dcmj2pnm dcm convert to png

 dcmj2pnm --set-window 300 800 +on 46.dcm 46.png

dcmj2pnm --set-window [window_center] [window_width] +on [dicom_file] [output_file]

https://support.dcmtk.org/docs/dcmj2pnm.html