Label max_label

[xinsuinizhuan]

what's the meaning of the Lable?
I don't know how to give the the value to max_lable in below function? the test example is outdata

    /// \brief Label the connected parts of a binary image.
    /// Simple, fast algorithm. Does not compute contours.
    /// \param img Input binary image (type = CV_8UC1).
    void SimpleLabel(const cv::Mat &img, Label max_label);

    /// \brief Label the connected parts of a binary image.
    /// Algorithm based on paper "A linear-time component-labeling algorithm using contour tracing technique" of Fu Chang, Chun-Jen Chen and Chi-Jen Lu.
    /// \param img Input binary image (type = CV_8UC1).
    void LabelImage (const cv::Mat &img, Label max_label);