==================================
DICOM TOOLKIT (DCMTK) INSTALLATION
==================================


PRE-REQUISITES
==============

The DICOM toolkit (DCMTK) needs to be compiled with a C++ compiler.  We
recommend using the GNU C++ compiler in versions higher than 9.5.0 (most of the
development for this release was done using GNU gcc 12.2.0 on Debian Linux and
GNU gcc 13.3.0 on Ubuntu Linux).  The software is also known to compile using
Clang and Microsoft Visual Studio.

Compatibility with other C++ compilers is unknown, however, we have tried to
keep language demands to a minimum.

You will need several hundred Mbytes (or even more than a Gbyte) of disk space
to compile all the software.


SUPPORTED SYSTEMS
=================

Microsoft Windows
-----------------

The DCMTK software can be compiled under a native Microsoft Windows environment
(see section "Microsoft Windows with CMake" below for more information).

The current DCMTK software release 3.7.0 successfully compiles on the following
operating system / hardware / compiler combinations:

   Windows 10      / Intel x86    / Microsoft Visual C++ 2017 Community (VS 15)
   Windows 10      / Intel x86    / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 10      / Intel x86    / Microsoft Visual C++ 2022 Community (VS 17)
   Windows 10      / Intel x86    / MinGW Clang 17.0.6 (i686-w64-windows-gnu)
   Windows 10      / Intel x86    / MinGW gcc 13.2.0 (i686-w64-windows-gnu)
   Windows 10      / amd64|x86_64 / Microsoft Visual C++ 2017 Community (VS 15)
   Windows 10      / amd64|x86_64 / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 10      / amd64|x86_64 / Microsoft Visual C++ 2022 Community (VS 17)
   Windows 10      / amd64|x86_64 / MinGW Clang 17.0.6 (x86_64-w64-windows-gnu)
   Windows 10      / amd64|x86_64 / MinGW gcc 13.2.0 (x86_64-w64-windows-gnu)
   Windows 11      / Intel x86    / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 11      / Intel x86    / Microsoft Visual C++ 2022 Community (VS 17)
   Windows 11      / Intel x86    / MinGW Clang 18.1.8 (i686-w64-windows-gnu)
   Windows 11      / Intel x86    / MinGW gcc 14.2.0 (i686-w64-mingw32)
   Windows 11      / amd64|x86_64 / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 11      / amd64|x86_64 / Microsoft Visual C++ 2022 Community (VS 17)
   Windows 11      / amd64|x86_64 / MinGW Clang 18.1.8 (x86_64-w64-windows-gnu)
   Windows 11      / amd64|x86_64 / MinGW gcc 14.2.0 (x86_64-w64-mingw32)


Unix (or lookalikes)
--------------------

The current DCMTK software release 3.7.0 successfully compiles on the following
operating system / hardware / compiler combinations using the instructions
given below:

   FreeBSD 14.3    / amd64|x86_64 / Clang 19.1.7
   Linux 5.14.0    / amd64|x86_64 / GNU gcc 11.5.0    (AlmaLinux 9.6)
   Linux 6.1.0     / Intel x86    / Clang 14.0.6      (Debian 12)
   Linux 6.1.0     / Intel x86    / GNU gcc 12.2.0    (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / Clang 14.0.6      (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / GNU gcc 12.2.0    (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / GNU gcc 13.2.1    (Alpine 3.20 musl libc)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 11.5.0    (Ubuntu 24.04.3 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 12.4.0    (Ubuntu 24.04.3 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 13.3.0    (Ubuntu 24.04.3 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 14.2.0    (Ubuntu 24.04.3 LTS)
   Linux 6.8.0     / amd64|x86_64 / Clang 18.1.3      (Ubuntu 24.04.3 LTS)
   Linux 6.8.0     / s390x        / GNU gcc 13.3.0    (Ubuntu 24.04.2 LTS)
   Linux 6.8.0     / s390x        / Clang 18.1.3      (Ubuntu 24.04.2 LTS)
   MacOS X 15.5    / amd64|x86_64 / Apple Clang 17.0.0
   MacOS X 15.5    / amd64|x86_64 / GNU gcc 15.2.0
   MacOS X 15.5    / arm64        / Apple Clang 17.0.0
   MacOS X 15.5    / arm64        / GNU gcc 15.2.0
   NetBSD 10.1     / amd64|x86_64 / Clang 18.1.8
   NetBSD 10.1     / amd64|x86_64 / GNU gcc 10.5.0
   OpenBSD 7.7     / amd64|x86_64 / Clang 16.0.6
   OpenIndiana     / amd64|x86_64 / GNU gcc 14.3.0    (OpenIndiana 2025.06)


Cross Compiling
---------------

For target platforms other than Android, see section "CROSS COMPILING WITH
CMAKE" below.  For Android, the current DCMTK release can be cross-compiled
targeting the following platform:

   Android         / arm64        / Clang 18.0.1      (API 35, ABI arm64-v8a)

Cross compiling support with running configuration and unit tests is provided
using CMake and requires the use of the Android emulator or Wine when targeting
Android or Windows respectively.  Other versions of Android may also work,
but the above mentioned one is currently the only one that is being
regularly tested.


Other Platforms
---------------

The previous release DCMTK 3.6.9 was also tested on the following platforms
that may still work, but were not tested again for this release:

