Function FullProf

jni/stasm/classicdesc.cpp:118–150

// We also use shape for figuring out the direction of the whisker.

static VEC FullProf(          // return full profile
    const Image& img,         // in
    const MAT&   shape,       // in
    int          ipoint,      // in: index of the current point
    int          fullproflen) // in
{
    CV_Assert(fullproflen > 1 && fullproflen < 100); // 100 is arb
    CV_Assert(fullproflen % 2 == 1); // fullprof length must be odd

    VEC fullprof(1, fullproflen);

    double xstep; // x axis dist corresponding to one pixel along whisker
    double ystep;
    WhiskerStep(xstep, ystep, shape, ipoint);

    const double x = shape(ipoint, IX); // center point of the whisker
    const double y = shape(ipoint, IY);

    // number of pixs to sample in each direction along the whisker
    const int n = (NSIZE(fullprof) - 1) / 2;

    int prevpix = Pix(img,
                      Step(x, xstep, -n-1), Step(y, ystep, -n-1));

    for (int i = -n; i <= n; i++)
    {
        const int pix = Pix(img,
                            Step(x, xstep, i), Step(y, ystep, i));
        fullprof(i + n) = double(pix - prevpix); // signed gradient
        prevpix = pix;
    }
    return fullprof;
}

static double SumAbsElems( // return the sum of the abs values of the elems of mat
    const MAT& mat) // in