Hi Jing,
1
Evalglare is very protective to make sure that the luminance values are correct. In this case, your circular mask and vignetting functions indent the previous exposure values as a comment, and evalglare rejects the image type as a result.
What you can do in this case is to open the HDR in a nice text editor (such as Notepad++) and delete all of the tabbed-in lines from the header. Save the result, and verify that the luminance values are correct in an external viewer program (HDRscope, wxFalsecolor, Photosphere on Windows). Then evalglare should work.
2
If the image is a fisheye, use evalglare -vta -vh 180 -vv 180.
(note: I accidentally put down -vtv before. Your image is most likely an angular fisheye (vta).)
3
Clotilde Pierson just published a very nice tutorial in Leukos. You should check it out! Our conference papers on HDR accuracy might be helpful supplemental reading.
BR,
Alstan