while(True):
clock.tick()
img = sensor.snapshot()
for tag in img.find_apriltags(families=tag_families):
print(img.size())
img.draw_string(tag.cx()-65,tag.cy()+20, "TAG ID = %d"%tag.id(), color = (0), scale = 3, mono_space = False)
if tag.id() == 8 :这里用if筛选一下