   Android         / arm64        / GNU gcc 12.2.0    (API 24, ABI arm64-v8a)
   FreeBSD 14.1    / amd64|x86_64 / Clang 18.1.5
   Linux 4.19.0    / ppc64le      / IBM XL C/C++ 16.1.1 Community
   Linux 5.14.0    / amd64|x86_64 / GNU gcc 11.4.1    (AlmaLinux 9.4)
   Linux 6.1.0     / Intel x86    / Clang 14.0.6      (Debian 12)
   Linux 6.1.0     / Intel x86    / GNU gcc 12.2.0    (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / Clang 14.0.6      (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / GNU gcc 12.2.0    (Debian 12)
   Linux 6.1.0     / amd64|x86_64 / GNU gcc 13.2.1    (Alpine 3.20 musl libc)
   Linux 6.8.0     / amd64|x86_64 / Clang 18.1.3      (Ubuntu 24.04.1 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 10.5.0    (Ubuntu 24.04.1 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 11.4.0    (Ubuntu 24.04.1 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 12.3.0    (Ubuntu 24.04.1 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 13.2.0    (Ubuntu 24.04.1 LTS)
   Linux 6.8.0     / amd64|x86_64 / GNU gcc 14.2.0    (Ubuntu 24.04.1 LTS)
   Linux 6.11.0    / amd64|x86_64 / GNU gcc 14.2.0    (Ubuntu 24.10)
   MacOS X 13.4.1  / amd64|x86_64 / Apple Clang 14.0.3
   MacOS X 13.4.1  / amd64|x86_64 / GNU gcc 13.1.0
   MacOS X 13.4.1  / arm64        / Apple Clang 15.0.0
   NetBSD 10.0     / amd64|x86_64 / Clang 16.0.6
   NetBSD 10.0     / amd64|x86_64 / GNU gcc 10.5.0
   OpenBSD 7.5     / amd64|x86_64 / Clang 16.0.6
   OpenIndiana     / amd64|x86_64 / GNU gcc 13.2.0    (OpenIndiana 2023.10)

The previous release DCMTK 3.6.8 was also tested on the following platforms
that may still work, but were not tested again for this release:

   FreeBSD 13.2    / amd64|x86_64 / Clang 14.0.5
   Linux 3.10.0    / amd64|x86_64 / Clang 3.4.2       (CentOS 7.9)
   Linux 3.10.0    / amd64|x86_64 / GNU gcc 4.8.5     (CentOS 7.9)
   Linux 4.19.0    / amd64|x86_64 / GNU 12.2.1        (Alpine 3.15.0 musl libc)
   Linux 5.10.0    / Intel x86    / Clang 11.0.1      (Debian 11)
   Linux 5.10.0    / amd64|x86_64 / GNU gcc 10.2.1    (Debian 11)
   Linux 5.15.0    / amd64|x86_64 / Clang 13.0.1      (Ubuntu 22.04.3 LTS)
   Linux 5.15.0    / amd64|x86_64 / Clang 14.0.0      (Ubuntu 22.04.3 LTS)
   Linux 5.15.0    / amd64|x86_64 / GNU gcc 9.5.0     (Ubuntu 22.04.3 LTS)
   Linux 5.15.0    / amd64|x86_64 / GNU gcc 10.5.0    (Ubuntu 22.04.3 LTS)
   Linux 5.15.0    / amd64|x86_64 / GNU gcc 11.4.0    (Ubuntu 22.04.3 LTS)
   Linux 5.15.0    / amd64|x86_64 / GNU gcc 12.3.0    (Ubuntu 22.04.3 LTS)
   Linux 6.2.0     / amd64|x86_64 / clang 15.07       (Ubuntu 23.04)
   Linux 6.2.0     / amd64|x86_64 / gcc 12.3.0        (Ubuntu 23.04)
   NetBSD 9.3      / amd64|x86_64 / Clang 13.0.1
   NetBSD 9.3      / amd64|x86_64 / GNU gcc 7.5.0
   OpenBSD 7.3     / amd64|x86_64 / Clang 13.0.0
   OpenIndiana     / amd64|x86_64 / GNU gcc 10.3.0    (OpenIndiana 2021.10)
   Windows 10      / Intel x86    / MinGW Clang 15.0.7 (i686-w64-windows-gnu)
   Windows 10      / Intel x86    / MinGW gcc 12.2.0 (i686-w64-mingw32)
   Windows 10      / amd64|x86_64 / MinGW Clang 15.0.7 (x86_64-w64-windows-gnu)
   Windows 10      / amd64|x86_64 / MinGW gcc 12.2.0 (x86_64-w64-mingw32)
   Windows 7       / Intel x86    / Microsoft Visual C++ 2015 Community (VS 14)
   Windows 7       / Intel x86    / Microsoft Visual C++ 2017 Community (VS 15)
   Windows 7       / Intel x86    / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 7       / Intel x86    / MinGW gcc 9.2.0 (i686-w64-mingw32)
   Windows 7       / amd64|x86_64 / Microsoft Visual C++ 2015 Community (VS 14)
   Windows 7       / amd64|x86_64 / Microsoft Visual C++ 2017 Community (VS 15)
   Windows 7       / amd64|x86_64 / Microsoft Visual C++ 2019 Community (VS 16)
   Windows 7       / amd64|x86_64 / MinGW gcc 9.2.0 (x86_64-w64-mingw32)


Earlier releases of the DCMTK are known to also compile on further platforms,
which are not available to us for testing purposes any more, e.g. AIX, HP-UX,
IRIX, NeXTStep, OSF/1, QNX, Solaris/SunOS, Ultrix.  Also the Intel C++ Compiler
and other compilers might still work, but we haven't tested them this time.


THIRD-PARTY LIBRARIES
=====================

DCMTK can make use of the following third-party libraries:

- OpenSSL: Support for encryption and signatures
- zlib:    Support for Deflated transfer syntax
- libtiff: Support for creating TIFF images
- libpng:  Support for creating PNG images
- libxml2: Support for converting XML to DICOM
- libwrap: Support for network access control (TCP wrapper)
- For character set support, either one of:
  - oficonv (default, and built into DCMTK)
  - libiconv (GNU, standalone or provided by the C standard library)

Further information about each of the libraries can be found below.  These
libraries are usually detected automatically on Unix-like operating systems
during build system configuration (CMake or Autoconf).  On Windows, some
build settings are usually required, see section "BUILDING" for details.


OpenSSL Support
---------------

DCMTK supports encrypted network transmissions using the Transport Layer
Security (TLS) protocol as defined in DICOM part 15, as well as digital
signatures.  DCMTK relies on the OpenSSL toolkit (www.openssl.org) for the
underlying cryptographic routines and the TLS protocol implementation.

This release of DCMTK requires OpenSSL release 1.1.1 or newer.  Users should
make sure that the most recent OpenSSL patch level is applied.  This release of
DCMTK is known to compile with OpenSSL releases 1.1.1 as well as 3.0.x to 3.6.x.

When using CMake, if support for security enhancements is desired, a compiled
version of the OpenSSL libraries and include files must be available during
compilation of DCMTK.  By default, DCMTK checks whether OpenSSL is installed
and enables support automatically if present.  By default, DCMTK checks the
standard paths on Unix platforms.  For Windows platforms, check the discussion
on CMake below.


