Draw no loops in OpenCV

dnl.py

#!/usr/bin/env python

'''
Draw no loops in OpenCV

Usage:
------
    dnl.py [<video source>]    

Keys:
-----
    ESC   - exit

'''

import sys
import numpy as np
import cv2
from functools import reduce

class DrawNoLoops:
    def __init__(self):
        self.frame = None
        self.font = cv2.FONT_HERSHEY_SIMPLEX

    def draw_points(self, tmp, xy):
        # Method for drawing points
        cv2.drawMarker(self.frame, np.int32(xy), (0,255,0), 1, 15, 1, 8)
        cv2.putText(frame, str(xy[0])+':'+str(xy[1]), np.int32(xy), self.font, 0.3, (255,0,0), 1)

    def draw_frame(self, frame, points):
        # Method based on the reduce function
        self.frame = frame
        reduce(self.draw_points, points)

if __name__ == '__main__':
    print(__doc__)

    import sys
    try:
        video_src = sys.argv[1]
    except:
        video_src = 0

    cap = cv2.VideoCapture(video_src)
    window_name = 'DrawNoloops'
    cv2.namedWindow(window_name, cv2.WINDOW_GUI_NORMAL | cv2.WINDOW_AUTOSIZE)
    cv2.setWindowTitle(window_name, window_name)

    detector = cv2.FastFeatureDetector_create(threshold=10, nonmaxSuppression=True)

    dnl = DrawNoLoops()

    while True:
        src, frame = cap.read()
        if frame is None:
            break

        kp = detector.detect(frame, None)
        points = cv2.KeyPoint_convert(kp)

        dnl.draw_frame(frame, points)

        # # The old loop method
        # for xy in points:
        #     cv2.drawMarker(frame, np.int32(xy), (0,255,0), 1, 15, 1, 8)
        #     cv2.putText(frame, str(xy[0])+':'+str(xy[1]), np.int32(xy), cv2.FONT_HERSHEY_SIMPLEX, 0.3, (255,0,0), 1)

        cv2.imshow(window_name, frame)
        ch = cv2.waitKey(1)
        if ch == 27:
            break

    cap.release()
    cv2.destroyAllWindows()

ReduceDraw.py

class ReduceDraw:
    """
    Class for drawing many objects without loops
    """
    __slots__ = ['frame_tmp','color', 'size', 'font']
    def __init__(self, color = (0, 0, 255), size = 10):
        self.frame_tmp = None
        self.color = color
        self.size = size
        self.font = cv2.FONT_HERSHEY_SIMPLEX

    def _draw_markers(self, tmp, pt):
        """ Method that the reduce function is called """
        cv2.drawMarker(self.frame_tmp,
            tuple(map(np.int32, pt)),
            self.color, 1, self.size, 1, 8)

    def draw_markers(self, frame, kp):
        """ Method for draw key points """
        self.frame_tmp = frame
        reduce(self._draw_markers, [pt for pt in cv2.KeyPoint_convert(kp)])

    def _draw_descriptors(self, tmp, kp):
        # if kp.response>0.00001:
        p2x = kp.pt[0] + kp.size * np.cos(kp.angle * np.pi / 180.0)
        p2y = kp.pt[1] + kp.size * np.sin(kp.angle * np.pi / 180.0)
        cv2.line(self.frame_tmp, np.int32(kp.pt), tuple(map(np.int32, kp.pt)), cc.red, 1)
        cv2.circle(self.frame_tmp, np.int32(kp.pt), np.int32(kp.size), cc.green, 1)
        cv2.putText(self.frame_tmp, str(kp.class_id), np.int32(kp.pt), self.font , 0.3, cc.yellow, 1)

    def draw_descriptors(self, frame, kp):
        """ Draw info by descriptors (kp - KeyPoint, des -  Detector) """
        self.frame_tmp = frame
        reduce(self._draw_descriptors, [pt for pt in kp])

    def set_color(self, color):
        self.color = color

    def set_size(self, size):
        self.size = size