Installation errors [osx]

[edbond]

go version go1.9.1 darwin/amd64
osx high sierra

Installed opencv first

$ brew install opencv

Next

$ go get github.com/hybridgroup/gocv
# github.com/hybridgroup/gocv
Undefined symbols for architecture x86_64:
  "cv::HoughLines(cv::_InputArray const&, cv::_OutputArray const&, double, double, int, double, double, double, double)", referenced from:
      _HoughLines in imgproc.cpp.o
  "cv::HoughLinesP(cv::_InputArray const&, cv::_OutputArray const&, double, double, int, double, double)", referenced from:
      _HoughLinesP in imgproc.cpp.o
  "cv::VideoWriter::fourcc(char, char, char, char)", referenced from:
      _VideoWriter_Open in videoio.cpp.o
  "cv::VideoWriter::VideoWriter()", referenced from:
      _VideoWriter_New in videoio.cpp.o
  "cv::getTextSize(cv::String const&, int, double, int, int*)", referenced from:
      _GetTextSize in imgproc.cpp.o
  "cv::namedWindow(cv::String const&, int)", referenced from:
      _Window_New in highgui.cpp.o
  "cv::GaussianBlur(cv::_InputArray const&, cv::_OutputArray const&, cv::Size_<int>, double, double, int)", referenced from:
      _GaussianBlur in imgproc.cpp.o
  "cv::VideoCapture::VideoCapture()", referenced from:
      _VideoCapture_New in videoio.cpp.o
  "cv::destroyWindow(cv::String const&)", referenced from:
      _Window_Close in highgui.cpp.o
  "cv::CascadeClassifier::detectMultiScale(cv::_InputArray const&, std::__1::vector<cv::Rect_<int>, std::__1::allocator<cv::Rect_<int> > >&, double, int, int, cv::Size_<int>, cv::Size_<int>)", referenced from:
      _CascadeClassifier_DetectMultiScale in objdetect.cpp.o
  "cv::CascadeClassifier::load(cv::String const&)", referenced from:
      _CascadeClassifier_Load in objdetect.cpp.o
  "cv::CascadeClassifier::CascadeClassifier()", referenced from:
      _CascadeClassifier_New in objdetect.cpp.o
  "cv::CascadeClassifier::~CascadeClassifier()", referenced from:
      _CascadeClassifier_Close in objdetect.cpp.o
  "cv::Mat::deallocate()", referenced from:
      _Mat_Close in core.cpp.o
      _Mat_Clone in core.cpp.o
      _Image_IMRead in imgcodecs.cpp.o
  "cv::Mat::create(int, int const*, int)", referenced from:
      _Mat_NewWithSize in core.cpp.o
  "cv::Mat::copySize(cv::Mat const&)", referenced from:
      _Image_IMRead in imgcodecs.cpp.o
  "cv::Mat::Mat(cv::Mat const&, cv::Rect_<int> const&)", referenced from:
      _Mat_Region in core.cpp.o
  "cv::Mat::operator=(cv::Scalar_<double> const&)", referenced from:
      _Mat_NewWithSize in core.cpp.o
  "cv::blur(cv::_InputArray const&, cv::_OutputArray const&, cv::Size_<int>, cv::Point_<int>, int)", referenced from:
      _Blur in imgproc.cpp.o
  "cv::Canny(cv::_InputArray const&, cv::_OutputArray const&, double, double, int, bool)", referenced from:
      _Canny in imgproc.cpp.o
  "cv::String::deallocate()", referenced from:
      cvflann::anyimpl::big_any_policy<cv::String>::static_delete(void**) in core.cpp.o
      cvflann::anyimpl::big_any_policy<cv::String>::move(void* const*, void**) in core.cpp.o
      _Window_New in highgui.cpp.o
      _Window_Close in highgui.cpp.o
      _Window_IMShow in highgui.cpp.o
      cvflann::anyimpl::big_any_policy<cv::String>::static_delete(void**) in highgui.cpp.o
      cvflann::anyimpl::big_any_policy<cv::String>::move(void* const*, void**) in highgui.cpp.o
      ...
  "cv::String::allocate(unsigned long)", referenced from:
      _Window_New in highgui.cpp.o
      _Window_Close in highgui.cpp.o
      _Window_IMShow in highgui.cpp.o
      _Image_IMRead in imgcodecs.cpp.o
      _Image_IMWrite in imgcodecs.cpp.o
      _Image_IMEncode in imgcodecs.cpp.o
      _GetTextSize in imgproc.cpp.o
      ...
  "cv::imread(cv::String const&, int)", referenced from:
      _Image_IMRead in imgcodecs.cpp.o
  "cv::imshow(cv::String const&, cv::_InputArray const&)", referenced from:
      _Window_IMShow in highgui.cpp.o
  "cv::imwrite(cv::String const&, cv::_InputArray const&, std::__1::vector<int, std::__1::allocator<int> > const&)", referenced from:
      _Image_IMWrite in imgcodecs.cpp.o
  "cv::putText(cv::_InputOutputArray const&, cv::String const&, cv::Point_<int>, int, double, cv::Scalar_<double>, int, int, bool)", referenced from:
      _PutText in imgproc.cpp.o
  "cv::waitKey(int)", referenced from:
      _Window_WaitKey in highgui.cpp.o
  "cv::cvtColor(cv::_InputArray const&, cv::_OutputArray const&, int, int)", referenced from:
      _CvtColor in imgproc.cpp.o
  "cv::fastFree(void*)", referenced from:
      _Mat_Close in core.cpp.o
      _Mat_Clone in core.cpp.o
      _Image_IMRead in imgcodecs.cpp.o
  "cv::imencode(cv::String const&, cv::_InputArray const&, std::__1::vector<unsigned char, std::__1::allocator<unsigned char> >&, std::__1::vector<int, std::__1::allocator<int> > const&)", referenced from:
      _Image_IMEncode in imgcodecs.cpp.o
  "cv::rectangle(cv::_InputOutputArray const&, cv::Point_<int>, cv::Point_<int>, cv::Scalar_<double> const&, int, int, int)", referenced from:
      _Rectangle in imgproc.cpp.o
  "cv::Mat::copyTo(cv::_OutputArray const&) const", referenced from:
      _Mat_Clone in core.cpp.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