KNOWN ISSUES RELATED TO OPENSSL

The ABI of various DCMTK libraries changes when DCMTK is built with or without
OpenSSL.  This may result in hard to locate bugs, e.g. when using a command
line tool that depends on one of those libraries while mixing a non-OpenSSL
build with an OpenSSL-enabled build of DCMTK (for example, when installing an
OpenSSL-enabled DCMTK on top of a DCMTK installation without OpenSSL support).
We have introduced a CMake variable called "DCMTK_TLS_LIBRARY_POSTFIX" as a
workaround.  If you plan on mixing OpenSSL and non-OpenSSL enabled builds (or
can't be sure that your builds won't be mixed by somebody else), we suggest
setting "DCMTK_TLS_LIBRARY_POSTFIX" to some different string for the different
builds (e.g. an empty string for the non-OpenSSL build and "-openssl" for the
other).  This way, all affected libraries will be named including the chosen
postfix, effectively preventing the unintended mixing and, therefore, preventing
the bugs.


Zlib Support
------------

DCMTK supports the "Deflated Explicit VR Little Endian" Transfer Syntax, i.e.
ZIP-compressed network transmission and media storage.  DCMTK relies on the
zlib toolkit (www.zlib.org) for the underlying compression routines.  This
release of DCMTK is known to compile with zlib releases 1.2.13 to 1.3.1,
although other releases may work as well.

When using CMake, a compiled version of the zlib libraries and include files
must be available during compilation of DCMTK.  See discussion on CMake below.


Libtiff Support
---------------

DCMTK supports the conversion of DICOM images to TIFF.  DCMTK relies on the
libtiff toolkit (www.libtiff.org) for this purpose.  This release of DCMTK is
known to compile with libtiff release 4.7.1, although other releases
may work as well.

When using CMake, a compiled version of the libtiff libraries and include files
must be available during compilation of DCMTK.  See discussion on CMake below.


Libpng Support
--------------

DCMTK supports the conversion of DICOM images to PNG.  DCMTK relies on the
libpng toolkit (www.libpng.org) for this purpose.  This release of DCMTK is
known to compile with libpng releases 1.6.47 to 1.6.51, although other releases
may work as well.

When using CMake, a compiled version of the libpng libraries and include files
must be available during compilation of DCMTK.  See discussion on CMake below.


Libxml2 Support
---------------

DCMTK supports the conversion of XML documents to DICOM files.  DCMTK relies on
the libxml2 toolkit (www.libxml.org) for this purpose.  This release of DCMTK
is known to compile with libxml2 releases 2.13.9 to 2.15.1, although other
releases may work as well.

When using CMake, if support for XML import is desired, a compiled version of
the libxml2 (and possibly iconv) libraries and include files must be available
during compilation of DCMTK.  See discussion on CMake below.


TCP Wrapper (libwrap) Support
-----------------------------

DCMTK supports Wietse Venema's TCP wrappers library (libwrap), which is freely
available for most Unix platforms and part of the default installation of most
recent Linux distributions.  This library allows for enforcing host-based
access control via the "/etc/hosts.deny" and "/etc/hosts.allow" configuration
files.  See "hosts_access(5)" man page for details.

When using CMake, if support for TCP wrappers is desired, a compiled version of
the libwrap library and include file "<tcpd.h>" must be available during
compilation of DCMTK.  See discussion on CMake below.

Since DCMTK uses the TCP wrappers from C++ code, an ANSI C compatible header
file "<tcpd.h>" is required.  The official release 7.6 of the TCP wrappers
library is not ANSI C compatible and does not work with DCMTK (i.e. will not be
recognized by DCMTK's configure script).  However, many current Linux and BSD
distributions ship with an ANSI C compatible header file.


Character Set Conversion Support
--------------------------------

DCMTK supports the conversion between different character encodings, e.g. UTF-8
and ISO Latin-1.  In DCMTK 3.6.8 and newer, three implementations of character
set conversion can be used:

- oficonv, a DCMTK module based on the Citrus iconv code in FreeBSD
- GNU libiconv
- iconv support provided by the C standard library

DCMTK selects the built-in module oficonv by default.  Other implementations
can be activated by the user via the "--enable-charconv" argument (Autoconf)
or "DCMTK_ENABLE_CHARSET_CONVERSION" (CMake).  Selecting an implementation
that is not available will be ignored, i.e. the user's choice will be
overridden.

The exact values that can be chosen for "--enable-charconv" and
DCMTK_ENABLE_CHARSET_CONVERSION are:
- "oficonv" (default)
- "libiconv"
- "stdlibc" (for DCMTK_ENABLE_CHARSET_CONVERSION: "stdlibc (iconv)")


LIBICONV SUPPORT

The libiconv toolkit (www.gnu.org/software/libiconv/) may be used as DCMTK's
underlying character set conversion implementation.  This release of DCMTK is
known to compile with the libiconv release 1.17, although other releases may
work as well.

When using CMake, a compiled version of the libiconv and libcharset libraries
and include files must be available during compilation of DCMTK.  See discussion
on CMake below.


SUPPORT FOR ICONV PROVIDED IN THE C STANDARD LIBRARY

DCMTK allows for using the iconv implementation provided as part of the C
standard library on some platforms.  Building DCMTK with this implementation may
be easier and reduce additional runtime dependencies, but this option should be
used with caution: the iconv implementations from different C standard libraries
may vary with regard to the supported character sets and functionalities.

If possible, the built-in oficonv implementation should be preferred.  Most
importantly, some iconv implementations provided by the C standard library do
not support conversion to whatever character set the terminal is currently
using, which we consider essential and, therefore, strongly suggest not to use
those implementations (there is a new configure test for the issue, which allows
for querying support for this on API level).


KNOWN ISSUES

If both the iconv implementation from the C standard library and the libiconv
are available in the default search paths, the wrong "<iconv.h>" file might be
included independently from the user's choice, i.e. "--enable-charconv" or
"DCMTK_ENABLE_CHARSET_CONVERSION".

