为什么find_datamatrices返回的数组是空数组

[r4c3]

import sensor, image, time

sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 2000)
sensor.set_windowing(( 320, 240))

clock = time.clock()



while(True):
    clock.tick()
    img = sensor.snapshot()
    img.lens_corr(1.2)
    matrix = img.find_datamatrices()
    print(matrix)
    print(clock.fps())

[kidswong999]

你的datamatrix的照片是什么？