THRESHOLD = (0, 45, 19, -100, -24, 27) # Grayscale threshold for dark things...
roi1=  [(0,0,80,60),
        (26,45,25,11),#down
         (61,27,16,8)]#right
n=0
a=0
import sensor, image, time
from pyb import LED

#LED(1).on()
#LED(2).on()
#LED(3).on()

sensor.reset()
#sensor.set_vflip(True)#垂直翻转
#sensor.set_hmirror(True)#打开水平镜像
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QQVGA) # 80x60 (4,800 pixels) - O(N^2) max = 2,3040,000.
sensor.set_windowing([0,0,80,60])
sensor.skip_frames(time = 2000)     # WARNING: If you use QQVGA it may take seconds
clock = time.clock()                # to process a frame sometimes.

while(True):
    clock.tick()
    down_flag=right_flag=0
    img = sensor.snapshot().binary([THRESHOLD])#阈值进行二进制
    line = img.get_regression([(100,100)], robust = True)#线性回归计算
    for rec in roi1:
            img.draw_rectangle(rec, color=(255,0,0))#颜色
    if (line):
        rho_err = abs(line.rho())-img.width()/2
        if line.theta()>90:
            theta_err = line.theta()-180
        else:
            theta_err = line.theta()
        img.draw_line(line.line(), color = 127)#画线
        #print(rho_err,line.magnitude(),rho_err)
        if img.find_blobs([(0, 45, 19, -100, -24, 27)],roi=(26,45,25,11)):
            down_flag=1
            n=1
            print(n)
            if img.find_blobs([(0, 45, 19, -100, -24, 27)],roi=(61,27,16,8)):
             right_flag=1
             a=2
             print(a)