DCMTK currently has no mechanism to force including a certain "<iconv.h>"
instead, so this has to be achieved by manually modifying the include paths
and/or DCMTK's code.  Some platforms (e.g. Arch Linux) even rename the
"<iconv.h>" file provided as part of libiconv to "<libiconv.h>" or the like to
avoid name collisions.  In this case, the user has to modify DCMTK's source code
to include the correct file, since we currently don't provide a configuration
test for it.


USING THE NATIVE STL
====================

DCMTK can be configured to use the STL (Standard Template Library) features
provided by the compiler / runtime environment instead of its own fallback
implementations that are used by default.

This can be achieved with the "--enable-stl" argument (Autoconf) or by setting
"DCMTK_ENABLE_STL" to "ON" (CMake).  This will, however, not forcibly enable
using the native STL features but instead trigger running several configuration
tests for detecting whether the individual features work as expected/required
by DCMTK.  It is for example known that "std::error_code" is not implemented
correctly in some versions of Visual Studio.

It is furthermore possible to enable or disable individual STL features
independently of the setting provided by "--enable-stl" or "DCMTK_ENABLE_STL"
respectively: use "--enable-stl-<feature>" or "--disable-stl-<feature>", or
set "DCMTK_ENABLE_STL_<FEATURE>" to "ON" or "OFF" as appropriate, e.g.
"--disable-stl-vector" or "-DDCMTK_ENABLE_STL_STRING=ON".


SUPPORT FOR MODERN C++ STANDARDS
================================

DCMTK can be configured to use several features of modern C++ standards (e.g.
C++11 move semantics, variadic templates and the like) instead of its own
workarounds and fallback implementations.  This can be achieved using the CMake
variable "CMAKE_CXX_STANDARD".

By default, DCMTK will compile with "CMAKE_CXX_STANDARD" set to "11" (CXX11).
The user can choose to build with a newer C++ standard by setting
"CMAKE_CXX_STANDARD" accordingly.  The following versions are supported:

- 11 (CXX11)
- 14 (CXX14)
- 17 (CXX17)
- 20 (CXX20)

Compilation of DCMTK with C++98 is deprecated.  In this release, it can be
enabled by setting "CMAKE_CXX_STANDARD=98" and "DCMTK_PERMIT_CXX98=ON", but
support for C++ releases before C++11 will be removed in future versions
of DCMTK.

Using C++11 or later will change some parts of DCMTK's API, so a C++11 build of
DCMTK is potentially incompatible with a classic (C++98) build of DCMTK.  This
setting is, therefore, stored in "config/include/dcmtk/config/osconfig.h" and
verified when compiling DCMTK itself or any program that includes it.

Having "CMAKE_CXX_STANDARD" set to "11" (or some newer C++ standard) will not
forcibly enable DCMTK to use the respective features but instead trigger running
some configuration tests and only truly enable the features that are really
supported (e.g. "std::error_code" is still not implemented as intended on newer
versions of Visual Studio, so we keep using DCMTK's own implementation there).

Please note that this setting does not depend on enabling the STL features, but
not all combinations (e.g. enabling C++11 but disabling "std::string") may work.


BUILDING
========

CMake is now the default tool for configuring a DCMTK build.  CMake is a
cross-platform, open-source make system which can be used to control the
software compilation process using simple configuration files.  CMake can be
obtained free of charge from https://cmake.org/.  For configuring the DCMTK,
the toolkit contains corresponding "CMakeLists.txt" files in all necessary
directories.  In detail, these "CMakeLists.txt" files will serve as an input to
CMake which will generate suitable build files for all of DCMTK's projects from
these files.

DCMTK 3.7.0 requires CMake version 3.7.0 or later.  We recommend using the
latest stable release of CMake (currently version 4.2.0) since newer versions
of CMake often provide better output in case of errors and are generally easier
to use (for example, by providing better support for detecting the availability
of third-party libraries).  If possible, use the CMake version your operating
system provides with its package manager.

More info about building the DCMTK with CMake can be found in DCMTK's wiki:

  https://support.dcmtk.org/wiki/dcmtk/howto/cmakeconfiguration

CMake and shared libraries
--------------------------

The CMake build system allows for building shared libraries instead of static
libraries.  On Windows systems, these are dynamic link libraries (.dll).
On Unix systems, these are shared objects (.so).  To enable this, set the
"BUILD_SHARED_LIBS" option to "ON".

Additionally, it is possible to produce a single shared library for the whole
toolkit.  This mode is controlled by the "BUILD_SINGLE_SHARED_LIBRARY" option.
If you don't want the whole toolkit in a single shared library, the
"DCMTK_MODULES" cache variable can be modified to select a subset of the
available modules.  Please note that this option is marked as advanced and thus
is hidden by default.  Also, when building a single shared library, applications
and tests cannot be built.

Default value for CMAKE_BUILD_TYPE
----------------------------------

"CMAKE_BUILD_TYPE" is set to value "Release" if none is specified by the
selected build file generator.  For those generators that support multiple
configuration types (e.g. Debug, Release), "CMAKE_CONFIGURATION_TYPES" holds
possible values.  For other generators, this value is empty, and for those
generators the build type is fixated by CMake and cannot be changed otherwise.
Please note that Visual Studio ignores "CMAKE_BUILD_TYPE" and always starts off
using "Debug", so you should best change it to "Release" manually before
starting the build process.

To disable the "CMAKE_BUILD_TYPE" default value, set "CMAKE_BUILD_TYPE" to value
"None" during CMake configuration, e.g. use "-DCMAKE_BUILD_TYPE:STRING=None"
on the command line.  This may be useful if the compiler flags should be
controlled manually (e.g. as defined in environment variables like "CXXFLAGS")
and no CMake defaults related to the selected configuration type kick in.

DCMTKConfig.cmake AND DCMTKTargets.cmake
----------------------------------------

CMake permits to write files that describe the DCMTK build configuration
("DCMTKConfig.cmake") as well as all targets (executables and libraries) that
have been produced ("DCMTKTargets.cmake").  Those files can be utilized by
external projects by using CMake's "find_package()" mechanism in "CONFIG" mode
in order to adapt their own build configuration, and directly make use of all
available target libraries and executables.

These files are written during installation to the installation directory's
subfolder "/cmake" on Windows systems, and "/lib/cmake/dcmtk" on Unix-like
systems.  Additionally, these files are written to the main directory of
CMake's build tree during the build, with all content (e.g. the include
paths within "DCMTKConfig.cmake") pointing to the correct values for the build
tree.  Thus, even a DCMTK build tree can be used by external projects that
process these two files.

