Possible conflict: http://sourceforge.net/p/mediainfo/bugs/50/
For example, if you have a file named 'a?.mp4' running the command through bash:
will return no output with a return code of 1. If mediainfo is trying to expand the tokens (rather than rely on the shell to do so), one would think that it should still match 'a?.mp4' (along with 'ab.mp4' etc) but this doesn't seem to be the case.
It would be better if we could force mediainfo to not bother trying to expand wildcards (perhaps an additional CLI param?), leaving this job to the shell, but this could be more work.
Renaming the file to not have these special characters allows mediainfo to dump the appropriate info.
Nb: tested on v0.7.67. 0.7.68 doesn't look like it fixes it.