install opencv for perl (centos) - perl

Question

I'm trying to do face detection on perl, and I found out about OpenCV and the perl module Image::ObjectDetect on CPAN here and here. I've done a clean install of CentOS 6.5 (minimal) on a virtual machine to test this, and then:
yum -y update
yum -y install perl cpan opencv
Ok, and considering I never user cpan before, I tried the obvious (after some short google searches)
perl -MCPAN -e shell
[accept default]
install Image::ObjectDetect
that gave me some errors:
Package opencv was not found in the pkg-config search path.
Perhaps you should add the directory containing `opencv.pc'
to the PKG_CONFIG_PATH environment variable
No package 'opencv' found
After googling about that error, I did:
export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
mkdir /usr/local/lib/pkgconfig
vi /usr/local/lib/pkgconfig/opencv.pc
the content of the file:
prefix=/usr
exec_prefix=${prefix}
includedir=${prefix}/include
libdir=${exec_prefix}/lib
Name: opencv
Description: The opencv library
Version: 2.x.x
Cflags: -I${includedir}/opencv -I${includedir}/opencv2
Libs: -L${libdir} -lopencv_calib3d -lopencv_imgproc -lopencv_contrib -lopencv_legacy -l
After I ran the install again, I noticed I was missing gcc:
/bin/sh: gcc: command not found
yum -y install gcc
Running the install again now gives me:
...
Note (probably harmless): No library found for -lopencv_calib3d
Note (probably harmless): No library found for -lopencv_imgproc
Note (probably harmless): No library found for -lopencv_contrib
Note (probably harmless): No library found for -lopencv_legacy
Note (probably harmless): No library found for -l
Writing Makefile for Image::ObjectDetect
Could not read '/root/.cpan/build/Image-ObjectDetect-0.12-BsNNjF/META.yml'. Falling back to other methods to determine prerequisites
cp lib/Image/ObjectDetect.pm blib/lib/Image/ObjectDetect.pm
cp lib/Image/ObjectDetect.xs blib/lib/Image/ObjectDetect.xs
/usr/bin/perl /usr/share/perl5/ExtUtils/xsubpp -typemap /usr/share/perl5/ExtUtils/typemap ObjectDetect.xs > ObjectDetect.xsc && mv ObjectDetect.xsc ObjectDetect.c
gcc -c -I/usr/include/opencv -I/usr/include/opencv2 -Isrc -I/usr/include/opencv -I/usr/include/opencv2 -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i686 -mtune=atom -fasynchronous-unwind-tables -DVERSION=\"0.12\" -DXS_VERSION=\"0.12\" -fPIC "-I/usr/lib/perl5/CORE" ObjectDetect.c
In file included from ObjectDetect.xs:7:
/usr/lib/perl5/CORE/cv.h:13: error: redefinition of ‘struct xpvcv’
/usr/lib/perl5/CORE/cv.h:94: error: conflicting types for ‘xpvcv_allocated’
/usr/lib/perl5/CORE/cv.h:94: note: previous declaration of ‘xpvcv_allocated’ was here
ObjectDetect.xs:8:21: error: highgui.h: No such file or directory
ObjectDetect.xs: In function ‘XS_Image__ObjectDetect_new’:
ObjectDetect.xs:19: error: ‘CvHaarClassifierCascade’ undeclared (first use in this function)
ObjectDetect.xs:19: error: (Each undeclared identifier is reported only once
ObjectDetect.xs:19: error: for each function it appears in.)
ObjectDetect.xs:19: error: ‘cascade’ undeclared (first use in this function)
ObjectDetect.xs:22: warning: implicit declaration of function ‘cvLoad’
ObjectDetect.xs: In function ‘XS_Image__ObjectDetect_xs_detect’:
ObjectDetect.xs:37: error: ‘IplImage’ undeclared (first use in this function)
ObjectDetect.xs:37: error: ‘img’ undeclared (first use in this function)
ObjectDetect.xs:37: error: ‘gray’ undeclared (first use in this function)
ObjectDetect.xs:37: warning: left-hand operand of comma expression has no effect
ObjectDetect.xs:39: error: ‘CvMemStorage’ undeclared (first use in this function)
