PKG_CHECK_MODULES(OPENEXR, [OpenEXR >= 1.0],
  AC_DEFINE(HasEXR,1,Define if you have EXR library)
  have_exr="yes",
AC_MSG_WARN( "OpenEXR support disabled: " $OPENEXR_PKG_ERRORS )
  have_exr="no"
) #end of PKG_CHECK_MODULES