import sensor, image, time,pyb

yellow_threshold   =(0, 100, -128, 127, 47, 21)

RED_LED_PIN = 1

BLUE_LED_PIN = 3

sensor.reset() # Initialize the camera sensor.

sensor.set_pixformat(sensor.RGB565) # use RGB565.

sensor.set_framesize(sensor.QQVGA) # use QQVGA for speed.

sensor.skip_frames(30) # Let new settings take affect.

sensor.set_auto_whitebal(False) # turn this off.

#关闭白平衡。白平衡是默认开启的，在颜色识别中，需要关闭白平衡。

clock = time.clock() # Tracks FPS.

while(True):

    clock.tick() # Track elapsed milliseconds between snapshots().

    img = sensor.snapshot() # Take a picture and return the image.

    blobs = img.find_blobs([yellow_threshold])

    if blobs:

    #如果找到了目标颜色

        for b in blobs:

        #迭代找到的目标颜色区域

            # Draw a rect around the blob.

            img.draw_rectangle(b[0:4]) # rect

            #用矩形标记出目标颜色区域

            img.draw_cross(b[5], b[6]) # cx, cy

            #在目标颜色区域的中心画十字形标记

            print(b[5], b[6])

            print("You're on camera!")

            pyb.LED(BLUE_LED_PIN).on()

            img = sensor.snapshot()

            img.save("example2.jpg") # or "example.bmp" (or others)

            pyb.LED(BLUE_LED_PIN).off()

            print("Done! Reset the camera to see the saved image.")



    print(clock.fps()) # Note: Your OpenMV Cam runs about half as fast while

    # connected to your computer. The FPS should increase once disconnected.
![0_1565325296686_无标题.png](https://fcdn.singtown.com/f04121f5-96fc-4bfb-b36b-fbf7ebc8d4e1.png) 

import sensor, image, time,pyb

yellow_threshold   =(0, 100, -128, 127, 47, 21)

RED_LED_PIN = 1
BLUE_LED_PIN = 3

sensor.reset() # Initialize the camera sensor.

sensor.set_pixformat(sensor.RGB565) # use RGB565.

sensor.set_framesize(sensor.QQVGA) # use QQVGA for speed.

sensor.skip_frames(10) # Let new settings take affect.

#红灯亮
pyb.LED(RED_LED_PIN).on()
sensor.skip_frames(30) # Give the user time to get ready.

#红灯灭，蓝灯亮
pyb.LED(RED_LED_PIN).off()
pyb.LED(BLUE_LED_PIN).on()


sensor.set_auto_whitebal(False) # turn this off.

#关闭白平衡。白平衡是默认开启的，在颜色识别中，需要关闭白平衡。

clock = time.clock() # Tracks FPS.

while(True):

    clock.tick() # Track elapsed milliseconds between snapshots().

    img = sensor.snapshot() # Take a picture and return the image.

    blobs = img.find_blobs([yellow_threshold])

    if blobs:

    #如果找到了目标颜色

        for b in blobs:

        #迭代找到的目标颜色区域

            # Draw a rect around the blob.

            img.draw_rectangle(b[0:4]) # rect

            #用矩形标记出目标颜色区域

            img.draw_cross(b[5], b[6]) # cx, cy

            #在目标颜色区域的中心画十字形标记

            print(b[5], b[6])
            
            print("You're on camera!")
            
            sensor.snapshot().save("example.jpg") # or "example.bmp" (or others)

            pyb.LED(BLUE_LED_PIN).off()
            
            print("Done! Reset the camera to see the saved image.")



    print(clock.fps()) # Note: Your OpenMV Cam runs about half as fast while

    # connected to your computer. The FPS should increase once disconnected.