How to add shared library dependencies to debian/control?

I am trying to make a debian package from a Qt application relying on OpenCV. What I did so far: 1. I set up an Ubuntu in a Virtualbox 2. I installed the neccessary software to compile and run the application (Qt related things, ffmpeg, codecs, OpenCV etc.) 3. I successfully compiled and ran the application 4. I created a GPG key 5. With dh_make I created the debian directory in my project dir 6. I added the packages to debian/control->Build Depends what I got by executing dpkg-depcheck -d qmake 7. I added to the Depends also what I got by dpkg-depcheck -d SampleApp 8. I edited the copyright and changelog files 9. I tried to run dpkg-buildpackage -b At this point I got the error message: dpkg-shlibdeps: error: no dependency information found for /usr/local/lib/libopencv_imgcodecs.so.3.1 (used by debian/sampleapp/opt/SampleApp/bin/SampleApp) dh_shlibdeps: dpkg-shlibdeps -Tdebian/sampleapp.substvars debian/sampleapp/opt/SampleApp/bin/SampleApp returned exit code 2 make: *** [binary] Error 2 dpkg-buildpackage: error: debian/rules binary gave error exit status 2 All these files can be found under /usr/local/lib/. I have read this: https://www.debian.org/doc/debian-policy/ch-sharedlibs.html but I could not find the solution. How could I add these dependencies to the package? ### Edit: Build-Depends field: Build-Depends: debhelper (>= 8.0.0), libpopt0:i386, libqt5core5a:i386, qtdeclarative5-dev, libglib2.0-0:i386, qtchooser, pkg-config, qt5-qmake:i386, locales Depends field: Depends: ${shlibs:Depends}, ${misc:Depends}, udev, libxext6:i386, libxcomposite1:i386, libopencore-amrwb0:i386, libglib2.0-0:i386, libpangocairo-1.0-0:i386, libva-drm1:i386, libxinerama1:i386, libmp3lame0:i386, libnih1:i386, libx11-6:i386, libxcb-render0:i386, libffi6:i386, libgdk-pixbuf2.0-0:i386, libdrm2:i386, libvorbis0a:i386, libfontconfig1:i386, libxrender1:i386, libpango-1.0-0:i386, libdbus-1-3:i386, libpixman-1-0:i386, libopenexr6:i386, libxvidcore4:i386, libjpeg-turbo8:i386, libcgmanager0:i386, libcairo2:i386, libjasper1:i386, libxfixes3:i386, libilmbase6:i386, libtiff5:i386, libusb-1.0-0:i386, libdc1394-22:i386, libxi6:i386, libfreetype6:i386, libxrandr2:i386, libqt5network5:i386, libpng12-0:i386, libthai0:i386, libxcb-shm0:i386, libva1:i386, libvorbisenc2:i386, libtheora0:i386, libharfbuzz0b:i386, libicu52:i386, libjbig0:i386, libopencore-amrnb0:i386, libogg0:i386, libxcursor1:i386, libxcb1:i386, libraw1394-11:i386, libudev1:i386, libnih-dbus1:i386, libqt5core5a:i386, libgraphite2-3:i386, libva-x11-1:i386, libatk1.0-0:i386, libexpat1:i386, libgtk2.0-0:i386, libpangoft2-1.0-0:i386, libdatrie1:i386, libxdmcp6:i386, libvdpau1:i386, libxdamage1:i386, libxau6:i386