KOI MicroPython API

Please refer to this page on how to utilize the various functions of the KOI using micropython.

Importing KOI library

from koi import *

Basics

LCD Orientation

lcd.rotation(0)

Changes LCD orientation.

0 for front facing, 1 for back facing.

Drawing Strings

drawString(x, y, string, delay)

Draws a string on the LCD.

X, Y: Coordinates represent top left corner of string.
String: String.
Delay: Text duration.

Taking and showing pictures

img.save("s1.jpg")
loadImage("s1.jpg")

Taking and showing pictures.

Getting button values

btnAValue()
btnBValue()

Obtains button values.

Returns 1 when pressed, 0 when not pressed.

Sample Program

#/bin/python
from koi import *

from time import sleep

x = 0

lcd.rotation(2)     #Change LCD orientation
sleep(1)
lcd.rotation(0)     #Change LCD orientation
sleep(1)
drawString(5,5,"hello world",500)       #Show String
while True:
  img=sensor.snapshot()     #Enables screen refresh
  lcd.display(img)          #Enables screen refresh
  if btnAValue() == 1:
    img.save("s1.jpg")      #Takes picture
  if btnBValue() == 1:
    loadImage("s1.jpg")     #Shows picture

Image Classifier

Initiate Classifier

cla.reset()

Initiates the classifier.

Feature extraction

cla.addImage("tag")

Extract features and add tag.

tag: object name, maximum 40 items, 40 pictures

Image Classifying

cla.getImageTag()

Classify the image, returns tag.

Classifier Event Triggers

while cla.getImageTag()=='tag':
    pass

Triggers an event on classification.

Saving and Loading Classifier Models

cla.save("abc.json")
cla.load("abc.json")

Save or load classifier models.

Sample Program

#Model Training
from koi import *

x=0

cla.reset()     #Init classifier

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        cla.addImage('apple')       #Add tag
    if btnBValue():
        cla.addImage('orange')      #Add tag
    if btnAValue() and btnBValue():
        cla.save('fruit.json')      #Save Model
    time.sleep(0.1)

#Model Running
from koi import *

x=0
cla.reset()         #init classifier
cla.load("fruit.json")      #Load Model

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        tag=cla.getImageTag()       #Classify
        if tag=='orange':
            print('I like oranges.')
        elif tag=='apple':
            print('Apples are healthy.')
    time.sleep(0.1)

Face Detection

Load Face Model

yoloinit()

Load face model.

Track face

trackface()

Tracks the face, returns a list.

示範程式

#/bin/python
from koi import *

x = 0
face_prop=[0,0]

yoloinit()          #Load Face model
while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    r = trackface()         #Tracks the face
    if r:
        is_face=1
        drawString(5,5,r,500)
        face_prop[0]=(r[0][2]+r[0][0])/2
        face_prop[1]=(r[0][3]+r[0][1])/2
    else:
        is_face=0
        
    while is_face:
        print('X: '+str(face_prop[0]))
        print('Y: '+str(face_prop[1]))
        is_face=0
    time.sleep(0.5)

Geometric Shape Tracking

Track Lines

findLines()

Find lines, returns a list.

Track Circles

findCircle(threshold)

Find circles, returns a list.

threshold: adjust this value to adjust sensitivity, default is 4000.

Track Rectangles

findRect(threshold)

Find rectangles, returns a list.

threshold: adjust this value to adjust sensitivity, default is 4000.

Sample Program

from koi import *

x=0

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue() and btnBValue():
        line_prop = findLines()     #Find lines
        print(line_prop[0])
        time.sleep(0.1)
    elif btnAValue():
        circle_prop = findCircle(4000)    #Find Circles
        print(circle_prop[0])
        time.sleep(0.1)
    elif btnBValue():
        rect_prop = findRects(4000)       #Find Rectangles
        print(rect_prop[0])
        time.sleep(0.1)

Color Blob Tracking

Calibrates Color

colorCalibrate()

Calibrates color for tracking.

Finds Color Blob

findBlob()

Finds color blob, returns a list.

Finds Line

findLinearRegress()

Finds line, returns a list.

Sample Program

from koi import *

x=0

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        colorCalibrate()        #Color Calibration
        time.sleep(0.1)
    elif btnBValue():
        blob_prop=findBlob()        # Finds Color Blob  
        print(blob_prop[0])
        time.sleep(0.1)
    elif btnAValue() and btnBValue():
        line_prop=findLinearRegress()       #Finds Line
        print(line_prop[0])
        time.sleep(0.1)

Barcode and QR code Recognition

QR Code Recognition

findQRCode()

Finds QR code, returns content of QR code.

Barcode Recognition

findBarcode()

Finds Barcode, returns content of barcode.

AprilTag Recognition

findAprilTag()

Finds Apriltag, returns content of Apriltag.

Sample Program

from koi import *

x=0

lcd.rotation(2)

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        barcode=findBarCode()       #Barcode
        print(barcode[0][4])
        time.sleep(0.1)
    if btnBValue():
        qrcode=findQRCode()     #QR Code
        print(qrcode[0][4])
        time.sleep(0.1)
    if btnAValue() and btnBValue():
        april=findAprilTag()        #AprilTag
        print(april[0])
        time.sleep(0.1)

Voice Recognition

Record and Play

speech.recordWav('hi.wav')
speech.playWav('hi.wav')

Records and plays a wav file.

