When using XPro Semi-Global Matching the output point cloud LAS file is RGB encoded with a different bit depth than the input images. The input images are 8-bit, but the output RGB encoded values in the LAS file are 16-bit.
The LAS specifications requires that the RGB values be 16-bit. The LAS Specification document is attached to this article. Here is an excerpt from page 13:
The Red, Green, Blue values should always be normalized to 16 bit values. For example, when encoding an 8 bit per channel pixel, multiply each channel value by 256 prior to storage in these fields. This normalization allows color values from different camera bit depths to be accurately merged.