Dear maintainer,

Your package fails to build from source against opencv 5.0.0+dfsg-1~exp1,
currently in experimental.

OpenCV 5.0 renames its entire install tree from opencv4 to opencv5 and ships
no compatibility shims:

  * pkg-config: only /usr/lib/<triplet>/pkgconfig/opencv5.pc.  There is no
                opencv4.pc and no opencv.pc.
  * headers:    /usr/include/opencv5/opencv2/..., no /usr/include/opencv4.
  * cmake:      /usr/lib/<triplet>/cmake/opencv5/OpenCVConfig.cmake.  A bare
                find_package(OpenCV) still resolves, but a pinned version
                such as find_package(OpenCV 4.7) no longer matches.
  * modules:    libopencv-calib3d-dev is split into libopencv-calib-dev,
                libopencv-geometry-dev, libopencv-stereo-dev and
                libopencv-ptcloud-dev; libopencv-features2d-dev becomes
                libopencv-features-dev.  The CMake component names change
                with them (features2d -> features).
  * geometry:   the new geometry module is not only a piece of calib3d.  It
                also absorbs shape and contour functions that used to live
                in imgproc -- contourArea, arcLength, approxPolyDP,
                boundingRect, minAreaRect, convexHull and
                getPerspectiveTransform among them -- and opencv2/opencv.hpp
                does not pull in opencv2/geometry.hpp, so code that reached
                those through the umbrella header now needs an explicit
                include of opencv2/geometry.hpp.

In nomacs's case, ImageLounge/src/DkCore/DkImageStorage.h:41 includes the
legacy C-API header opencv2/imgproc/imgproc_c.h, which OpenCV 5 removes
outright rather than relocating it under opencv5/opencv2/imgproc/. That
header is pulled in, directly or via DkBaseViewPort.h, by at least
fifteen nomacsCore translation units, including DkImageStorage.cpp,
DkViewPort.cpp, DkToolbars.cpp, DkActionManager.cpp, DkBasicWidgets.cpp,
DkBaseViewPort.cpp, DkManipulators.cpp, DkThumbsWidgets.cpp,
DkMetaData.cpp, DkCentralWidget.cpp, DkNoMacs.cpp, DkImageLoader.cpp,
DkDialog.cpp, DkControlWidget.cpp, and DkImageContainer.cpp, all of which
fail with the same fatal error. The maintainer should drop the
imgproc_c.h include, use the C++ header opencv2/imgproc.hpp instead, and
port any remaining IplImage/CvMat-based calls in DkImageStorage.h to the
cv::Mat-based imgproc API.

The same source builds fine in the same chroot against the OpenCV 4.10
packages currently in unstable, so this is specific to OpenCV 5.

The relevant part of the build log follows; the full log is attached.

