Category Archives: Tutorial

Raspberry Pi LESSON 37: Raspberry Pi Security System

November 24, 2022 admin

In this lesson we add an audible alarm to our security system. I am connecting to a Bluetooth speaker, and then using the pygame library to play an alarm sound. The pygame library will play any .mp3 file, so search the internet and find a suitable alarm sound for your system. I amusing an air raid siren, and really like it! Below for your convenience is the code we develop in this video:

import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BOARD)
PIRpin=12
GPIO.setup(PIRpin,GPIO.IN)
import LCD1602
import KPLIB
from time import sleep
import threading
myPad=KPLIB.keypad(retChar='D')
LCD1602.init(0x27,1)
myString=''
pwd='1234'

from pygame import mixer
mixer.init()
mixer.music.load('alarm.mp3')

def readKP():
    global myString
    while myString != '*':
        myString=myPad.readKeypad()
        sleep(.5)
readThread=threading.Thread(target=readKP,)
readThread.daemon=True
readThread.start()
while myString != '*':
    CMD=myString
    if CMD=='A'+pwd:
        LCD1602.write(0,0,'Armed          ')
        moveVal=GPIO.input(PIRpin)
        if moveVal==1:
            LCD1602.write(0,1,'Intruder Alert')
            mixer.music.play()
            sleep(10)
        if moveVal==0:
            LCD1602.write(0,1,'All Clear      ')
    if CMD=='B'+pwd:
        LCD1602.write(0,0,'UnArmed        ')
        LCD1602.write(0,1,'               ')
    if CMD=='C'+pwd:
        LCD1602.write(0,0,'Password?      ')
        LCD1602.write(0,1,'               ')
        while myString=='C'+pwd:
            pass
        pwd=myString
        LCD1602.write(0,0,pwd+'         ')
        sleep(2)
        LCD1602.write(0,0,'               ')
        LCD1602.clear()
sleep(1)
GPIO.cleanup()
LCD1602.clear()
print('GPIO Good to Go')

import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BOARD)

PIRpin=12

GPIO.setup(PIRpin,GPIO.IN)

import LCD1602

import KPLIB

from time import sleep

import threading

myPad=KPLIB.keypad(retChar='D')

LCD1602.init(0x27,1)

myString=''

pwd='1234'

from pygame import mixer

mixer.init()

mixer.music.load('alarm.mp3')

def readKP():

global myString

while myString != '*':

myString=myPad.readKeypad()

sleep(.5)

readThread=threading.Thread(target=readKP,)

readThread.daemon=True

readThread.start()

while myString != '*':

CMD=myString

if CMD=='A'+pwd:

LCD1602.write(0,0,'Armed ')

moveVal=GPIO.input(PIRpin)

if moveVal==1:

LCD1602.write(0,1,'Intruder Alert')

mixer.music.play()

sleep(10)

if moveVal==0:

LCD1602.write(0,1,'All Clear ')

if CMD=='B'+pwd:

LCD1602.write(0,0,'UnArmed ')

LCD1602.write(0,1,' ')

if CMD=='C'+pwd:

LCD1602.write(0,0,'Password? ')

LCD1602.write(0,1,' ')

while myString=='C'+pwd:

pass

pwd=myString

LCD1602.write(0,0,pwd+' ')

sleep(2)

LCD1602.write(0,0,' ')

LCD1602.clear()

sleep(1)

GPIO.cleanup()

LCD1602.clear()

print('GPIO Good to Go')

Artificial Intelligence, OpenCV, Python, Tutorial

Improved Gesture Recognition in Python and MediaPipe

February 10, 2022 admin

In this video lesson we show you how you can improve the accuracy of your gesture recognition program developed in the last lesson. We do this by normalizing the hand landmarks distance matrix to a standard size. By doing this, you get accurate results independent of the distance your hand is from the camera. For your convenience, I include the code below which we develop in this lesson. Enjoy!

