Create your own lookup table (LUT)

SensorSDK comes with many LUTs useful for colormapping, also called colormaps. See Use LUT Mapping for visualization for the complete list.

For specific applications, you might require a custom LUT. This section describes how to create your own LUT you can use with the LUT Mapping node.

Image file format

While the LUT Mapping node takes a Texture2D as input for the LUT, the usual way to provide the LUT is via an image file asset.

The image file can be in any format supported by Unity, like PNG or BMP. See Supported Asset Types for the list of supported image file formats.

The image needs to have at least 3 channels. If the image has a 4th channel, it's ignored.

LUTs provided by SensorSDK all have dimension 256 × 32, but this isn't a requirement. An image can have any width or height. LUTs use the first row of the image, but a larger image height makes the LUT more visible in the Project window.

Texture Import Settings

When you select an image file in the Project window, the Texture Import Settings appears in the Inspector window. Any changes to these options are saved into the meta file next to the image file.

Here are the recommended settings for colormaps:

  • Disable sRGB (Color Texture).
  • Set Alpha Source to None.
  • Disable Generate Mipmaps.
  • For PNG files, enable Ignore PNG Gamma.
  • Set Wrap Mode to:
    • Clamp: For sequential or diverging colormaps.
    • Repeat: For cyclic or qualitative colormaps.
  • Set Filter Mode to:
    • Bilinear: Use if the values in the LUT have no discontinuities.
    • Point (no filter): Use for qualitative colormaps.
  • Set Compression to None.

For a complete description of the settings, see Texture Import Settings.