  [ 31%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkProcess.cpp.o
  [ 32%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkPluginManager.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 33%] Building CXX object CMakeFiles/nomacsCore.dir/src/DkCore/DkMath.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 35%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkBasicLoader.cpp.o
  [ 37%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkManipulatorsIpl.cpp.o
  [ 37%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkBasicWidgets.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 38%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkBatchInfo.cpp.o
  [ 39%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkManipulators.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 40%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkBaseViewPort.cpp.o
  [ 41%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkImageStorage.cpp.o
  [ 42%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkSettings.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 43%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkSaveDialog.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 46%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkImageContainer.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 44%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkMessageBox.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  [ 47%] Building CXX object
CMakeFiles/nomacsCore.dir/src/DkCore/DkMetaData.cpp.o
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  /usr/bin/x86_64-linux-gnu-g++ -DHAVE_EXIV2_HPP -DNDEBUG
-DNOMACS_VERSION=\"3.21\" -DQT_CONCURRENT_LIB -DQT_CORE5COMPAT_LIB
-DQT_CORE_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_NO_DEBUG
-DQT_NO_DEBUG_OUTPUT -DQT_PRINTSUPPORT_LIB -DQT_SVG_LIB
-DQT_WIDGETS_LIB -DWITH_LIBRAW -DWITH_LIBTIFF -DWITH_OPENCV -DW [...]
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.cpp:28:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:610:
CMakeFiles/nomacsCore.dir/src/DkCore/DkImageStorage.cpp.o] Error 1
  make[3]: *** Waiting for unfinished jobs....
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkViewPort.h:30,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkViewPort.cpp:28:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkToolbars.cpp:31:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:470:
CMakeFiles/nomacsCore.dir/src/DkGui/DkViewPort.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:456:
CMakeFiles/nomacsCore.dir/src/DkGui/DkToolbars.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.cpp:28:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkActionManager.cpp:29:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBasicWidgets.cpp:30:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkManipulators.cpp:33:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:498:
CMakeFiles/nomacsCore.dir/src/DkCore/DkActionManager.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:540:
CMakeFiles/nomacsCore.dir/src/DkCore/DkBasicWidgets.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:512:
CMakeFiles/nomacsCore.dir/src/DkCore/DkBaseViewPort.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:624:
CMakeFiles/nomacsCore.dir/src/DkCore/DkManipulators.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkQuickAccess.cpp:30:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:414:
CMakeFiles/nomacsCore.dir/src/DkGui/DkQuickAccess.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkMetaDataWidgets.cpp:31:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:344:
CMakeFiles/nomacsCore.dir/src/DkGui/DkMetaDataWidgets.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkManipulatorsIpl.cpp:31:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:638:
CMakeFiles/nomacsCore.dir/src/DkCore/DkManipulatorsIpl.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkBatch.cpp:33:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:218:
CMakeFiles/nomacsCore.dir/src/DkGui/DkBatch.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkSaveDialog.cpp:29:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:722:
CMakeFiles/nomacsCore.dir/src/DkCore/DkSaveDialog.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu/nomacsCore_autogen/SXXCP4GQFL/../../../ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu/nomacsCore_autogen/SXXCP4GQFL/moc_DkBaseViewPort.cpp:9,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu/nomacsCore_autogen/mocs_compilation.cpp:4:
  /build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu/nomacsCore_autogen/SXXCP4GQFL/../../../ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:190:
CMakeFiles/nomacsCore.dir/nomacsCore_autogen/mocs_compilation.cpp.o]
Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkProcess.cpp:30:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkPreferenceWidgets.cpp:33:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:400:
CMakeFiles/nomacsCore.dir/src/DkGui/DkPreferenceWidgets.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:708:
CMakeFiles/nomacsCore.dir/src/DkCore/DkProcess.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkWidgets.cpp:33:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:484:
CMakeFiles/nomacsCore.dir/src/DkGui/DkWidgets.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkManipulatorWidgets.cpp:32:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBasicLoader.cpp:31:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:316:
CMakeFiles/nomacsCore.dir/src/DkGui/DkManipulatorWidgets.cpp.o] Error
1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:526:
CMakeFiles/nomacsCore.dir/src/DkCore/DkBasicLoader.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkThumbsWidgets.cpp:32:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:442:
CMakeFiles/nomacsCore.dir/src/DkGui/DkThumbsWidgets.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkMetaData.cpp:29:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:680:
CMakeFiles/nomacsCore.dir/src/DkCore/DkMetaData.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkViewPort.h:30,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkCentralWidget.cpp:43:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:232:
CMakeFiles/nomacsCore.dir/src/DkGui/DkCentralWidget.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkViewPort.h:30,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkNoMacs.cpp:54:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:372:
CMakeFiles/nomacsCore.dir/src/DkGui/DkNoMacs.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageLoader.cpp:34:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkDialog.cpp:31:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:596:
CMakeFiles/nomacsCore.dir/src/DkCore/DkImageLoader.cpp.o] Error 1
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:274:
CMakeFiles/nomacsCore.dir/src/DkGui/DkDialog.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkBaseViewPort.h:36,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkViewPort.h:30,
                   from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkGui/DkControlWidget.cpp:39:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:260:
CMakeFiles/nomacsCore.dir/src/DkGui/DkControlWidget.cpp.o] Error 1
  In file included from
/build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageContainer.cpp:30:
  /build/reproducible-path/nomacs-3.21.1+dfsg/ImageLounge/src/DkCore/DkImageStorage.h:41:10:
fatal error: opencv2/imgproc/imgproc_c.h: No such file or directory
     41 | #include "opencv2/imgproc/imgproc_c.h"
        |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  compilation terminated.
  make[3]: *** [CMakeFiles/nomacsCore.dir/build.make:582:
CMakeFiles/nomacsCore.dir/src/DkCore/DkImageContainer.cpp.o] Error 1
  make[3]: Leaving directory
'/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu'
  make[2]: *** [CMakeFiles/Makefile2:159: CMakeFiles/nomacsCore.dir/all] Error 2
  make[2]: Leaving directory
'/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu'
  make[1]: *** [Makefile:159: all] Error 2
  make[1]: Leaving directory
'/build/reproducible-path/nomacs-3.21.1+dfsg/obj-x86_64-linux-gnu'
  dh_auto_build: error: cd obj-x86_64-linux-gnu && make -j40
INSTALL="install --strip-program=true" VERBOSE=1 returned exit code 2
  make: *** [debian/rules:8: binary] Error 25
  dpkg-buildpackage: error: debian/rules binary subprocess failed with
exit status 2

Please close this bug if it turns out to be a collision with another ongoing
transition rather than an OpenCV 5 problem.

Thanks,
Aron