关于OpenCV3.0 beta 编译出现ORB那边的错误的解决

好久没碰opencv了，现在已经3.0 beta了。

今天编译遇到了error: cannot declare variable ‘orb’ to be of abstract type ‘cv::ORB

原因是ORB这个类不能再这么调用了。

在opencv 根目录找到opencvroot/samples/gpu/performance/tests.cpp

修改成如下代码。

TEST(ORB)
{
    Mat src = imread(abspath("../data/aloeL.jpg"), IMREAD_GRAYSCALE);
    if (src.empty()) throw runtime_error("can't open ../data/aloeL.jpg");

//ORB orb(4000);
    Ptr<ORB> orb = ORB::create(4000,1.2f,8,31,0,2,ORB::HARRIS_SCORE,31,20);
    vector<KeyPoint> keypoints;
    Mat descriptors;
   
    orb->detectAndCompute(src, Mat(), keypoints, descriptors);

//orb(src, Mat(), keypoints, descriptors);

CPU_ON;
    //orb(src, Mat(), keypoints, descriptors);
    orb->detectAndCompute(src, Mat(), keypoints, descriptors);
    CPU_OFF;

cuda::ORB_CUDA d_orb;
    cuda::GpuMat d_src(src);
    cuda::GpuMat d_keypoints;
    cuda::GpuMat d_descriptors;

d_orb(d_src, cuda::GpuMat(), d_keypoints, d_descriptors);

CUDA_ON;
    d_orb(d_src, cuda::GpuMat(), d_keypoints, d_descriptors);
    CUDA_OFF;
}

这里说明原因，我查看了opencv3.0的feature2d.hpp代码发现

class CV_EXPORTS_W ORB : public Feature2D 
{ 
public: 
    enum { kBytes = 32, HARRIS_SCORE=0, FAST_SCORE=1 }; 
 
    CV_WRAP static Ptr<ORB> create(int nfeatures=500, float scaleFactor=1.2f, int nlevels=8, int edgeThreshold=31, 
        int firstLevel=0, int WTA_K=2, int scoreType=ORB::HARRIS_SCORE, int patchSize=31, int fastThreshold=20);
 
    CV_WRAP virtual void setMaxFeatures(int maxFeatures) = 0; 
    CV_WRAP virtual int getMaxFeatures() const = 0; 
 
    CV_WRAP virtual void setScaleFactor(double scaleFactor) = 0; 
    CV_WRAP virtual double getScaleFactor() const = 0; 
 
    CV_WRAP virtual void setNLevels(int nlevels) = 0; 
    CV_WRAP virtual int getNLevels() const = 0; 
 
    CV_WRAP virtual void setEdgeThreshold(int edgeThreshold) = 0; 
    CV_WRAP virtual int getEdgeThreshold() const = 0; 
 
    CV_WRAP virtual void setFirstLevel(int firstLevel) = 0; 
    CV_WRAP virtual int getFirstLevel() const = 0; 
 
    CV_WRAP virtual void setWTA_K(int wta_k) = 0; 
    CV_WRAP virtual int getWTA_K() const = 0; 
 
    CV_WRAP virtual void setScoreType(int scoreType) = 0; 
    CV_WRAP virtual int getScoreType() const = 0; 
 
    CV_WRAP virtual void setPatchSize(int patchSize) = 0; 
    CV_WRAP virtual int getPatchSize() const = 0; 
 
    CV_WRAP virtual void setFastThreshold(int fastThreshold) = 0; 
    CV_WRAP virtual int getFastThreshold() const = 0; 
}; 

没有构造函数，只有一个静态的create。

此外，检测函数也不能用原来的操作符重载的检测函数了。

class ORB_Impl : public ORB 
{ 
public: 
    explicit ORB_Impl(int _nfeatures, float _scaleFactor, int _nlevels, int _edgeThreshold, 
            int _firstLevel, int _WTA_K, int _scoreType, int _patchSize, int _fastThreshold) : 
        nfeatures(_nfeatures), scaleFactor(_scaleFactor), nlevels(_nlevels), 
        edgeThreshold(_edgeThreshold), firstLevel(_firstLevel), wta_k(_WTA_K), 
        scoreType(_scoreType), patchSize(_patchSize), fastThreshold(_fastThreshold) 
    {} 
 
    void setMaxFeatures(int maxFeatures) { nfeatures = maxFeatures; } 
    int getMaxFeatures() const { return nfeatures; } 
 
    void setScaleFactor(double scaleFactor_) { scaleFactor = scaleFactor_; } 
    double getScaleFactor() const { return scaleFactor; } 
 
    void setNLevels(int nlevels_) { nlevels = nlevels_; } 
    int getNLevels() const { return nlevels; } 
 
    void setEdgeThreshold(int edgeThreshold_) { edgeThreshold = edgeThreshold_; } 
    int getEdgeThreshold() const { return edgeThreshold; } 
 
    void setFirstLevel(int firstLevel_) { firstLevel = firstLevel_; } 
    int getFirstLevel() const { return firstLevel; } 
 
    void setWTA_K(int wta_k_) { wta_k = wta_k_; } 
    int getWTA_K() const { return wta_k; } 
 
    void setScoreType(int scoreType_) { scoreType = scoreType_; } 
    int getScoreType() const { return scoreType; } 
 
    void setPatchSize(int patchSize_) { patchSize = patchSize_; } 
    int getPatchSize() const { return patchSize; } 
 
    void setFastThreshold(int fastThreshold_) { fastThreshold = fastThreshold_; } 
    int getFastThreshold() const { return fastThreshold; } 
 
    // returns the descriptor size in bytes 
    int descriptorSize() const; 
    // returns the descriptor type 
    int descriptorType() const; 
    // returns the default norm type 
    int defaultNorm() const; 
 
    // Compute the ORB_Impl features and descriptors on an image 
    <strong>void detectAndCompute( InputArray image, InputArray mask, std::vector<KeyPoint>& keypoints, 
                    OutputArray descriptors, bool useProvidedKeypoints=false );</strong> 
 
protected: 
 
    int nfeatures; 
    double scaleFactor; 
    int nlevels; 
    int edgeThreshold; 
    int firstLevel; 
    int wta_k; 
    int scoreType; 
    int patchSize; 
    int fastThreshold; 
};   

希望有人遇到这样的问题的时候，能够得到解答。

此外还有就是使用最新的cuda6.5的时候一定要在gui的cmake 中

将CUDA_ARCH_BIN 设置为2.0 2.1(2.0) 3.0 3.5

不要带1.1 .1.2 1.3等等之类的，因为cuda6.5不支持这些老显卡了。

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