The obvious question is do you have OpenCV installed on CentOS? It seems not... In fact, I would assume that you would get a link error if you tried building on CentOS. CentOS is a Fedora derivitive. The Red Hat developers don't like software is isn't completely open source. OpenCV is released under the BSD license, so it may not be easily provided to CentOS (via rpm). You may have to download the source and build it yourself. If so, you need to be mindful of glib version compatibility. You might also be able to get it from rpm forge, which you should check first. <div class="gmail_quote">On Mon, Jul 30, 2012 at 11:02 AM, iron_guitarist1987 <<a href="mailto:jtrinidadperez@gmail.com" target="_blank">jtrinidadperez@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hello all, I have a plugin that uses OpenCV and it works perfectly on Kubuntu. Now I am trying to run the code on CentOS but when I run the pipeline, I get: $ gst-launch videotestsrc ! opencvelement ! ximagesink WARNING: erroneous pipeline: no element "opencvelement" When I run ldd in Kubuntu, I get: $ ldd .libs/libOPENCVELEMENT.so linux-gate.so.1 => (0x0060f000) libgstbase-0.10.so.0 => /usr/lib/libgstbase-0.10.so.0 (0x00a74000) libgstreamer-0.10.so.0 => /usr/lib/libgstreamer-0.10.so.0 (0x00474000) libgobject-2.0.so.0 => /usr/lib/i386-linux-gnu/libgobject-2.0.so.0 (0x006a2000) libglib-2.0.so.0 => /lib/i386-linux-gnu/libglib-2.0.so.0 (0x00110000) libopencv_core.so.2.3 => /usr/local/lib/libopencv_core.so.2.3 (0x00730000) libstdc++.so.6 => /usr/lib/i386-linux-gnu/libstdc++.so.6 (0x00209000) libm.so.6 => /lib/i386-linux-gnu/libm.so.6 (0x002f4000) libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0x00acd000) libgcc_s.so.1 => /lib/i386-linux-gnu/libgcc_s.so.1 (0x0031e000) libpthread.so.0 => /lib/i386-linux-gnu/libpthread.so.0 (0x0033c000) libgthread-2.0.so.0 => /usr/lib/i386-linux-gnu/libgthread-2.0.so.0 (0x00357000) libgmodule-2.0.so.0 => /usr/lib/i386-linux-gnu/libgmodule-2.0.so.0 (0x0035d000) libxml2.so.2 => /usr/lib/libxml2.so.2 (0x00c9c000) librt.so.1 => /lib/i386-linux-gnu/librt.so.1 (0x00362000) libdl.so.2 => /lib/i386-linux-gnu/libdl.so.2 (0x0036b000) libffi.so.6 => /usr/lib/i386-linux-gnu/libffi.so.6 (0x00370000) libpcre.so.3 => /lib/i386-linux-gnu/libpcre.so.3 (0x00e52000) libz.so.1 => /lib/i386-linux-gnu/libz.so.1 (0x00377000) /lib/ld-linux.so.2 (0x00a10000) But when I run it on CentOS, I don't see opencv $ ldd .libs/libOPENCVELEMENT.so linux-vdso.so.1 => (0x00007fff7a1fd000) libgstvideo-0.10.so.0 => /usr/lib64/libgstvideo-0.10.so.0 (0x00002ba0ac9b7000) libgstcontroller-0.10.so.0 => /usr/lib64/libgstcontroller-0.10.so.0 (0x00002ba0acbc4000) libgstbase-0.10.so.0 => /usr/lib64/libgstbase-0.10.so.0 (0x00002ba0acdeb000) libgstreamer-0.10.so.0 => /usr/lib64/libgstreamer-0.10.so.0 (0x00002ba0ad03c000) libgobject-2.0.so.0 => /lib64/libgobject-2.0.so.0 (0x00002ba0ad326000) libgmodule-2.0.so.0 => /lib64/libgmodule-2.0.so.0 (0x00002ba0ad569000) libgthread-2.0.so.0 => /lib64/libgthread-2.0.so.0 (0x00002ba0ad76c000) librt.so.1 => /lib64/librt.so.1 (0x00002ba0ad970000) libxml2.so.2 => /usr/lib64/libxml2.so.2 (0x00002ba0adb7a000) libz.so.1 => /lib64/libz.so.1 (0x00002ba0adeb7000) libglib-2.0.so.0 => /lib64/libglib-2.0.so.0 (0x00002ba0ae0cb000) libstdc++.so.6 => /usr/lib64/libstdc++.so.6 (0x00002ba0ae3a8000) libm.so.6 => /lib64/libm.so.6 (0x00002ba0ae6a8000) libc.so.6 => /lib64/libc.so.6 (0x00002ba0ae92b000) libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x00002ba0aec83000) libpthread.so.0 => /lib64/libpthread.so.0 (0x00002ba0aee91000) libdl.so.2 => /lib64/libdl.so.2 (0x00002ba0af0ac000) /lib64/ld-linux-x86-64.so.2 (0x0000003f6c800000) Here is my <a href="http://makefile.am" target="_blank">makefile.am</a>, which is the same on both OS plugin_LTLIBRARIES = libOPENCVELEMENT.la # Plugin source files: libOPENCVELEMENT_la_SOURCES = opencv_chain.c opencv_chain.h datasetup.h libOPENCVELEMENT_la_CFLAGS = \ $(GST_PLUGINS_BASE_CFLAGS) \ $(GST_CFLAGS) \ $(OPENCV_CFLAGS) libOPENCVELEMENT_la_CXXFLAGS = \ $(GST_PLUGINS_BASE_CFLAGS) \ $(GST_CFLAGS) \ $(OPENCV_CFLAGS) libOPENCVELEMENT_la_LIBADD = \ $(GST_PLUGINS_BASE_LIBS) \ $(GST_LIBS) \ $(OPENCV_LIBS) \ -lopencv_core \ -lopencv_highgui libOPENCVELEMENT_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS) libOPENCVELEMENT_la_LIBTOOLFLAGS = --tag=disable-static Let me know if you need more information. Any help will be appreciated. Thank you. ----- The greatest trick the devil ever pulled was convincing the World that Java was better than C++. -- View this message in context: <a href="http://gstreamer-devel.966125.n4.nabble.com/gstreamer-plugin-library-not-linking-against-opencv-shared-object-library-undefined-symbol-on-Kubuntu-tp4655749.html" target="_blank">http://gstreamer-devel.966125.n4.nabble.com/gstreamer-plugin-library-not-linking-against-opencv-shared-object-library-undefined-symbol-on-Kubuntu-tp4655749.html</a> Sent from the GStreamer-devel mailing list archive at Nabble.com. _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div>