Skip to main content

3. Barcode Recognition Experiment

wmnologoAbout 1 min

Routine Code

import sensor, image, time, math, lcd

lcd.init()
sensor.reset()
sensor.set_pixformat(sensor.RGB565) #GRAYSCALE
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 100)
sensor.set_auto_gain(False)
sensor.set_auto_whitebal(False)
clock = time.clock()

def barcode_name(code):
    if(code.type() == image.EAN2):
        return "EAN2"
    if(code.type() == image.EAN5):
        return "EAN5"
    if(code.type() == image.EAN8):
        return "EAN8"
    if(code.type() == image.UPCE):
        return "UPCE"
    if(code.type() == image.ISBN10):
        return "ISBN10"
    if(code.type() == image.UPCA):
        return "UPCA"
    if(code.type() == image.EAN13):
        return "EAN13"
    if(code.type() == image.ISBN13):
        return "ISBN13"
    if(code.type() == image.I25):
        return "I25"
    if(code.type() == image.DATABAR):
        return "DATABAR"
    if(code.type() == image.DATABAR_EXP):
        return "DATABAR_EXP"
    if(code.type() == image.CODABAR):
        return "CODABAR"
    if(code.type() == image.CODE39):
        return "CODE39"
    if(code.type() == image.PDF417):
        return "PDF417"
    if(code.type() == image.CODE93):
        return "CODE93"
    if(code.type() == image.CODE128):
        return "CODE128"

while(True):
    clock.tick()
    img = sensor.snapshot()
    fps = clock.fps()
    codes = img.find_barcodes()
    for code in codes:
        img.draw_rectangle(code.rect(), color=(0, 255, 0))
        print_args = (barcode_name(code), code.payload(), (180 * code.rotation()) / math.pi, code.quality())
        print("Barcode %s, Payload \"%s\", rotation %f (degrees), quality %d" % print_args)
    img.draw_string(0, 0, "%2.1ffps" %(fps), color=(0, 60, 128), scale=2.0)
    lcd.display(img)

Experiment Preparation

    1. Connect the K210 to your computer via USB.
    1. Prepare a barcode.
    1. 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 barcode and it will be outlined.
    1. Barcode information is 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, math, lcd

lcd.init()
sensor.reset()
sensor.set_pixformat(sensor.RGB565) #GRAYSCALE 
sensor.set_framesize(sensor.QVGA)
sensor.skip_frames(time = 100) 
sensor.set_auto_gain(False)
sensor.set_auto_whitebal(False) 
clock = time.clock()
    1. Convert barcode type names to strings.
def barcode_name(code):
    if(code.type() == image.EAN2):
        return "EAN2"
    if(code.type() == image.EAN5):
        return "EAN5"
    if(code.type() == image.EAN8):
        return "EAN8"
    if(code.type() == image.UPCE):
        return "UPCE"
    if(code.type() == image.ISBN10):
        return "ISBN10"
    if(code.type() == image.UPCA):
        return "UPCA"
    if(code.type() == image.EAN13):
        return "EAN13"
    if(code.type() == image.ISBN13):
        return "ISBN13"
    if(code.type() == image.I25):
        return "I25"
    if(code.type() == image.DATABAR):
        return "DATABAR"
    if(code.type() == image.DATABAR_EXP):
        return "DATABAR_EXP"
    if(code.type() == image.CODABAR):
        return "CODABAR"
    if(code.type() == image.CODE39):
        return "CODE39"
    if(code.type() == image.PDF417):
        return "PDF417"
    if(code.type() == image.CODE93):
        return "CODE93"
    if(code.type() == image.CODE128):
        return "CODE128"
    1. Create a while loop to analyze barcodes in the camera feed. If a barcode is found, print its information and outline it in green.
while(True):
    clock.tick()
    img = sensor.snapshot()
    fps = clock.fps()
    codes = img.find_barcodes()
    for code in codes:
        img.draw_rectangle(code.rect(), color=(0, 255, 0))
        print_args = (barcode_name(code), code.payload(), (180 * code.rotation()) / math.pi, code.quality())
        print("Barcode %s, Payload \"%s\", rotation %f (degrees), quality %d" % print_args)
    img.draw_string(0, 0, "%2.1ffps" %(fps), color=(0, 60, 128), scale=2.0)
    lcd.display(img)
Copyright © 2026 wmnologo