import time
import cv2
print(cv2.__version__)
import numpy as np

class mpHands:
    import mediapipe as mp
    def __init__(self,maxHands=2,tol1=.5,tol2=.5):
        self.hands=self.mp.solutions.hands.Hands(False,maxHands,tol1,tol2)
    def Marks(self,frame):
        myHands=[]
        frameRGB=cv2.cvtColor(frame,cv2.COLOR_BGR2RGB)
        results=self.hands.process(frameRGB)
        if results.multi_hand_landmarks != None:
            for handLandMarks in results.multi_hand_landmarks:
                myHand=[]
                for landMark in handLandMarks.landmark:
                    myHand.append((int(landMark.x*width),int(landMark.y*height)))
                myHands.append(myHand)
        return myHands
def findDistances(handData):
    distMatrix=np.zeros([len(handData),len(handData)],dtype='float')
    palmSize=((handData[0][0]-handData[9][0])**2+(handData[0][1]-handData[9][1])**2)**(1./2.)
    for row in range(0,len(handData)):
        for column in range(0,len(handData)):
            distMatrix[row][column]=(((handData[row][0]-handData[column][0])**2+(handData[row][1]-handData[column][1])**2)**(1./2.))/palmSize
    return distMatrix

def findError(gestureMatrix,unknownMatrix,keyPoints):
    error=0
    for row in keyPoints:
        for column in keyPoints:
            error=error+abs(gestureMatrix[row][column]-unknownMatrix[row][column])
    print(error)
    return error
def findGesture(unknownGesture,knownGestures,keyPoints,gestNames,tol):
    errorArray=[]
    for i in range(0,len(gestNames),1):
        error=findError(knownGestures[i],unknownGesture,keyPoints)
        errorArray.append(error)
    errorMin=errorArray[0]
    minIndex=0
    for i in range(0,len(errorArray),1):
        if errorArray[i]<errorMin:
            errorMin=errorArray[i]
            minIndex=i
    if errorMin<tol:
        gesture=gestNames[minIndex]
    if errorMin>=tol:
        gesture='Unknown'
    return gesture


width=1280
height=720
cam=cv2.VideoCapture(4,cv2.CAP_DSHOW)
cam.set(cv2.CAP_PROP_FRAME_WIDTH, width)
cam.set(cv2.CAP_PROP_FRAME_HEIGHT,height)
cam.set(cv2.CAP_PROP_FPS, 30)
cam.set(cv2.CAP_PROP_FOURCC,cv2.VideoWriter_fourcc(*'MJPG'))
findHands=mpHands(1)
time.sleep(5)
keyPoints=[0,4,5,9,13,17,8,12,16,20]
train=True
tol=10
trainCnt=0
knownGestures=[]

numGest=int(input('How Many Gestures Do You Want? '))

gestNames=[]

for i in range(0,numGest,1):
    prompt='Name of Gesture #'+str(i+1)+' '
    name=input(prompt)
    gestNames.append(name)
print(gestNames)

while True:
    ignore,  frame = cam.read()
    frame=cv2.resize(frame,(width,height))
    handData=findHands.Marks(frame)
    if train==True:
        if handData!=[]:
            print('Please Show Gesture ',gestNames[trainCnt],': Press t when Ready')
            if cv2.waitKey(1) & 0xff==ord('t'):
                knownGesture=findDistances(handData[0])
                knownGestures.append(knownGesture)
                trainCnt=trainCnt+1
                if trainCnt==numGest:
                    train=False
    if train == False:
        if handData!=[]:
            unknownGesture=findDistances(handData[0])
            myGesture=findGesture(unknownGesture,knownGestures,keyPoints,gestNames,tol)
            #error=findError(knownGesture,unknownGesture,keyPoints)
            cv2.putText(frame,myGesture,(100,175),cv2.FONT_HERSHEY_SIMPLEX,3,(255,0,0),8)
    for hand in handData:
        for ind in keyPoints:
            cv2.circle(frame,hand[ind],25,(255,0,255),3)
    cv2.imshow('my WEBcam', frame)
    cv2.moveWindow('my WEBcam',0,0)
    if cv2.waitKey(1) & 0xff ==ord('q'):
        break
cam.release()

