麻烦问一下，运行老是出现图片上的提示，这是什么问题

[4qgd]

import sensor, image, time, lcd
import json
from pyb import UART
green_threshold   = (41, 66, -61, -27, 8, 43)
red_threshold   = (41, 61, 42, 127, -128, 127)
yellow_threshold   = ( 60 ,10,-15,20,30,80)
sensor.set_hmirror(True)
sensor.set_vflip(True)
sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QQVGA2)
sensor.skip_frames(10)
sensor.set_auto_whitebal(False)

clock = time.clock()
lcd.init() # Initialize the lcd screen.

uart = UART(3, 9600)
def find_max(blobs):
    max_size=0
    for blob in blobs:
       if blob.pixels() > max_size:
            max_blob=blob
            max_size = blob.pixels()
    return max_blob
while(True):

    
    clock.tick()
    

    img = sensor.snapshot()
    blobs0 = img.find_blobs([green_threshold])
    blobs1 = img.find_blobs([red_threshold])
    blobs2 = img.find_blobs([yellow_threshold])
    if blobs0:
     max_blob=find_max(blobs0)
     img.draw_rectangle(max_blob.rect())
     img.draw_cross(max_blob.cx(), max_blob.cy())
     img.draw_string(100,100, 'x=' + str(blobs0.cx()), color=(0,0,0))
     img.draw_string(100,120, 'y=' + str(blobs0.cy()), color=(0,0,0))
 
   
     data="0"
     data_out = json.dumps(set(data))
     uart.write(data_out +'\n')
     print('you send:',data_out)
     
    elif blobs1:
     max_blob=find_max(blobs1)
     img.draw_rectangle(max_blob.rect())
     img.draw_cross(max_blob.cx(), max_blob.cy())
     data="1"
     data_out = json.dumps(set(data))
     uart.write(data_out +'\n')
     print('you send:',data_out)
    elif blobs2:
     max_blob=find_max(blobs2)
     img.draw_rectangle(max_blob.rect())
     img.draw_cross(max_blob.cx(), max_blob.cy())
     data="2"
     data_out = json.dumps(set(data))
     uart.write(data_out +'\n')
     print('you send:',data_out)
    else:
        print('not found','4')
   
    
    lcd.display(img) # Take a picture and display the image.

[kidswong999]

40行：blobs0.cx() 改为max_blob.cx()
41行：blobs0.cy() 改为max_blob.cy()