Function cannyHelper

src/api/c/canny.cpp:199–222

template<typename T>
af_array cannyHelper(const Array<T>& in, const float t1,
                     const af_canny_threshold ct, const float t2,
                     const unsigned sw, const bool isf) {
    static const vector<float> v{-0.11021f, -0.23691f, -0.30576f, -0.23691f,
                                 -0.11021f};
    Array<float> cFilter = createHostDataArray<float>(dim4(5, 1), v.data());
    Array<float> rFilter = createHostDataArray<float>(dim4(1, 5), v.data());

    // Run separable convolution to smooth the input image
    Array<float> smt =
        convolve2<float, float>(cast<float, T>(in), cFilter, rFilter, false);

    auto g          = sobelDerivatives<float, float>(smt, sw);
    Array<float> gx = g.first;
    Array<float> gy = g.second;

    Array<float> gmag = gradientMagnitude(gx, gy, isf);

    Array<float> supEdges = nonMaximumSuppression(gmag, gx, gy);

    auto swpair = computeCandidates(supEdges, t1, ct, t2);

    return getHandle(edgeTrackingByHysteresis(swpair.first, swpair.second));
}

}  // namespace