Calibrates Noise Level

speech.noiseTap()

Calibrates the noise level, mandatory before voice recognition.

Adds Voice Command

speech.addCommand('hi')

Adds a voice command.

Recognizes Voice Command

speech.getCommand()

Recognizes and returns the command.

Saves Voice Model

speech.saveClass('name.json')

Saves the voice model.

Loads Voice Model

speech.loadClass('name.json')

Loads the voice model.

Sample Program

# Rec and Play
from koi import *

x=0

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        speech.recordWav('hi.wav')      #Record
        time.sleep(0.1)
    if btnBValue():
        speech.playWav('hi.wav')        #Play
        time.sleep(0.1)

#Voice Recognition
from koi import *

x=0

speech.noiseTap()       #Calibrate

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        speech.addCommand("hello")      #Add command
        time.sleep(0.1)
    if btnBValue():
        speech.addCommand("bye")    #Add command
        time.sleep(0.1)
    if btnAValue() and btnBValue():
        print(speech.getCommand())      #Recognize
        time.sleep(0.1)

IoT

Connecting to WiFi

wifi.joinap(str("apname"),str("password"))

Connects to WiFi.

IP Address

wifi.ipaddr()

Return IP address.

Connects to MQTT Broker.

wifi.mqtthost(host)

Connects to MQTT Broker.

host: MQTT host address

Subscribes Topic

wifi.mqttsub(topic)

Subscribes a topic on MQTT.

topic: topic to subscribe

Publishes Message to Topic

wifi.mqttsub(topic, message)

Publishes a message to topic.

topic: topic to publish.
message: message to publish.

Reads MQTT message

wifi.mqttread(topic)

Reads topic message.

topic: topic to read from, returns a list.

Sample Program

from koi import *

wifi.joinap(str("apname"),str("password"))      #WiFi
time.sleep(2)
print(wifi.ipaddr())    #IP
time.sleep(2)
wifi.mqtthost("127.0.0.1")      #MQTT
wifi.mqttsub("test01")      #Subscribe

while True:
    img=sensor.snapshot()    #Enables screen refresh
    lcd.display(img)         #Enables screen refresh
    if btnAValue():
        wifi.mqttpub("test01","hello world")    #Publish
    if btnBValue():
        msg=wifi.mqttread("test01")     #Read
        print("Message: "+msg[0])
        print("Topic: "+msg[1])

Face Recognition

face=baiduFace(op=1)

Runs face recognition once.(WiFi required)

Face Parameters

face['parameter']

Returns result from face recognition.

parameter:

face_token: unique face token for each face
location: coordinates, size of face
gender: gender of person
expression: emotion of person
angle: tilt angle of face
mask: true if person is wearing a mask
age: age of person

Adding Faces to a Group

baiduFace(op=2, token=face['face_token'], group="group", name="name")

Adds a face to the face group.

Searching Faces from a Group

baiduFace(op=3, token=face['face_token'], group="group")

Searches a face from a group, returns name and confidence.

Sample Program

from koi import *

wifi.joinap(str("apname"),str("password"))
time.sleep(2)

while True:
    img=sensor.snapshot()   #Enables screen refresh
    lcd.display(img)        #Enables screen refresh
    if btnAValue():
        face=baiduFace(op=1)
        time.sleep(5)
        baiduFace(op=2, token=face['face_token'], group="group", name="name")   #add face
    if btnBValue():
        face=baiduFace(op=1)
        time.sleep(5)
        result=baiduFace(op=3, token=face['face_token'], group="name")  #search face
        print("Name: "+faceResult['result']['user_list'][0]['user_id'])
        print("Confidence: "+str(faceResult['result']['user_list'][0]['score']))

KOI MicroPython API

Importing KOI library

Basics

LCD Orientation

Drawing Strings

Taking and showing pictures

Getting button values

Sample Program

Image Classifier

Initiate Classifier

Feature extraction

Image Classifying

Classifier Event Triggers

Saving and Loading Classifier Models

Sample Program

Face Detection

Load Face Model

Track face

示範程式

Geometric Shape Tracking

Track Lines

Track Circles

Track Rectangles

Sample Program

Color Blob Tracking

Calibrates Color

Finds Color Blob

Finds Line

Sample Program

Barcode and QR code Recognition

QR Code Recognition

Barcode Recognition

AprilTag Recognition

Sample Program

Voice Recognition

Record and Play

Calibrates Noise Level

Adds Voice Command

Recognizes Voice Command

Saves Voice Model

Loads Voice Model

Sample Program

IoT

Connecting to WiFi

IP Address

Connects to MQTT Broker.

Subscribes Topic

Publishes Message to Topic

Reads MQTT message

Sample Program

Face Recognition

Face Recognition

Face Parameters

Adding Faces to a Group

Searching Faces from a Group

Sample Program

Q&A

KOI’s display is laggy.

Please enable the screen refresh.

KOI does not run the program I uploaded.

Please restart the KOI because it was still running the original main.py.

Can I connect other modules using the 4-Pin Port?

No, this port is for connecting to Micro:bit only.

KOI’s LCD is reversed.

Please use the LCD orientation command.