ObjectDetect.xs:39: error: ‘storage’ undeclared (first use in this function)
ObjectDetect.xs:40: error: ‘CvHaarClassifierCascade’ undeclared (first use in this function)
ObjectDetect.xs:40: error: ‘cascade’ undeclared (first use in this function)
ObjectDetect.xs:41: error: ‘CvSeq’ undeclared (first use in this function)
ObjectDetect.xs:41: error: ‘objects’ undeclared (first use in this function)
ObjectDetect.xs:42: error: ‘CvRect’ undeclared (first use in this function)
ObjectDetect.xs:42: error: ‘rect’ undeclared (first use in this function)
ObjectDetect.xs:46: warning: implicit declaration of function ‘cvLoadImage’
ObjectDetect.xs:50: warning: implicit declaration of function ‘cvCreateImage’
ObjectDetect.xs:50: warning: implicit declaration of function ‘cvSize’
ObjectDetect.xs:51: warning: implicit declaration of function ‘cvCvtColor’
ObjectDetect.xs:51: error: ‘CV_BGR2GRAY’ undeclared (first use in this function)
ObjectDetect.xs:52: warning: implicit declaration of function ‘cvEqualizeHist’
ObjectDetect.xs:54: warning: implicit declaration of function ‘cvCreateMemStorage’
ObjectDetect.xs:55: error: expected expression before ‘)’ token
ObjectDetect.xs:56: warning: implicit declaration of function ‘cvHaarDetectObjects’
ObjectDetect.xs:58: error: ‘CV_HAAR_DO_CANNY_PRUNING’ undeclared (first use in this function)
ObjectDetect.xs:65: error: expected expression before ‘)’ token
ObjectDetect.xs:74: warning: implicit declaration of function ‘cvReleaseMemStorage’
ObjectDetect.xs:75: warning: implicit declaration of function ‘cvReleaseImage’
ObjectDetect.xs: In function ‘XS_Image__ObjectDetect_DESTROY’:
ObjectDetect.xs:86: error: ‘CvHaarClassifierCascade’ undeclared (first use in this function)
ObjectDetect.xs:86: error: ‘cascade’ undeclared (first use in this function)
ObjectDetect.xs:88: error: expected expression before ‘)’ token
ObjectDetect.xs:89: warning: implicit declaration of function ‘cvReleaseHaarClassifierCascade’
make: *** [ObjectDetect.o] Error 1
JIRO/Image-ObjectDetect-0.12.tar.gz
/usr/bin/make -- NOT OK
Warning (usually harmless): 'YAML' not installed, will not store persistent state
Running make test
Can't test without successful make
Running make install
Make had returned bad status, install seems impossible
Failed during this command:
JIRO/Image-ObjectDetect-0.12.tar.gz : make NO
Any help? Thanks.

Answer 1

Glad to see someone using OpenCV with Perl! I hope you can get it working and show us some nice asps and scripts :-)
You seem to be building from source and installing packages (with yum) - this sometimes complicates matters when it comes to dependencies. For example, you may have a version of OpenCV that is too new for the CPAN module. Image::ObjectDetect` is fairly old
(the last release was several years ago http://metacpan.org/pod/Image::ObjectDetect) whereas OpenCV is being actively developed.
Note this line:
ObjectDetect.xs:8:21: error: highgui.h: No such file or directory
I came across a similar error compiling applications that depend on OpenCV after a recent update. Either the header files were missing; the applications Makefiles did not know how to locate them; or other development libraries and headers in the chain of dependencies needed updating as well.
You may get better luck solving this by posting to the OpenCV development list where the error message may look more familiar.
See: http://groups.yahoo.com/neo/groups/OpenCV/info
You could try installing some other modules to see if it is perl, XS, gcc or your version of OpenCV that is at fault. Here's another module that uses OpenCV:
https://github.com/shisful/Image-OpenCV