osx 10.9 opencv build error

[mrnugget]

osx 10.9 opencv build error

[mrnugget]

That's weird. It worked for me just a couple of weeks ago on OS X.

Yeah, g++ can't find OpenCV in your output. Did you check what the pkg-config line returns? Do you have opencv installed? In a standard location or somewhere else?

[brannondorsey]

Hi there, I've been helping @kaylalewis install and use this awesome package. We cloned and successfully built the version of openCV you mentioned in the README. Once we downloaded openCV to ~/ we moved into the root openCV directory and ran:

cmake # which successfully generated build files
make -j8
make install

Which built and installed openCV binaries. Would this have also built and installed the necessary lib files (like opencv2) and installed them to $PATH?

[mrnugget]

As far as I know, lib files don't get moved into $PATH, only executables should. And I don't know what the make install step of OpenCV does exactly.

What needs to happen is g++ getting the correct -I and -l flags passed to it. It also needs the correct dylib files (on OS X) to compile. In the instructions I use pkg-config for that. The output of pkg-config looks like this on my machine:

$ pkg-config --libs --cflags opencv | sed 's/libtbb\.dylib/tbb/'
-I/usr/local/Cellar/opencv/2.4.9/include/opencv -I/usr/local/Cellar/opencv/2.4.9/include /usr/local/Cellar/opencv/2.4.9/lib/libopencv_calib3d.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_contrib.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_core.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_features2d.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_flann.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_gpu.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_highgui.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_imgproc.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_legacy.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_ml.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_nonfree.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_objdetect.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_ocl.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_photo.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_stitching.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_superres.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_ts.a /usr/local/Cellar/opencv/2.4.9/lib/libopencv_video.dylib /usr/local/Cellar/opencv/2.4.9/lib/libopencv_videostab.dylib -ltbb

So if you can reproduce this with your manual OpenCV installation it should work.

[brannondorsey]

I am now trying to build on my OSX 10.10 machine (following the same steps in the README) and I am also receiving errors on step 6. pkg-config --libs --cflags opencv | sed 's/libtbb\.dylib/tbb/' output is:

-I/usr/local/Cellar/opencv/2.4.9/include/opencv 
-I/usr/local/Cellar/opencv/2.4.9/include 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_calib3d.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_contrib.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_core.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_features2d.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_flann.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_gpu.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_highgui.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_imgproc.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_legacy.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_ml.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_nonfree.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_objdetect.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_ocl.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_photo.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_stitching.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_superres.dylib
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_ts.a 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_video.dylib 
/usr/local/Cellar/opencv/2.4.9/lib/libopencv_videostab.dylib 

which, to spare you the comparison, is exactly the output of yours excluding the -ltbb flag which errors with library not found. The main error is that -lopencv_core isn't found, which is strange because I have the dylib installed in a place where pkg-config can find it. Any thoughts?

[mrnugget]

I actually have no idea. You're basically running the same setup as I do.

But it's not pkg-config that needs to find the library, it's g++ that needs access. pkg-config only provides us with the flags to pass to g++ so it can find the libraries.

Just a quick guess: is your g++ command correctly constructed?

[mrnugget]

I'm closing this for now.

[bogong17]

Hey guys, I got the same error..
Did you fix it?
Thank you so much///

[arturgrigor]

I had lots of issues with building the mergevec tool on OS X Yosemite but I've managed to fix them like this:

g++ `pkg-config --libs --cflags opencv` -I. -I/usr/local/Cellar/opencv/2.4.12_2/include/opencv -I/usr/local/Cellar/opencv/2.4.12_2/include -o mergevec mergevec.cpp\
  cvboost.cpp cvcommon.cpp cvsamples.cpp cvhaarclassifier.cpp\
  cvhaartraining.cpp cvsamplesoutput.cpp\
  -L/usr/local/Cellar/opencv/2.4.12_2/lib\
  -lopencv_core -lopencv_calib3d -lopencv_imgproc -lopencv_highgui -lopencv_objdetect

Notes

• The opencv package has been installed using Homebrew and the installed version was 2.4.12
• You need to run export DYLD_LIBRARY_PATH=/usr/local/lib in case you run into this error ld: library not found for -llibtbb.dylib
• -I/usr/local/Cellar/opencv/2.4.12_2/include/opencv -I/usr/local/Cellar/opencv/2.4.12_2/include is needed in case of this error mergevec.cpp:1:10: fatal error: 'cv.h' file not found
• You also need to include the cvsamplesoutput.cpp in case you run into this problem JpgDatasetGenerator::JpgDatasetGenerator(char const*) in cvhaartraining-8f5a1b.o