Thanks to Roi and his students few bugs were discovered and (hopefully) fixed in these pull requests. Both relate to the Matlab packages:
the images are now read by a unified function openpiv_imread that treats TIFF images (12-bit from Insight) or any other format accordingly.
the directory listing is also fixed, there was a bug with the upper-case extensions on Mac OS X platform
there were two bugs:
a) the y-axis direction was upside-down, compatible with the C++ version, but not with the openpiv-matlab, openpiv-python or Insight
b) the profiles were upside-down when used by columns.