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import time

import cv2

print(cv2.__version__)

import numpy as np

class mpHands:

import mediapipe as mp

def __init__(self,maxHands=2,tol1=.5,tol2=.5):

self.hands=self.mp.solutions.hands.Hands(False,maxHands,tol1,tol2)

def Marks(self,frame):

myHands=[]

frameRGB=cv2.cvtColor(frame,cv2.COLOR_BGR2RGB)

results=self.hands.process(frameRGB)

if results.multi_hand_landmarks != None:

for handLandMarks in results.multi_hand_landmarks:

myHand=[]

for landMark in handLandMarks.landmark:

myHand.append((int(landMark.x*width),int(landMark.y*height)))

myHands.append(myHand)

return myHands

def findDistances(handData):

distMatrix=np.zeros([len(handData),len(handData)],dtype='float')

palmSize=((handData[0][0]-handData[9][0])**2+(handData[0][1]-handData[9][1])**2)**(1./2.)

for row in range(0,len(handData)):

for column in range(0,len(handData)):

distMatrix[row][column]=(((handData[row][0]-handData[column][0])**2+(handData[row][1]-handData[column][1])**2)**(1./2.))/palmSize

return distMatrix

def findError(gestureMatrix,unknownMatrix,keyPoints):

error=0

for row in keyPoints:

for column in keyPoints:

error=error+abs(gestureMatrix[row][column]-unknownMatrix[row][column])

print(error)

return error

def findGesture(unknownGesture,knownGestures,keyPoints,gestNames,tol):

errorArray=[]

for i in range(0,len(gestNames),1):

error=findError(knownGestures[i],unknownGesture,keyPoints)

errorArray.append(error)

errorMin=errorArray[0]

minIndex=0

for i in range(0,len(errorArray),1):

if errorArray[i]<errorMin:

errorMin=errorArray[i]

minIndex=i

if errorMin<tol:

gesture=gestNames[minIndex]

if errorMin>=tol:

gesture='Unknown'

return gesture

width=1280

height=720

cam=cv2.VideoCapture(4,cv2.CAP_DSHOW)

cam.set(cv2.CAP_PROP_FRAME_WIDTH, width)

cam.set(cv2.CAP_PROP_FRAME_HEIGHT,height)

cam.set(cv2.CAP_PROP_FPS, 30)

cam.set(cv2.CAP_PROP_FOURCC,cv2.VideoWriter_fourcc(*'MJPG'))

findHands=mpHands(1)

time.sleep(5)

keyPoints=[0,4,5,9,13,17,8,12,16,20]

train=True

tol=10

trainCnt=0

knownGestures=[]

numGest=int(input('How Many Gestures Do You Want? '))

gestNames=[]

for i in range(0,numGest,1):

prompt='Name of Gesture #'+str(i+1)+' '

name=input(prompt)

gestNames.append(name)

print(gestNames)

while True:

ignore, frame = cam.read()

frame=cv2.resize(frame,(width,height))

handData=findHands.Marks(frame)

if train==True:

if handData!=[]:

print('Please Show Gesture ',gestNames[trainCnt],': Press t when Ready')

if cv2.waitKey(1) & 0xff==ord('t'):

knownGesture=findDistances(handData[0])

knownGestures.append(knownGesture)

trainCnt=trainCnt+1

if trainCnt==numGest:

train=False

if train == False:

if handData!=[]:

unknownGesture=findDistances(handData[0])

myGesture=findGesture(unknownGesture,knownGestures,keyPoints,gestNames,tol)

#error=findError(knownGesture,unknownGesture,keyPoints)

cv2.putText(frame,myGesture,(100,175),cv2.FONT_HERSHEY_SIMPLEX,3,(255,0,0),8)

for hand in handData:

for ind in keyPoints:

cv2.circle(frame,hand[ind],25,(255,0,255),3)

cv2.imshow('my WEBcam', frame)

cv2.moveWindow('my WEBcam',0,0)

if cv2.waitKey(1) & 0xff ==ord('q'):

break

cam.release()

s lesson. Enjoy!

