Fixed compilation problem on ubuntu
Fixed compilation problem on ubuntu

BioMedIA/IRTK,BioMedIA/irtk-legacy,BioMedIA/IRTK,ghisvail/irtk-legacy,ghisvail/irtk-legacy,ghisvail/irtk-legacy,sk1712/IRTK,BioMedIA/irtk-legacy,BioMedIA/IRTK,sk1712/IRTK,sk1712/IRTK,BioMedIA/IRTK,ghisvail/irtk-legacy,sk1712/IRTK,BioMedIA/irtk-legacy,BioMedIA/irtk-legacy