cnn_prediction.py 文件源码

def _drawSpeed(image, speed, frameHeight=480, frameWidth=640):
  maxBars = 8
  numBars = min(int(speed/6)+1, maxBars)  # 6 m/s per speed bar
  for i in xrange(maxBars):
    overlay = image.copy()
    color = (10, 42*i, 42*(maxBars-1-i))  # BGR
    cv2.rectangle(
        overlay, (i*20, frameHeight-i*10),
        (frameWidth-i*20, frameHeight-(i+1)*10), color, thickness=-1)
    opacity = 0.08
    cv2.addWeighted(overlay, opacity, image, 1-opacity, 0, image)
    if i <= numBars:
      # Shade bars to represent the speed
      opacity = 0.4
      cv2.addWeighted(overlay, opacity, image, 1-opacity, 0, image)