OpenCV, Python, Tutorial

Putting Text, Rectangles and Circles on Images in OpenCV for Windows

August 24, 2021 admin

In the video lesson above we show how to add text, rectangles and circles to video frames using OpenCV. Below we include the code with we developed in this lesson. Enjoy!

import cv2
print(cv2.__version__)
width=640
height=360
myRadius=30
myColor=(0,0,0)
myThick=2
fontH=2
fontT=2
myText='Paul is Boss'
myFont=cv2.FONT_HERSHEY_DUPLEX
upperLeft=(250,140)
lowerRight=(390,220)
lineW=4
cam=cv2.VideoCapture(1,cv2.CAP_DSHOW)
cam.set(cv2.CAP_PROP_FRAME_WIDTH, width)
cam.set(cv2.CAP_PROP_FRAME_HEIGHT,height)
cam.set(cv2.CAP_PROP_FPS, 30)
cam.set(cv2.CAP_PROP_FOURCC,cv2.VideoWriter_fourcc(*'MJPG'))
while True:
    ignore,  frame = cam.read()
    frame[140:220,250:390]=(255,0,0)
    cv2.rectangle(frame,upperLeft,lowerRight,(0,255,0),lineW)
    cv2.circle(frame,(int(width/2),int(height/2)),myRadius,myColor,myThick)
    cv2.putText(frame,myText,(120,60),myFont,fontH,(0,0,255),fontT)
    cv2.imshow('my WEBcam', frame)
    cv2.moveWindow('my WEBcam',0,0)
    if cv2.waitKey(1) & 0xff ==ord('q'):
        break
cam.release()

import cv2

print(cv2.__version__)

width=640

height=360

myRadius=30

myColor=(0,0,0)

myThick=2

fontH=2

fontT=2

myText='Paul is Boss'

myFont=cv2.FONT_HERSHEY_DUPLEX

upperLeft=(250,140)

lowerRight=(390,220)

lineW=4

cam=cv2.VideoCapture(1,cv2.CAP_DSHOW)

cam.set(cv2.CAP_PROP_FRAME_WIDTH, width)

cam.set(cv2.CAP_PROP_FRAME_HEIGHT,height)

cam.set(cv2.CAP_PROP_FPS, 30)

cam.set(cv2.CAP_PROP_FOURCC,cv2.VideoWriter_fourcc(*'MJPG'))

while True:

ignore, frame = cam.read()

frame[140:220,250:390]=(255,0,0)

cv2.rectangle(frame,upperLeft,lowerRight,(0,255,0),lineW)

cv2.circle(frame,(int(width/2),int(height/2)),myRadius,myColor,myThick)

cv2.putText(frame,myText,(120,60),myFont,fontH,(0,0,255),fontT)

cv2.imshow('my WEBcam', frame)

cv2.moveWindow('my WEBcam',0,0)

if cv2.waitKey(1) & 0xff ==ord('q'):

break

cam.release()

Arduino, Tutorial

ARDUINO TUTORIAL 68: Make a Remote Controlled RGB LED with Brightness and Color Control

June 30, 2020 admin

In this lesson we take you through step-by-step instructions on creating a remotely controlled RGB LED. This is the solution to the Homework Assignment given in Tutorial 68. It is important for you to try and complete this on your own before looking at my solutions.

We are building this with parts from our Elegoo Kit , and our actual build is using an Arduino Nano, which allows the project to be built on a single breadboard. You can get the neat jumper wires HERE.

This video steps you through our build.

Below is the code we developed in this video.

