Another OpenCV / cvBlob and Architecture Issue
===

Although this has been asked before, by a number of people, this is not the basic install question (while the answer may be simple).

OK, I am running two install of OpenCV side-by-side (2.3.1 and the latest 2.4) but I primarily use 2.3.1.

So, I have had cvBlob working fine before (on the same machine) but I came around to doing some reinstall. Anywho, I have build OpenCV successfully and I have made the change from the CvBlob project site to include the [OpenCV library in the CMakeLists.txt][1]

To make sure that OpenCV was fine, I have run and re-run make and make install to ensure it is in the usr/local/include directory. Test applications using OpenCV work fine and using`file opencv_library.dylib` shows that the opencv libs are 64 bit.

On to the crux of the problem, I run `cmake .` from the root of the cvblob dir and all comes back fine. `make` and then `sudo make install` is run and I am told that all went well. Again, `file` shows that libcvblob is a 64 bit library, although I am not using it.

I go to a c++ program that uses both opencv and cvblob, with absolute paths to opencv.hpp and cvblob.h as includes.

Then, this:

`Undefined symbols for architecture x86_64:
  "_cvLabel", referenced from:
      _main in cchIl24a.o
  "_cvFilterByArea", referenced from:
      _main in cchIl24a.o
ld: symbol(s) not found for architecture x86_64
collect2: ld returned 1 exit status`

Not sure what has gone wrong, aside from the obvious, but it should have linked to the opencv libs and I cannot see where I may have gone wrong. Has anybody got any ideas?

  [1]: http://code.google.com/p/cvblob/wiki/HowToInstall