/usr/include/dcmtk/dcmjpeg/ is in libdcmtk2-dev 3.6.0-9.
This file is owned by root:root, with mode 0o755.
..
/usr/include/dcmtk/dcmjpeg/ddpiimpl.h
/usr/include/dcmtk/dcmjpeg/dipijpeg.h
/usr/include/dcmtk/dcmjpeg/djcodecd.h
/usr/include/dcmtk/dcmjpeg/djcodece.h
/usr/include/dcmtk/dcmjpeg/djcparam.h
/usr/include/dcmtk/dcmjpeg/djdecabs.h
/usr/include/dcmtk/dcmjpeg/djdecbas.h
/usr/include/dcmtk/dcmjpeg/djdecext.h
/usr/include/dcmtk/dcmjpeg/djdeclol.h
/usr/include/dcmtk/dcmjpeg/djdecode.h
/usr/include/dcmtk/dcmjpeg/djdecpro.h
/usr/include/dcmtk/dcmjpeg/djdecsps.h
/usr/include/dcmtk/dcmjpeg/djdecsv1.h
/usr/include/dcmtk/dcmjpeg/djdijg12.h
/usr/include/dcmtk/dcmjpeg/djdijg16.h
/usr/include/dcmtk/dcmjpeg/djdijg8.h
/usr/include/dcmtk/dcmjpeg/djeijg12.h
/usr/include/dcmtk/dcmjpeg/djeijg16.h
/usr/include/dcmtk/dcmjpeg/djeijg8.h
/usr/include/dcmtk/dcmjpeg/djencabs.h
/usr/include/dcmtk/dcmjpeg/djencbas.h
/usr/include/dcmtk/dcmjpeg/djencext.h
/usr/include/dcmtk/dcmjpeg/djenclol.h
/usr/include/dcmtk/dcmjpeg/djencode.h
/usr/include/dcmtk/dcmjpeg/djencpro.h
/usr/include/dcmtk/dcmjpeg/djencsps.h
/usr/include/dcmtk/dcmjpeg/djencsv1.h
/usr/include/dcmtk/dcmjpeg/djrplol.h
/usr/include/dcmtk/dcmjpeg/djrploss.h
/usr/include/dcmtk/dcmjpeg/djutils.h