#include <IRremote.h>
int IRpin=9;
IRrecv IR(IRpin);
decode_results cmd;
String myCom;

int rPin=6;
int gPin=10;
int bPin=5;

int rBright=255;
int gBright=255;
int bBright=255;

float dFact=1;


void setup()
{
Serial.begin(9600);
IR.enableIRIn();

pinMode(rPin,OUTPUT);
pinMode(gPin,OUTPUT);
pinMode(bPin,OUTPUT);

}

void loop() {
  while (IR.decode(&cmd)==0){ 
}
delay(1500);
IR.resume();

if (cmd.value==0xFF6897){
  myCom="zero";
  Serial.println(myCom); 
}
if (cmd.value==0xFF30CF){
  myCom="one";
  Serial.println(myCom); 
}
if (cmd.value==0xFF18E7){
  myCom="two";
  Serial.println(myCom); 
}
if (cmd.value==0xFF7A85){
  myCom="three";
  Serial.println(myCom); 
}
if (cmd.value==0xFF10EF){
  myCom="four";
  Serial.println(myCom); 
}
if (cmd.value==0xFF38C7){
  myCom="five";
  Serial.println(myCom); 
}
if (cmd.value==0xFF5AA5){
  myCom="six";
  Serial.println(myCom); 
}
if (cmd.value==0xFF42BD){
  myCom="seven";
  Serial.println(myCom); 
}
if (cmd.value==0xFF4AB5){
  myCom="eight";
  Serial.println(myCom); 
}
if (cmd.value==0xFF52AD){
  myCom="nine";
  Serial.println(myCom); 
}

if (cmd.value==0xFFA25D){
  myCom="pwr";
  Serial.println(myCom); 
}
if (cmd.value==0xFF629D){
  myCom="v+";
  Serial.println(myCom);
}
if (cmd.value==0xFFE21D){
  myCom="fun";
  Serial.println(myCom);
}
if (cmd.value==0xFF22DD){
  myCom="rew";
  Serial.println(myCom);
}
if (cmd.value==0xFF02FD){
  myCom="play";
  Serial.println(myCom);
}
if (cmd.value==0xFFC23D){
  myCom="ff";
  Serial.println(myCom);
}
if (cmd.value==0xFFE01F){
  myCom="dn";
  Serial.println(myCom);
}
if (cmd.value==0xFFA857){
  myCom="v-";
  Serial.println(myCom);
}
if (cmd.value==0xFF906F){
  myCom="up";
  Serial.println(myCom);
}
if (cmd.value==0xFF9867){
  myCom="eq";
  Serial.println(myCom);
}
if (cmd.value==0xFFB04F
){
  myCom="st";
  Serial.println(myCom);
}
if(myCom=="pwr"){
  rBright=255;
  gBright=255;
  bBright=255;
  dFact=1;
}

if(myCom=="fun"){
  rBright=0;
  gBright=0;
  bBright=0;
  dFact=0;
}
if(myCom=="zero"){
  rBright=255;
  gBright=255;
  bBright=255;
}
if(myCom=="one"){
  rBright=255;
  gBright=0;
  bBright=0;
}
if(myCom=="two"){
  rBright=0;
  gBright=255;
  bBright=0;
}
if(myCom=="three"){
  rBright=0;
  gBright=0;
  bBright=255;
}
if(myCom=="four"){
  rBright=0;
  gBright=255;
  bBright=255;
}
if(myCom=="five"){
  rBright=255;
  gBright=0;
  bBright=150;
}
if(myCom=="six"){
  rBright=255;
  gBright=255;
  bBright=0;
}
if (myCom=="dn"){
  dFact=dFact*.75;
}
if (myCom=="up"){
  dFact=dFact*1.3;
  if (dFact>1){
    dFact=1;
  }
}

analogWrite(rPin,rBright*dFact);
analogWrite(gPin,gBright*dFact);
analogWrite(bPin,bBright*dFact);
}

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#include <IRremote.h>

int IRpin=9;

IRrecv IR(IRpin);

decode_results cmd;

String myCom;

int rPin=6;

int gPin=10;

int bPin=5;

int rBright=255;

int gBright=255;

int bBright=255;

float dFact=1;

void setup()

{

Serial.begin(9600);

IR.enableIRIn();

pinMode(rPin,OUTPUT);

pinMode(gPin,OUTPUT);

pinMode(bPin,OUTPUT);

}

void loop() {

while (IR.decode(&cmd)==0){

}

delay(1500);