Microsoft Windows with CMake
----------------------------

Using CMake is the only supported way to compile DCMTK for Windows.  For being
able to do so, perform the following steps to install CMake on your machine:

1. Go to https://cmake.org/ to download the latest release version of CMake
   for Windows.
2. Execute the file which was downloaded to install CMake on your machine.
   Follow all install instructions appropriately.

In order to manually configure the support for the above mentioned external
libraries (OpenSSL, zlib, libtiff, libpng, libxml2 and libiconv), there are
basically two ways:

a. Using the "DCMTK_SUPPORT_LIBRARIES_DIR" setting:

On Windows, users sometimes consider these third-party libraries hard to
compile and integrate with DCMTK.  Therefore, the DCMTK download page offers a
package with pre-built versions of these libraries ("support libraries") for
Windows.  When this library package should be used, there is a single CMake
variable ("DCMTK_SUPPORT_LIBRARIES_DIR") that can be assigned to the main
directory of the extracted third-party package.  In that case, CMake will find
and make available all third-party libraries to the DCMTK build and no further
steps are necessary.

If this is not desired, e.g. since a user wants to use different versions or
builds of these libraries, the libraries can be configured manually.  The
following sections include some guidance how to accomplish that for each
third-party library.

b. Using the manual "per-library" configuration switches:

Through CMake, perform the following steps:

1. Go to Start -> Programs -> CMake -> "CMake" or "CMake (cmake-gui)" to start
   the CMake utility through which the configuration can be done.
2. In the entry field "Where is the source code:" enter the directory in which
   the DCMTK source code resides, e.g. "C:\dcmtk-3.7.0".
3. In the entry field "Where to build the binaries:" enter the directory in
   which the libraries and binaries are to be built, e.g. "C:\dcmtk-msvc16".
4. In the combobox "Build for:" or "Specify the generator for this project:"
   select the corresponding development environment that shall be used to
   compile the DCMTK (e.g. "Visual Studio 16 2019 Win64").
5. Go "Configure".  (CMake will look for a corresponding compiler, read in all
   of DCMTK's "CMakeLists.txt" files and perform some tests.  The variables in
   the tabular area will be displayed in red.  These variables can now be set
   in order to turn the support for any of the external libraries on or off.)
6. Make the corresponding configurations in CMake's user interface.  For
   example, in order to turn on libxml2 support, set the value of variable
   "DCMTK_WITH_XML" to "ON" and set the value of variable "WITH_LIBXMLINC" to
   the path where the include files and libraries of libxml2 can be found, e.g.
   "C:\libxml2-2.15.1".  The support of all other external libraries can be
   turned on in a similar way:

     libpng support:
       set "DCMTK_WITH_PNG" to "ON" and
       set "WITH_LIBPNGINC" e.g. to "C:\libpng-1.6.51"

     libtiff support:
       set "DCMTK_WITH_TIFF" to "ON" and
       set "WITH_LIBTIFFINC" e.g. to "C:\libtiff-4.7.1"

     OpenSSL support:
       set "DCMTK_WITH_OPENSSL" to "ON" and
       set "WITH_OPENSSLINC" e.g. to "C:\openssl-3.6.0"

     zlib support:
       set "DCMTK_WITH_ZLIB" to "ON" and
       set "WITH_ZLIBINC" e.g. to "C:\zlib-1.3.1"

   In order to turn the support of a certain external library off, set the
   value of the corresponding variable ("DCMTK_WITH_XML", "DCMTK_WITH_PNG",
   "DCMTK_WITH_TIFF", "DCMTK_WITH_OPENSSL" or "DCMTK_WITH_ZLIB") to "OFF".

   (Please note that the include files of all external libraries are always
   expected in a directory named "include" below the directory that is
   specified in "WITH_LIBXMLINC", "WITH_LIBPNGINC", "WITH_LIBTIFFINC",
   "WITH_OPENSSLINC" or "WITH_ZLIBINC".)

   (Please note also that the library files of all external libraries are always
   expected in directory named "lib" below the directory that is specified in
   "WITH_LIBXMLINC", "WITH_LIBPNGINC", "WITH_LIBTIFFINC", "WITH_OPENSSLINC"
   or "WITH_ZLIBINC".  Moreover, note that the following
   filenames must be used for the corresponding lib files:

     libxml2:
       "iconv_d.lib"       - debug version (* See note below)
       "iconv_o.lib"       - release version (optimized) (* See note below)
       "libxml2_d.lib"     - debug version
       "libxml2_o.lib"     - release version (optimized)

     libpng:
       "libpng_d.lib"      - debug version
       "libpng_o.lib"      - release version (optimized)

     libtiff:
       "libtiff_d.lib"     - debug version
       "libtiff_o.lib"     - release version (optimized)

     openssl:
       "dcmtkcrypto_d.lib" - debug version
       "dcmtkcrypto_o.lib" - release version (optimized)
       "dcmtkssl_d.lib"    - debug version
       "dcmtkssl_o.lib"    - release version (optimized)

     zlib:
       "zlib_d.lib"        - debug version
       "zlib_o.lib"        - release version (optimized)

   The debug and release versions of all libraries must be compiled with the
   same runtime library dependency as DCMTK (i.e., /MT[d] or /MD[d]).
   By default, DCMTK is compiled with /MTd for Debug and /MT for Release mode
   unless the CMake variables "DCMTK_COMPILE_WIN32_MULTITHREADED_DLL" or
   "BUILD_SHARED_LIBS" (see below) are set to true, in which case DCMTK is
   compiled with /MDd for Debug and /MD for Release mode.

   Precompiled versions of all libraries can be downloaded from
   https://dcmtk.org/develop/#lib-win .


