PCA_.cpp

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#include "mexopencv.hpp"
using namespace std;
using namespace cv;

namespace {
// Persistent objects
int last_id = 0;
map<int,Ptr<PCA> > obj_;

const ConstMap<std::string,int> DataAs = ConstMap<std::string,int>
    ("Row", PCA::DATA_AS_ROW)
    ("Col", PCA::DATA_AS_COL);
}

void mexFunction(int nlhs, mxArray *plhs[], int nrhs, const mxArray *prhs[])
{
    // Check the number of arguments
    nargchk(nrhs>=2 && nlhs<=1);

    // Argument vector
    vector<MxArray> rhs(prhs, prhs+nrhs);
    int id = rhs[0].toInt();
    string method(rhs[1].toString());

    // Constructor call
    if (method == "new") {
        nargchk(nrhs==2 && nlhs<=1);
        obj_[++last_id] = makePtr<PCA>();
        plhs[0] = MxArray(last_id);
        mexLock();
        return;
    }

    // Big operation switch
    Ptr<PCA> obj = obj_[id];
    if (obj.empty())
        mexErrMsgIdAndTxt("mexopencv:error", "Object not found id=%d", id);
    if (method == "delete") {
        nargchk(nrhs==2 && nlhs==0);
        obj_.erase(id);
        mexUnlock();
    }
    else if (method == "read") {
        nargchk(nrhs>=3 && (nrhs%2)==1 && nlhs==0);
        bool loadFromString = false;
        for (int i=3; i<nrhs; i+=2) {
            string key(rhs[i].toString());
            if (key == "FromString")
                loadFromString = rhs[i+1].toBool();
            else
                mexErrMsgIdAndTxt("mexopencv:error",
                    "Unrecognized option %s", key.c_str());
        }
        FileStorage fs(rhs[2].toString(), FileStorage::READ +
            (loadFromString ? FileStorage::MEMORY : 0));
        if (!fs.isOpened())
            mexErrMsgIdAndTxt("mexopencv:error", "Failed to open file");
        obj->read(fs.root());
    }
    else if (method == "write") {
        nargchk(nrhs==3 && nlhs<=1);
        FileStorage fs(rhs[2].toString(), FileStorage::WRITE +
            ((nlhs > 0) ? FileStorage::MEMORY : 0));
        if (!fs.isOpened())
            mexErrMsgIdAndTxt("mexopencv:error", "Failed to open file");
        obj->write(fs);
        if (nlhs > 0)
            plhs[0] = MxArray(fs.releaseAndGetString());
    }
    else if (method == "compute") {
        nargchk(nrhs>=3 && (nrhs%2)==1 && nlhs==0);
        Mat mean;
        int flags = PCA::DATA_AS_ROW;
        int maxComponents = 0;
        double retainedVariance = 1.0;
        bool use_second_variant = false;
        for (int i=3; i<nrhs; i+=2) {
            string key(rhs[i].toString());
            if (key == "Mean")
                mean = rhs[i+1].toMat();
            else if (key == "DataAs")
                flags = DataAs[rhs[i+1].toString()];
            else if (key == "MaxComponents")
                maxComponents = rhs[i+1].toInt();
            else if (key == "RetainedVariance") {
                retainedVariance = rhs[i+1].toDouble();
                use_second_variant = true;
            }
            else
                mexErrMsgIdAndTxt("mexopencv:error",
                    "Unrecognized option %s", key.c_str());
        }
        Mat data(rhs[2].toMat());
        if (use_second_variant)
            obj->operator()(data, mean, flags, retainedVariance);
        else
            obj->operator()(data, mean, flags, maxComponents);
    }
    else if (method == "project") {
        nargchk(nrhs==3 && nlhs<=1);
        plhs[0] = MxArray(obj->project(rhs[2].toMat()));
    }
    else if (method == "backProject") {
        nargchk(nrhs==3 && nlhs<=1);
        plhs[0] = MxArray(obj->backProject(rhs[2].toMat()));
    }
    else if (method == "get") {
        nargchk(nrhs==3 && nlhs<=1);
        string prop(rhs[2].toString());
        if (prop == "eigenvectors")
            plhs[0] = MxArray(obj->eigenvectors);
        else if (prop == "eigenvalues")
            plhs[0] = MxArray(obj->eigenvalues);
        else if (prop == "mean")
            plhs[0] = MxArray(obj->mean);
        else
            mexErrMsgIdAndTxt("mexopencv:error",
                "Unrecognized property %s", prop.c_str());
    }
    else if (method == "set") {
        nargchk(nrhs==4 && nlhs==0);
        string prop(rhs[2].toString());
        if (prop == "eigenvectors")
            obj->eigenvectors = rhs[3].toMat();
        else if (prop == "eigenvalues")
            obj->eigenvalues = rhs[3].toMat();
        else if (prop == "mean")
            obj->mean = rhs[3].toMat();
        else
            mexErrMsgIdAndTxt("mexopencv:error",
                "Unrecognized property %s", prop.c_str());
    }
    else
        mexErrMsgIdAndTxt("mexopencv:error",
            "Unrecognized operation %s", method.c_str());
}