[ariesdevil]

Same error on MacOS High Sierra.

[edbond]

$ brew info opencv                           
opencv: stable 3.3.0 (bottled)
Open source computer vision library
http://opencv.org/
/usr/local/Cellar/opencv/3.3.0_3 (516 files, 123MB) *
  Poured from bottle on 2017-10-11 at 10:17:19
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/opencv.rb
==> Dependencies
Build: cmake ✘, pkg-config ✔
Required: eigen ✔, ffmpeg ✔, jpeg ✔, libpng ✔, libtiff ✔, openexr ✔, numpy ✔
==> Requirements
Required: python ✔, python3 ✔

[deadprogram]

Hello, everyone.

Can you please try:

go get -d -u github.com/hybridgroup/gocv

The problem might be that go is trying to install before the pre-reqs are installed, or before the ENV vars are set as needed for your platform.

[edbond]

-d will not install

The -d flag instructs get to stop after downloading the packages; that is,
it instructs get not to install the packages.

Ran -d -u and then
$ go get -u github.com/hybridgroup/gocv results in the same error.

[edbond]

The build debug go build -v -x last command:

.......
cd /Users/eduard/go/default/src/gocv
clang++ -I . -fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=$WORK=/tmp/go-build -gno-record-gcc-switches -fno-common -o $WORK/gocv/_obj/_cgo_.o $WORK/gocv/_obj/_cgo_main.o $WORK/gocv/_obj/_cgo_export.o $WORK/gocv/_obj/core.cgo2.o $WORK/gocv/_obj/highgui.cgo2.o $WORK/gocv/_obj/imgcodecs.cgo2.o $WORK/gocv/_obj/imgproc.cgo2.o $WORK/gocv/_obj/objdetect.cgo2.o $WORK/gocv/_obj/version.cgo2.o $WORK/gocv/_obj/videoio.cgo2.o $WORK/gocv/_obj/core.cpp.o $WORK/gocv/_obj/highgui.cpp.o $WORK/gocv/_obj/imgcodecs.cpp.o $WORK/gocv/_obj/imgproc.cpp.o $WORK/gocv/_obj/objdetect.cpp.o $WORK/gocv/_obj/version.cpp.o $WORK/gocv/_obj/videoio.cpp.o -g -O2
# gocv
Undefined symbols for architecture x86_64:
  "cv::HoughLines(cv::_InputArray const&, cv::_OutputArray const&, double, double, int, double, double, double, double)", referenced from:
      _HoughLines in imgproc.cpp.o
  "cv::HoughLinesP(cv::_InputArray const&, cv::_OutputArray const&, double, double, int, double, double)", referenced from:
.......

I think there should be cgo comment to include opencv lib in LDFLAGS like

// #cgo LDFLAGS: -lpng

I am not familiar with opencv, will let you know if find a way to fix.

[deadprogram]

I think you need to first need to download:

go get -d -u github.com/hybridgroup/gocv

Once the package is downloaded, you would need to run the env.sh script to setup the build vars:

cd $GOPATH/src/github.com/hybridgroup/gocv
source ./env.sh

Once the env vars are set in that session, you should be able to try running code, such as the version command:

go run ./cmd/version/main.go

Please give that a try.

[edbond]

Yes, that works. Thanks.

$ source ./env.sh                
Environment variables configured for OSX
$ go run ./cmd/version/main.go 
gocv version: 0.1.0
opencv lib version: 3.3.0

[deadprogram]

This is mentioned already here https://github.com/hybridgroup/gocv#how-to-buildrun-code but will need the go get -d -u part added.

[deadprogram]

The README has been updated here ae24310 and the website here hybridgroup/gocv-site@898b709

I will close this issue once it is pushed to master. Thanks @edbond & @ariesdevil for your bug reports and assistance.

[deadprogram]

OK this has now been released. Now closing, thank you again everyone.

[llitfkitfk]

[deadprogram]

Hi @llitfkitfk from your log, looks like you are trying to build for iOS simulator, not Mac OS. Check your XCode default settings.