[Dcmlib] how to tell whether the dicom is signed or unsigned

[acid]

dear sir,
I am a begginger in dicom,and I have a read dicom function developed based on gdcm library,
and it can only support 8/12/16bits,
and I dont know how to make sure whether the loaded file is signed or unsigned format,
and how to process signed format image,
I wonder if you can help me out of here,
very very appreciate your help!!


Sincerely,Alison