   In the CMake GUI, there are a few more settings that can be modified
   to affect the way DCMTK is compiled.  The most important of these are:

    - DCMTK_OVERWRITE_WIN32_COMPILER_FLAGS: By default, DCMTK will compile
      using the default compiler options selected by CMake.  When this macro
      is enabled, these default options are modified based on the value
      of the "DCMTK_COMPILE_WIN32_MULTITHREADED_DLL" setting (see below).
      Default: ON.
    - DCMTK_COMPILE_WIN32_MULTITHREADED_DLL: Controls the Windows build
      model.  When this setting is "ON", DCMTK is compiled with the
      "Multithreaded DLL" build model (/MD or /MDd); when the setting is
      "OFF", DCMTK is compiled with the "Multithreaded" build model
      (/MT or /MTd).  This setting is ignored unless the
      "DCMTK_OVERWRITE_WIN32_COMPILER_FLAGS" option is "ON".  Default: OFF.
    - BUILD_SHARED_LIBS: Build the DCMTK libraries as shared libraries.
      This setting overrides the value of the options
      "DCMTK_OVERWRITE_WIN32_COMPILER_FLAGS" and
      "DCMTK_COMPILE_WIN32_MULTITHREADED_DLL", which are both set to "ON".
      Default: OFF.
    - BUILD_SINGLE_SHARED_LIBRARY: Build a single shared library for the
      whole toolkit.  This setting overrides the value of the option
      "BUILD_SHARED_LIBS", which is set to "ON".  Default: OFF.
    - DCMTK_USE_WIN32_PROGRAMDATA: An experimental setting that will cause
      data files (such as the DICOM dictionary "dicom.dic" and the oficonv
      character set mapping tables) and configuration files to be installed
      and expected in a subdirectory of the "ProgramData" directory.

7. Go "Configure" a second time.  (CMake will adjust the configuration
   according to the displayed specifications.)
8. Go "OK" or "Generate".  (CMake will generate new project files in the
   corresponding directories.  These files will be adjusted according to the
   displayed specifications, i.e. support for the external libraries will be
   turned on or off.)

Having performed these steps, the Microsoft Visual Studio IDE can be started,
DCMTK's workspace file can be opened, and one or more of DCMTK's subprojects
can be built.  In case you want to build all libraries and applications, mark
the predefined target "ALL_BUILD" and build it.  The "INSTALL" target installs
the executables, libraries, include, support and documentation files to the
directory specified by the variable "CMAKE_INSTALL_PREFIX" (very similar to
"make install-all" on Unix systems).

Compilation and installation of the various command line applications
(including the test programs) can be disabled by setting the "BUILD_APPS"
option to "OFF" before configuring and generating the project files.  By
default, all command line applications are built and installed.

Please note that other Windows compilers, e.g. Borland C++ Builder, are
currently not actively supported.  However, they may work.

Known limitations of DCMTK on the Windows platform:

- The dcmqrscp tool cannot spark multiple processes.  Every association must be
  handled completely before a new association is possible.

Unix with CMake
---------------

One key difference when using CMake for building on Unix-like systems is that we
use the "find_package()" mechanism for all external libraries.  Most Unix-like
systems provide a package manager or even if not at least have a consistent
approach for where the libraries and include files are installed such that the
CMake "find_package()" mechanism typically finds them out of the box.

If that does not work or you want to use a different version of a library than
the one in the default search paths, you should look at the documentation of
the respective "find_package()" module to find out which variables need to be
modified, e.g. "FindZLIB" to control which version of the zlib will be used,
see: https://cmake.org/cmake/help/latest/module/FindZLIB.html .

The typical way to build DCMTK on Unix-like systems with CMake is as follows
(if not using the GUI, in that case look at the description for Windows above):

    mkdir dcmtk-3.7.0-build
    cd dcmtk-3.7.0-build
    cmake ../dcmtk-3.7.0
    make -j8
    make DESTDIR=../dcmtk-3.7.0-install install

The above commands assume that the DCMTK source code was extracted to the
current working directory into a folder named "dcmtk-3.7.0".  DCMTK will be
configured using CMake with the default options, detecting and including all
available support libraries and then compiled using eight CPU cores
("make -j8", adjust as needed).  The result will be installed to the directory
"dcmtk-3.7.0-install" next to the source code directory.

If you want to modify your build configuration, like enabling or disabling some
features of DCMTK (e.g. PNG support), or if you need to modify the predefined
build variables, you can use the curses-based CMake configuration tool ccmake.
First, create the initial build setup (system check) and then call "ccmake":

    mkdir dcmtk-3.7.0-build
    cd dcmtk-3.7.0-build
    cmake ../dcmtk-3.7.0
    ccmake ../dcmtk-3.7.0

Now you can modify the configuration values.  Please see the help on the bottom
of the screen.  When finished, press "c" to generate a new build configuration,
then quit ccmake.  Now you can continue to build by calling "make" etc.

If you already know the variable names, types and values to set, you can skip
the ccmake step above and call "cmake" directly with the desired values set.
Example for a build with TCP wrapper disabled:

    mkdir dcmtk-3.7.0-build
    cd dcmtk-3.7.0-build
    cmake -DDCMTK_WITH_WRAP:BOOL=FALSE ../dcmtk-3.7.0
    ...

The format is "NAME:TYPE=VALUE".  Use ccmake to find out the variable names and
their types ("BOOL" with "TRUE"/"FALSE" or "STRING").  Some of the more
important variables are:

  - BUILD_APPS: Build the DCMTK command line tools? Default: ON.
  - BUILD_SHARED_LIBS: Build the DCMTK libraries as shared libraries?
    Default: OFF.
  - CMAKE_BUILD_TYPE: Debug or Release build.  Default: Release.
  - CMAKE_INSTALL_PREFIX: Installation prefix.  Default: "/usr/local".
  - DCMTK_DEFAULT_DICT: Activate the builtin, external or no DICOM data
    dictionary on DCMTK startup?  Default: builtin on Windows, external on
    Linux/Posix.
  - CMAKE_CXX_STANDARD: C++ language version to be used.  Default: 11.
  - DCMTK_ENABLE_STL: Replace DCMTK's OFString, OFList, OFVector etc. by the
    STL classes std::string, std::list, std::vector etc.  Default: OFF.
  - OPENSSL_ROOT_DIR: Directory where OpenSSL is installed.  Default: search
    in standard directories for headers and libraries.


