Tool to create 3D lookup tables (.cube files) for video/image color manipulation.
Lutcraft is a command line program written in python3.
3D lookup tables are used to manipulate the look of an image or a video seqence. The map each point in a colorspace (e.g. RGB) to a new point in the same colorspace.
I guess if you found your way here, you know what 3D luts are and what they are used for ;-)
lutc lut-neutral.png
This creates a 'neutral' image.
Do pixel-level color adjustments as desired.
Tools I suggest are darktable, gimp, flowblade or cinelerra. Any other program doing pixel-level imaging will do fine.
Then save the image. I assume you call the file lut-x.png.
lutc -i lut-x.png lut-x.cube
This will output a 3D lookup tabble corresponding to the file lut-x.cube
lutc -h displays all available options.
The default lut size is 32.
To create a lut with a size of 64, use `lutc -s 64 lut64-neutral.png
Then manipulate the image as desired and create the .cube file:
lutc -i lut64-x.png lut64-x.cube
lutcraft can detect the size of the image automatically for most values of size.
The normal precision is 4 digits after the comma.
If you only need a lut with size 16, you can reduce the precision to 2 for smaller output files:
lutc -s 16 -i lut16-x.png -p 2 lut16-x.cube