docstr: Generate center line by poly clock-wise point. (4, 2)
docstr_tok: ["Generate","center","line","by","poly","clock-wise","point",".","(","4",",","2",")"]
code: def quad2tcl(self, poly, ratio):
      """
      Generate center line by poly clock-wise point. (4, 2)
      """
      ratio_pair = np.array(
          [[0.5 - ratio / 2], [0.5 + ratio / 2]], dtype=np.float32
      )
      p0_3 = poly[0] + (poly[3] - poly[0]) * ratio_pair
      p1_2 = poly[1] + (poly[2] - poly[1]) * ratio_pair
      return np.array([p0_3[0], p1_2[0], p1_2[1], p0_3[1]])
  
imports: import math
  import cv2
  import numpy
  import json
  import sys
  import os
label_desc: Use image node_id 19 for calling the SASTProcessTrain obj's underlying member method code with example usage: obj.quad2tcl(poly, ratio) and returns: np