HTML DOCUMENTATION AND MAN PAGES
================================

Most DCMTK modules have been documented with Doxygen (www.doxygen.org), a free
source code documentation system similar to Javadoc.  Unix users who have
Doxygen installed can create a hypertext documentation with "make html" in the
"dcmtk-3.7.0" or "doxygen" directory; Windows and other CMake users should
build the "DOXYGEN" target.  A project file for Microsoft's HTML Help Workshop
can also be generated allowing to create a single CHM file (compressed HTML)
from the documentation.  Other output formats (e.g. LaTeX) can be enabled by
changing the configuration file in the "doxygen" directory.

Currently, dcmapps, dcmect, dcmfg, dcmiod, dcmimage, dcmimgle, dcmjpeg, dcmpmap,
dcmpstat, dcmrt, dcmseg, dcmsign, dcmsr, dcmtls, dcmtract, dcmwlm, oficonv and
ofstd are completely documented; dcmdata, dcmjpls, dcmnet, dcmqrdb and oflog
are almost completely documented.  See FAQ entry: "Where is rest of the
documentation?"

On Unix platforms, man pages for all command line tools are installed during
the "make install" step.  In order to use them, just add the directory (e.g.
"/usr/local/share/man") to the "MANPATH" environment variable and call
"man dcmdump" to check whether it works.

In order to generate plain text files from the man pages call "make text" in
the "doxygen" directory.  The output files are stored in "doxygen/man2text".


DICOM DATA DICTIONARY
=====================

Almost all DCMTK tools and libraries require the so-called DICOM data dictionary
(i.e. information from part 6 of the DICOM standard) to be available in order
to map the Attribute Tags to their associated Value Representation (VR), Value
Multiplicity (VM) and Attribute name (official keyword).  The data dictionary
can either be loaded from file (default on Unix systems) or be built into the
respective tool / dcmdata library (default on Windows systems).  The default
behavior can be changed using appropriate configuration options.

Details can be found in the documentation file at "dcmdata/docs/datadict.txt"
(or "/usr/local/share/doc/dcmtk-<VERSION>/datadict.txt").


OFICONV DATA FILES
==================

When oficonv is used to implement character set conversion (which is the
default, starting with DCMTK 3.6.8), then a set of binary data files containing
mapping tables are used during the conversion process.  By default, these are
installed and expected in DCMTK's data path ("/usr/local/share/dcmtk-<VERSION>/
data") in the subdirectories "esdb" and "csmapper".  The data path can be
overridden at runtime by setting the environment variable "DCMICONVPATH" to
point to a different directory.

It is possible to embed the mapping tables into the oficonv library, in which
case no external files are needed at runtime.  This can be enabled by setting
the CMake variable "DCMTK_ENABLE_BUILTIN_OFICONV_DATA" to "ON".  This behavior
is enabled by default when DCMTK is compiled into shared libraries (option
"BUILD_SHARED_LIBS" set to "ON"), and disabled by default otherwise.  Note that
when using static libraries, the built-in mapping tables will increase the size
of each executable by approx. 4 MBytes.

The "DCMICONVPATH" environment variable is respected even when built-in mapping
tables are available.  In this case, the files referred to by "DCMICONVPATH"
override the built-in files, unless "DCMICONVPATH" points to DCMTK's default
data path.


COMPILE-TIME FLAGS AND ENVIRONMENT VARIABLES
============================================

The behavior of several DCMTK tools and libraries can be modified by a number
of compile-time flags (macros).  Those macros that are not automatically
handled by the configure mechanism are documented in "config/docs/macros.txt"
(or "/usr/local/share/doc/dcmtk-<VERSION>/macros.txt").

There is also a number of environment variables that affect DCMTK's behavior.
These are documented in "config/docs/envvars.txt" (or "/usr/local/share/doc/
dcmtk-<VERSION>/envvars.txt").


RUNNING THE TEST SUITE
======================

DCMTK comes with a test suite that verifies that the toolkit works as expected.
The tests are contained in a module's "tests" subdirectory.  Some tests are
marked as exhaustive and are only run if explicitly enabled, see below.

When using Autoconf for building DCMTK, all tests can be run via "make check".
If a test fails, make will stop and the failure reason of the test that failed
should be visible.  Additionally, you may run the exhaustive unit tests by
typing "make check-exhaustive".

You can also run the test suite with CMake.  However, the steps needed for
running the test suite depend on the generator used.  The Visual Studio
generators will create a "RUN_TESTS" target.  Building this project will call
CTest and run all tests.  When using the Makefile generator, "make test" runs
the test suite.  Additionally, you may run the exhaustive unit tests by typing
"make test-exhaustive".  Other generators should use a similar approach.

For closer inspection, individual tests can be run directly.  The Makefiles
will build the test runner for each module as "<module>/tests/tests".  CMake
will add the module name as a prefix to this file's name, e.g. "ofstd_tests".
For more information, call this program with the "--help" option.


CROSS COMPILING WITH CMAKE
==========================

The main challenge when cross-compiling DCMTK is that some of the feature tests
performed by CMake require certain small test programs to be compiled and run,
which does not work in a cross-compilation setting.  Starting with DCMTK 3.6.8,
basic support for cross-compilation has been added.  This can be enabled by
setting the CMake variable "DCMTK_NO_TRY_RUN":

  cmake -DDCMTK_NO_TRY_RUN:BOOL=TRUE

In this case, CMake expects all test results that are normally achieved by
executing certain test programs to be provided by the user on the command line.
In detail, these are the variables that need to be provided:

  The following variables are only used when compiling with libiconv support
  and can otherwise be set to default values:
  - DCMTK_ICONV_FLAGS_ANALYZED: should always be set to TRUE
  - DCMTK_FIXED_ICONV_CONVERSION_FLAGS: The output printed by the test program
    "config/tests/iconv.cc", when run on the target platform.  This value is
    only used when compiling with old libiconv versions (older than libiconv
    1.8) and determines the iconv behavior when encountering illegal byte
    sequences during a character set conversion.  Possible values are:
    - "AbortTranscodingOnIllegalSequence" (use as default)
    - "DiscardIllegalSequences"
  - DCMTK_STDLIBC_ICONV_HAS_DEFAULT_ENCODING: true if the test program
    "config/tests/lciconv.cc" exits with a return code of zero, false otherwise.
    This test determines if libiconv has a default encoding, i.e. if
    "iconv_open()" accepts "" as an argument.  Use FALSE as default.