IR.resume();

if (cmd.value==0xFF6897){

myCom="zero";

Serial.println(myCom);

}

if (cmd.value==0xFF30CF){

myCom="one";

Serial.println(myCom);

}

if (cmd.value==0xFF18E7){

myCom="two";

Serial.println(myCom);

}

if (cmd.value==0xFF7A85){

myCom="three";

Serial.println(myCom);

}

if (cmd.value==0xFF10EF){

myCom="four";

Serial.println(myCom);

}

if (cmd.value==0xFF38C7){

myCom="five";

Serial.println(myCom);

}

if (cmd.value==0xFF5AA5){

myCom="six";

Serial.println(myCom);

}

if (cmd.value==0xFF42BD){

myCom="seven";

Serial.println(myCom);

}

if (cmd.value==0xFF4AB5){

myCom="eight";

Serial.println(myCom);

}

if (cmd.value==0xFF52AD){

myCom="nine";

Serial.println(myCom);

}

if (cmd.value==0xFFA25D){

myCom="pwr";

Serial.println(myCom);

}

if (cmd.value==0xFF629D){

myCom="v+";

Serial.println(myCom);

}

if (cmd.value==0xFFE21D){

myCom="fun";

Serial.println(myCom);

}

if (cmd.value==0xFF22DD){

myCom="rew";

Serial.println(myCom);

}

if (cmd.value==0xFF02FD){

myCom="play";

Serial.println(myCom);

}

if (cmd.value==0xFFC23D){

myCom="ff";

Serial.println(myCom);

}

if (cmd.value==0xFFE01F){

myCom="dn";

Serial.println(myCom);

}

if (cmd.value==0xFFA857){

myCom="v-";

Serial.println(myCom);

}

if (cmd.value==0xFF906F){

myCom="up";

Serial.println(myCom);

}

if (cmd.value==0xFF9867){

myCom="eq";

Serial.println(myCom);

}

if (cmd.value==0xFFB04F

){

myCom="st";

Serial.println(myCom);

}

if(myCom=="pwr"){

rBright=255;

gBright=255;

bBright=255;

dFact=1;

}

if(myCom=="fun"){

rBright=0;

gBright=0;

bBright=0;

dFact=0;

}

if(myCom=="zero"){

rBright=255;

gBright=255;

bBright=255;

}

if(myCom=="one"){

rBright=255;

gBright=0;

bBright=0;

}

if(myCom=="two"){

rBright=0;

gBright=255;

bBright=0;

}

if(myCom=="three"){

rBright=0;

gBright=0;

bBright=255;

}

if(myCom=="four"){

rBright=0;

gBright=255;

bBright=255;

}

if(myCom=="five"){

rBright=255;

gBright=0;

bBright=150;

}

if(myCom=="six"){

rBright=255;

gBright=255;

bBright=0;

}

if (myCom=="dn"){

dFact=dFact*.75;

}

if (myCom=="up"){

dFact=dFact*1.3;

if (dFact>1){

dFact=1;

}

analogWrite(rPin,rBright*dFact);

analogWrite(gPin,gBright*dFact);

analogWrite(bPin,bBright*dFact);

}

Arduino, Tutorial

ARDUINO TUTORIAL 67: Create a Remote Controlled RGB LED with Brightness and Color Control

June 23, 2020 admin

In this video we give you a homework assignment to create a dimmable RGB LED. You must set color and brightness using the IR remote. In Tutorial 68 we will take you through the build, and show you the solution. I hope you will really try your best to do it on your own before you check out my solution.

Technology Tutorials

Category Archives: Tutorial

Raspberry Pi LESSON 37: Raspberry Pi Security System

Improved Gesture Recognition in Python and MediaPipe

Putting Text, Rectangles and Circles on Images in OpenCV for Windows

ARDUINO TUTORIAL 68: Make a Remote Controlled RGB LED with Brightness and Color Control

ARDUINO TUTORIAL 67: Create a Remote Controlled RGB LED with Brightness and Color Control

Making The World a Better Place One High Tech Project at a Time. Enjoy!