4. QR Code Recognition Experiment

Routine Code

import sensor, image, time, lcd

lcd.init()
sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 100)

clock = time.clock()
while(True):
    clock.tick()
    img = sensor.snapshot()
    for code in img.find_qrcodes():
        img.draw_rectangle(code.rect(), color = 127, thickness=3)
        img.draw_string(code.x(),code.y()-20,code.payload(),color=(255,0,0),scale=2)
        print(code)
    lcd.display(img)
    #print(clock.fps())

Experiment Preparation

• 1. Connect the K210 to your computer via USB.
• 2. Prepare a QR code.
• 3. Open CanMV IDE and run the routine code above.

Experiment Results

• 1. After system initialization completes, the LCD displays the camera feed. Point the camera at a QR code. The QR code is outlined, and its payload is shown in the upper-left corner of the box.

• 2. QR code information is also printed in the Serial Terminal at the bottom of the IDE.

Routine Code Explanation

• 1. Import the required libraries and initialize the camera and LCD display.

import sensor, image, time, lcd

lcd.init()
sensor.reset()
sensor.set_pixformat(sensor.RGB565)
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 100)

• 2. Use the built-in find_qrcodes function to detect QR codes. If found, outline the code and print its information.

clock = time.clock()
while(True):
    clock.tick()
    img = sensor.snapshot()
    for code in img.find_qrcodes():
        img.draw_rectangle(code.rect(), color = 127, thickness=3)
        img.draw_string(code.x(),code.y()-20,code.payload(),color=(255,0,0),scale=2)
        print(code)
    lcd.display(img)
    #print(clock.fps())