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    connect_label = connect_output[1]

    # connect_data = [[leftmost (x), topmost (y), horizontal size, vertical size, total area in pixels], ...]

    connect_data = connect_output[2]

    connect_data[connect_data[:, 0] >= mat.shape[1]] = 0   # ?

    connect_data[connect_data[:, 1] >= mat.shape[0]] = 0   # ?

    connect_data[connect_data[:, 0] >= mat.shape[1]] = 0   # clear connected components out of bound

    connect_data[connect_data[:, 1] >= mat.shape[0]] = 0   # clear connected components out of bound 

    if MODE == D:

        print("connected components num: " + str(len(connect_output[2])))

    # We can first crop this component from label map according to component info

    # This use something like np.argmin, np.argmax

    bar_peak_point = []

    for i in range(len(connect_remain)):

        top_y = connect_remain[i][1]

        top_x_series = np.where(connect_label[top_y + 1, connect_remain[i][0]:connect_remain[i][0] + connect_remain[i][2]] != 0)[0]

    for i in range(len(connect_remain)):# connect_remain: data tuple of remained connecetd components

        top_y = connect_remain[i][1] # top y coordinate of connecetd components

        top_x_series = np.where(connect_label[top_y + 1, connect_remain[i][0]:connect_remain[i][0] + connect_remain[i][2]] != 0)[0] # locate a sereis of x coordinate of the light bar # Unsure: why first y, then x ? why only keep index[0] ? 

        if len(top_x_series) == 0:

            return []

        n1 = int((np.max(top_x_series) + np.min(top_x_series)) / 2 + connect_remain[i][0])

        down_y = connect_remain[i][1] + connect_remain[i][3] - 1

        down_x_series = np.where(connect_label[down_y - 1, connect_remain[i][0]:connect_remain[i][0] + connect_remain[i][2]] != 0)[0]

        n1 = int((np.max(top_x_series) + np.min(top_x_series)) / 2 + connect_remain[i][0]) # x coordinate of mid point of top line of light bar 

        down_y = connect_remain[i][1] + connect_remain[i][3] - 1 # y coordinate of bottom line of light bar 

        down_x_series = np.where(connect_label[down_y - 1, connect_remain[i][0]:connect_remain[i][0] + connect_remain[i][2]] != 0)[0] # series of x coordinate of bottom line of light bar 

        if len(down_x_series) == 0:

            return []

        n2 = int((np.max(down_x_series) + np.min(down_x_series)) / 2 + connect_remain[i][0])

        bar_peak_point.append([n1, top_y, n2, down_y, connect_remain[i][4]])

        n2 = int((np.max(down_x_series) + np.min(down_x_series)) / 2 + connect_remain[i][0]) # x coordinate of mid point of bottom line of light bar s

        bar_peak_point.append([n1, top_y, n2, down_y, connect_remain[i][4]]) #FIXME # Should be [top_mid_x, top_mid_y, down_mid_x, down_mid_y, pixel count]

    # bar_peak_point [[top_left_x, top_left_y, down_right_x, down_right_y, pixel count], ...]

    bar_peak_point = np.array(bar_peak_point)