cv::remap() with CV_INTER_NEAREST produces bad results

edit

I'm getting these results when computing maps (initUndistortRectifyMap) with map type CV_16SC2. Both maps are getting created and sized correctly (by the initUndistort..() call), but when I use NEAREST interpolation, it looks like hell. CV_INTER_LINEAR also has artifacts, and cubic isn't much better. If I use CV_32FC1 it looks as I would expect.

I realize the 16SC2 won't be as accurate, and based on reading documentation I understand that NEAREST isn't supported unless the second map is valid, but that doesn't seem to be the problem (?)...

Any help is appreciated.

Thanks

Steve