves. Another thing that is useful is having a curves-specific eyedropper tool that, when clicked in the monitor window, will indicate that value on the curve for precise targeted changes.

Many thanks for all the on-going work done on Shotcut. After trying various Linux NLEs, it has become my preferred option. The usability and pleasant interface just gets out of the way to let you do your work.

I think I would say “yes”. It is kind of difficult.

Shotcut has access to a “curves” implementation in the underlying MLT video framework. This is the same implementation that KDENLIVE provides:
https://userbase.kde.org/Kdenlive/Manual/Effects/Colour_Correction/Curves
https://userbase.kde.org/Kdenlive/Manual/Effects/Colour_Correction/Bezier_Curves

So the implementation of an algorithm is already available. Someone would need to spend the time to implement a UI front-end for the filter. I think a simple filter with basic slider bars could be built easily. But we aspire for Shotcut to be easy to use. So someone would need to build a custom UI control to display a representation of the curve and allow user interaction with it.

Can you explain this further? Do you mean the eye dropper would indicate the original value of the pixel, or the new value of the pixel after the correction was applied?

I have been considering make a new video “Zoom” scope that would allow the user to zoom in on a set of pixels in a separate panel and view the value of individual pixels. I wonder if that would meet your needs.

This has been requested before:

You can use search query “Suggestion curves” to find something like this that has already been requested. \

Thanks for the insight about curves. Sorry for not seeing the earlier post on it.

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