There seems to be a bug in LibRaw 0.19-Snapshot-20170212. To reproduce:
1. Download a Nikon Coolpix P330 raw sample. Here is one website to download from:
2. Use dcraw_emu to convert the raw file to TIFF (or some other format). The TIFF image will appear almost completely white.
On one image, LibRaw 0.19 says that the black level is 205 and white level is 4095. But if you convert the image to a DNG (using Adobe tools), the black and white levels encoded in the DNG are 3067 and 65000.
LibRaw 0.18.2 seems to be working fine.