For further information on cross-compiling DCMTK, see:
https://support.dcmtk.org/redmine/projects/dcmtk/wiki/Cross_Compiling


BUILDING (Unix with Autoconf)
=============================

Configuring a DCMTK build with GNU Autoconf has been deprecated and will be
removed in a future release.  In the current release, the "configure" script in
DCMTK's top-level main directory has been removed as the final warning for users
of the Autoconf toolchain.  If you prefer to build DCMTK with Autoconf, however,
this is still possible.  Perform the following steps from the top-level
("dcmtk-3.7.0") directory to compile and install the software:

Step 0:
    cd config
    ./rootconf
    cd ..

Step 0 creates the configure script in DCMTK's top-level directory.

Step 1:
    ./configure --ignore-deprecation

Step 1 executes the configure scripts in each subdirectory.  First, the system
capabilities are examined and then Makefiles are generated.  By default,
executables and other files will be installed (in Step 3) in the directory
"/usr/local" in the corresponding subdirectories.  If you wish to use another
install prefix you can use the "--prefix=<path>" option to configure.  E.g., if
you wish to install underneath your home directory in "~/dicom" then you should
start configure as:

    ./configure --ignore-deprecation --prefix=$HOME/dicom

Step 1 is also the place where support for the external libraries can be enabled
or disabled.  By default, all libraries installed in the standard path are
enabled automatically.  Use the "--without-openssl" switch to disable OpenSSL
support.  The "--with-opensslinc" option allows for specifying the directory in
which OpenSSL is installed.  This is usually the directory that has been used as
"--prefix" when compiling and installing OpenSSL.

For example, if you wish to enable the security enhancements, and OpenSSL is
installed in "/usr/local/apps/openssl-3.6.0", you should start configure as:

    ./configure --ignore-deprecation
                --with-opensslinc=/usr/local/apps/openssl-3.6.0

Configure will assume that the OpenSSL include files are installed in
"/usr/local/apps/openssl-3.6.0/include" and will expect the library in
"/usr/local/apps/openssl-3.6.0/lib".  Appropriate options will be passed to
the compiler and the linker.

Support for zlib, libtiff, libpng, libxml2, libwrap, and/or libiconv can be
enabled in a similar way (in case these libraries are not installed in the
standard path), e.g.:

    ./configure --ignore-deprecation
                --with-libzlibinc=/usr/local/apps/zlib-1.3.1
                --with-libtiffinc=/usr/local/apps/libtiff-4.7.1
                --with-libpnginc=/usr/local/apps/libpng-1.6.51
                --with-libxmlinc=/usr/local/apps/libxml2-2.15.1
                --with-libwrapinc=/usr/local/apps/tcp_wrappers-7.6
                --with-libiconvinc=/usr/local/apps/libiconv-1.17

Different configure options can be combined in any order.  "configure --help"
will print a list of all existing configure options.  "configure --help=short"
will display only those options that are specific to the DCMTK.  Useful
configure options are:

  --enable-debug          compile with debug code, don't optimize
  --disable-debug         compile without debug code (default)
  --enable-threads=TYPE   compile with MT support (posix/solaris/auto=default)
  --disable-threads       compile without MT support
  --enable-lfs=TYPE       compile with LFS support (lfs/lfs64/auto=default)
  --disable-lfs           compile without LFS support
  --enable-default-dict=TYPE  enable default dictionary and specify type
                          (external=default/builtin)
  --disable-default-dict  disable default dictionary
  --enable-dcmdictpath    enable DCMDICTPATH environment variable (default)
  --disable-dcmdictpath   disable DCMDICTPATH environment variable
  --enable-private-tags   enable private tag dictionary
  --disable-private-tags  don't enable private tag dictionary (default)
  --disable-rpath         do not hardcode runtime library paths
  --enable-charconv=TYPE  enable character set conversion support
                          (libiconv/stdlibc/oficonv=default)
  --disable-charconv      disable character set conversion support
  --enable-cxx11          use C++11 (default)
  --disable-cxx11         do not use C++11
  --enable-stl            use C++ STL
  --disable-stl           do not use C++ STL (default)

Step 2:
    make all

Step 2 will build the libraries and executables.  If you run into problems see
the section "Solving configuration and compilation problems" below.

Step 3:
    make install

Step 3 will install the executables and some support files (data dictionary,
configuration and documentation files).  If you also wish to install the
libraries and include files then use "make install-lib".  For the HTML
documentation (see above) use "make install-html" (requires Doxygen to be
installed); "make install-all" installs all of the above.

In case the files should be installed in a temporary directory, e.g. in order
to create a distribution package, use "make install DESTDIR=<path>" to prepend
"<path>" to the installation directories specified for configure.

Step 4:
    make distclean

Step 4 will revert the source tree to the state prior to Step 1.  If you just
want to get rid of object files and local executables use "make clean" instead.

Note: In case you do not want to compile all modules, you can remove those
modules from the text file "config/modules" prior to Step 1 and execute the
following commands:

    cd config
    ./rootconf
    cd ..

This generates a new Makefile and configure script in the top-level toolkit
directory.

Solving configuration and compilation problems
----------------------------------------------

The configure script might not be able to guess the correct compiler and
compiler flags to use.  For example, we have noticed that use of the "-pedantic"
flag to the GNU C++ compiler causes compilation errors on some systems due to
system include files with incorrect ANSI function prototypes.

You can set environment variables to initialize configure before it is called
(before Step 1 above):

  Set environment variable "CC" to the name of your C compiler.
  Set environment variable "CFLAGS" to the compile flags of your C compiler.
  Set environment variable "CXX" to the name of your C++ compiler.
  Set environment variable "CXXFLAGS" to the compile flags of your C++ compiler.
  Set environment variable "LDFLAGS" to your linker flags.
  Set environment variable "CPPFLAGS" to you preprocessor flags.

You do not need to specify all the above environment variables since the
default settings are sensible for most Unix compilers.  Further influential
environment variables are listed in the output of "configure --help".

If the configure script fails you may have to change the configuration settings
in the "config" directory.  See the "config/docs" directory for more
information.

See also the FAQ at https://forum.dcmtk.org/faq for more hints.

---------

Have fun.

M. Eichelberg, J. Riesmeier, M. Onken, T. Xu, H. Roesen
DCMTK Development Team, Oldenburg, Germany.

Last revised: 2025-12-02 (Riesmeier)
