LUT3DSIZE

LUT3DSIZE is a parameter used in 3D Look-Up Tables (LUTs) that defines the resolution or dimensions of the LUT. A 3D LUT is a data structure used for color transformation, mapping input color values to output color values. It's essentially a three-dimensional grid where each point within the grid represents a specific input color combination and stores the corresponding output color.

The LUT3DSIZE determines how many "points" or "nodes" exist along each of the three axes (typically red, green, and blue) of the LUT. For example, a LUT3DSIZE of 17 would mean the LUT has 17 divisions along the red axis, 17 along the green axis, and 17 along the blue axis, resulting in a 17x17x17 grid. A larger LUT3DSIZE provides more discrete points, allowing for finer control over color grading and more accurate representation of complex color transformations. However, increasing the LUT3DSIZE also increases the memory footprint and computational resources required to store and process the LUT.

Choosing an appropriate LUT3DSIZE involves a trade-off between precision and performance. Smaller LUTs are faster to process but may introduce banding or artifacts in the color transformations due to their coarser resolution. Larger LUTs offer smoother gradients and more nuanced adjustments but can be more demanding on hardware. The optimal LUT3DSIZE often depends on the specific application, the complexity of the desired color transformation, and the capabilities of the processing hardware. Common LUT3DSIZE values range from 9x9x9 to 65x65x65 or even larger in professional contexts.