视觉|Apriltag使用之一（python下的安装与检测）机器人|Python

安装在python中有几个实现的apriltag包。在windows下：

pip install pupil-apriltags

【视觉|Apriltag使用之一（python下的安装与检测）】在linux下：

pip install apriltag

简单示例示例一这个例子中读取一个图像文件并进行检测

#!/usr/bin/env python # coding: UTF-8 import apriltag #import pupil_apriltags as apriltag# for windows import cv2 import numpy as np import sysimg =cv2.imread("apriltag_image.jpg") gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY) # 创建一个apriltag检测器 at_detector = apriltag.Detector(apriltag.DetectorOptions(families='tag36h11 tag25h9') ) # at_detector = apriltag.Detector(families='tag36h11 tag25h9')#for windows # 进行apriltag检测，得到检测到的apriltag的列表 tags = at_detector.detect(gray) print("%d apriltags have been detected."%len(tags)) for tag in tags: cv2.circle(img, tuple(tag.corners[0].astype(int)), 4,(255,0,0), 2) # left-top cv2.circle(img, tuple(tag.corners[1].astype(int)), 4,(255,0,0), 2) # right-top cv2.circle(img, tuple(tag.corners[2].astype(int)), 4,(255,0,0), 2) # right-bottom cv2.circle(img, tuple(tag.corners[3].astype(int)), 4,(255,0,0), 2) # left-bottomcv2.imshow("apriltag_test",img) cv2.waitKey()

其中获得的apriltag码的四个顶点可以通过homography变换到标准apriltag码的(-1，1),(1,1),(1,-1),(-1,-1)顶点。

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示例二这个示例中，我们持续读取来自摄像头的图像，检测其中的apriltag，并进行动态的显示

#!/usr/bin/env python # coding: UTF-8 import apriltag #import pupil_apriltags as apriltag# for windows import cv2 import numpy as npcap = cv2.VideoCapture(0) at_detector = apriltag.Detector(apriltag.DetectorOptions(families='tag36h11 tag25h9') ) # at_detector = apriltag.Detector(families='tag36h11 tag25h9')#for windowsi=0 while(1): # 获得图像 ret, frame = cap.read() # 检测按键 k=cv2.waitKey(1) if k==27: break elif k==ord('s'): cv2.imwrite('E:/OpenCV_pic/'+str(i)+'.jpg', frame) i+=1 # 检测apriltag gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) tags = at_detector.detect(gray) for tag in tags: cv2.circle(frame, tuple(tag.corners[0].astype(int)), 4, (255, 0, 0), 2) # left-top cv2.circle(frame, tuple(tag.corners[1].astype(int)), 4, (255, 0, 0), 2) # right-top cv2.circle(frame, tuple(tag.corners[2].astype(int)), 4, (255, 0, 0), 2) # right-bottom cv2.circle(frame, tuple(tag.corners[3].astype(int)), 4, (255, 0, 0), 2) # left-bottom # 显示检测结果 cv2.imshow('capture', frame)cap.release() cv2.destroyAllWindows()

当运行这个代码对tag16h5的apriltag码进行检测时，可以看到显示的图像上会有假的apriltag出现：