OpenCV / Android Compilation Errors

Question

I am currently following this guide (http://www.stanford.edu/class/ee368/Android/Tutorial-2-OpenCV-for-Android-Setup-Windows.pdf) on how to configure OpenCV for Android on Windows , and I have some errors that I don’t understand. Basically, in step 3.c, when I compile the OpenCV libraries in Cygwin using the make command, I get these errors;

/home/Ralph/opencv/modules/legacy/src/calibfilter.cpp: In member function `virtual bool CvCalibFilter::SaveCameraParams(const char*)': /home/Ralph/opencv/modules/legacy/src/calibfilter.cpp:693: error: `struct CvStereoCamera' has no member named `quad' /home/Ralph/opencv/modules/legacy/src/calibfilter.cpp:694: error: `struct CvStereoCamera' has no member named `quad' /home/Ralph/opencv/modules/legacy/src/calibfilter.cpp: In member function `virtual bool CvCalibFilter::LoadCameraParams(const char*)': /home/Ralph/opencv/modules/legacy/src/calibfilter.cpp:749: error: `struct CvStereoCamera' has no member named `quad' /home/Ralph/opencv/modules/legacy/src/calibfilter.cpp:750: error: `struct CvStereoCamera' has no member named `quad' make[2]: *** [modules/legacy/CMakeFiles/opencv_legacy.dir/src/calibfilter.o] Error 1 make[1]: *** [modules/legacy/CMakeFiles/opencv_legacy.dir/all] Error 2 make: *** [all] Error 2 

Thanks for your help in advance,

Ralph.

Answer 1

At the top of both calibfilter.cpp and epilines.cpp is "#undef quad". If I comment on these undefs, it compiles successfully.

In my life, I cannot understand why there is undef ... maybe the import order is wrong or something like that.

Answer 2

I ran into the same problem. Considering /home/Ralph/opencv/modules/legacy/include/opencv2/legacy/legacy.hpp , the structure definition:

 typedef struct CvStereoCamera { CvCamera* camera[2]; /* two individual camera parameters */ float fundMatr[9]; /* fundamental matrix */ /* New part for stereo */ CvPoint3D32f epipole[2]; CvPoint2D32f quad[2][4]; /* coordinates of destination quadrangle after epipolar geometry rectification */ double coeffs[2][3][3];/* coefficients for transformation */ CvPoint2D32f border[2][4]; CvSize warpSize; CvStereoLineCoeff* lineCoeffs; int needSwapCameras;/* flag set to 1 if need to swap cameras for good reconstruction */ float rotMatrix[9]; float transVector[3]; } CvStereoCamera; 

I am completely puzzled by why it doesn't seem to work: quad is defined right there.

calibfilter.cpp commented on all the lines in calibfilter.cpp and epilines.cpp that refer to the quad attribute, I managed to get at least an OpenCV compilation, but this, without a doubt, broke the stereo sound support.

Answer 3

Installing OpenCV on Windows is easy.

Follow these steps.

http://www.developerstation.org/2011/02/using-opencv-21-on-visual-studio-2008.html

The link you mentioned does not use the official NDK supported by Google. I had problems setting up and working with ndk4 in the past.

If you work or work with ndk4, it doesn’t matter to you that official links (with NDK 5) work fine. Give it a try. These are basically the same steps.

http://opencv.itseez.com/doc/tutorials/introduction/android_binary_package/android_binary_package.html

http://opencv.itseez.com/doc/tutorials/introduction/android_binary_package/android_binary_package_using_with_NDK.html

Answer 4

As @Matthew Hemke wrote, #undef is the culprit. What strange bccoz code compiles fine, like in Ubuntu, but when I encountered a similar "No member Quad" error compiling OpenCV under Cygwin (on windows-7). There is nothing significant here.