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()

3D Graphics with Visual Python

Python 3D Graphics Tutorial 5: Bouncing Ball Simulation in Visual Python

August 21, 2021 admin

The program below is the code we developed in Lesson 5. It is a Vpython program that creates a 3D model of a marble bouncing in a box.

from vpython import *
from time import *
mRadius=.5
wallThickness=.1
roomWidth=12
roomDepth=20
roomHeight=2
floor=box(pos=vector(0,-roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)
ceiling=box(pos=vector(0,roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)
backWall=box(pos=vector(0,0,-roomDepth/2),size=vector(roomWidth,roomHeight,wallThickness), color=color.white)
leftWall=box(pos=vector(-roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)
rightWall=box(pos=vector(roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)
marble=sphere(radius=mRadius,color=color.red)
deltaX=.1
deltaY=.1
deltaZ=.1

xPos=0
yPos=0
zPos=0

while True:
    rate(25)

    xPos=xPos+deltaX
    yPos=yPos+deltaY
    zPos=zPos+deltaZ

    Xrme=xPos+mRadius
    Xlme=xPos-mRadius
    Ytme=yPos+mRadius
    Ybme=yPos-mRadius
    Zbme=zPos-mRadius
    Zfme=zPos+mRadius

    Rwe=roomWidth/2-wallThickness/2
    Lwe=-roomWidth/2+wallThickness/2
    Cwe=roomHeight/2-wallThickness/2
    FLOORwe=-roomHeight/2+wallThickness/2
    Bwe=-roomDepth/2+wallThickness/2
    Fwe=roomDepth/2-wallThickness/2

    if (Xrme>=Rwe or Xlme<=Lwe):
        deltaX=deltaX*(-1)

    if (Ytme>=Cwe or Ybme<=FLOORwe):
        deltaY=deltaY*(-1)

    if (Zfme>=Fwe or Zbme<=Bwe):
        deltaZ=deltaZ*(-1)

    marble.pos=vector(xPos,yPos,zPos)

from vpython import *

from time import *

mRadius=.5

wallThickness=.1

roomWidth=12

roomDepth=20

roomHeight=2

floor=box(pos=vector(0,-roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)

ceiling=box(pos=vector(0,roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)

backWall=box(pos=vector(0,0,-roomDepth/2),size=vector(roomWidth,roomHeight,wallThickness), color=color.white)

leftWall=box(pos=vector(-roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)

rightWall=box(pos=vector(roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)

marble=sphere(radius=mRadius,color=color.red)

deltaX=.1

deltaY=.1

deltaZ=.1

xPos=0

yPos=0

zPos=0

while True:

rate(25)

xPos=xPos+deltaX

yPos=yPos+deltaY

zPos=zPos+deltaZ

Xrme=xPos+mRadius

Xlme=xPos-mRadius

Ytme=yPos+mRadius

Ybme=yPos-mRadius

Zbme=zPos-mRadius

Zfme=zPos+mRadius

Rwe=roomWidth/2-wallThickness/2

Lwe=-roomWidth/2+wallThickness/2

Cwe=roomHeight/2-wallThickness/2

FLOORwe=-roomHeight/2+wallThickness/2

Bwe=-roomDepth/2+wallThickness/2

Fwe=roomDepth/2-wallThickness/2

if (Xrme>=Rwe or Xlme<=Lwe):

deltaX=deltaX*(-1)

if (Ytme>=Cwe or Ybme<=FLOORwe):

deltaY=deltaY*(-1)

if (Zfme>=Fwe or Zbme<=Bwe):

deltaZ=deltaZ*(-1)

marble.pos=vector(xPos,yPos,zPos)

3D Graphics with Visual Python

Python 3D Graphics LESSON 4: Understanding 3D Motion in Visual Python Model

August 14, 2021 admin

In this lesson we show how to make an animated ball properly bounce off a wall using Visual Python (Vpython).

from vpython import *
from time import *
mRadius=2
wallThickness=1
roomWidth=15
roomDepth=12
roomHeight=8
floor=box(pos=vector(0,-roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)
ceiling=box(pos=vector(0,roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)
backWall=box(pos=vector(0,0,-roomDepth/2),size=vector(roomWidth,roomHeight,wallThickness), color=color.white)
leftWall=box(pos=vector(-roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)
rightWall=box(pos=vector(roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)
marble=sphere(radius=mRadius,color=color.red)
deltaX=.1
xPos=0
while True:
    rate(25)
    xPos=xPos+deltaX
    Xrme=xPos+mRadius
    Xlme=xPos-mRadius
    Rwe=roomWidth/2-wallThickness/2
    Lwe=-roomWidth/2+wallThickness/2
    if (Xrme>=Rwe or Xlme<Lwe):
        deltaX=deltaX*(-1)
    marble.pos=vector(xPos,0,0)

from vpython import *

from time import *

mRadius=2

wallThickness=1

roomWidth=15

roomDepth=12

roomHeight=8

floor=box(pos=vector(0,-roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)

ceiling=box(pos=vector(0,roomHeight/2,0),size=vector(roomWidth,wallThickness,roomDepth), color=color.white)

backWall=box(pos=vector(0,0,-roomDepth/2),size=vector(roomWidth,roomHeight,wallThickness), color=color.white)

leftWall=box(pos=vector(-roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)

rightWall=box(pos=vector(roomWidth/2,0,0),size=vector(wallThickness,roomHeight,roomDepth), color=color.white)

marble=sphere(radius=mRadius,color=color.red)

deltaX=.1

xPos=0

while True:

rate(25)

xPos=xPos+deltaX

Xrme=xPos+mRadius

Xlme=xPos-mRadius

Rwe=roomWidth/2-wallThickness/2

Lwe=-roomWidth/2+wallThickness/2

if (Xrme>=Rwe or Xlme<Lwe):

deltaX=deltaX*(-1)

marble.pos=vector(xPos,0,0)

Python

Faster Launch of WEBcam and Smoother Video in OpenCV on Windows

August 12, 2021 admin

This is the code we developed in Video Lesson #6 showing how to launch a webcam quicker and with less delay in OpenCV running on windows. The video above explains the code step by step, but for your convenience, I include the code below.

import cv2
print(cv2.__version__)
width=1280
height=720
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()
    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=1280

height=720

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()

cv2.imshow('my WEBcam', frame)

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

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

break

cam.release()

OpenCV, Python

Controlling a WEBcam in OpenCV on Windows

August 5, 2021 admin

In this lesson we show how to move a frame in OpenCV, how to convert a color image to grayscale, and then how to display multiple video windows. For your convenience, I include the code below that we develop in this video.

import cv2
print(cv2.__version__)
cam=cv2.VideoCapture(1)
while True:
    ignore,  frame = cam.read()
    gray=cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)
    cv2.imshow('my WEBcam', frame)
    cv2.moveWindow('my WEBcam',0,0)
    cv2.imshow('my grayFrame', gray)
    cv2.moveWindow('my grayFrame',640,0)

    cv2.imshow('my WEBcam2', frame)
    cv2.moveWindow('my WEBcam2',640,480)
    cv2.imshow('my grayFrame2', gray)
    cv2.moveWindow('my grayFrame2',0,480)
    

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

import cv2

print(cv2.__version__)

cam=cv2.VideoCapture(1)

while True:

ignore, frame = cam.read()

gray=cv2.cvtColor(frame,cv2.COLOR_BGR2GRAY)

cv2.imshow('my WEBcam', frame)

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

cv2.imshow('my grayFrame', gray)

cv2.moveWindow('my grayFrame',640,0)

cv2.imshow('my WEBcam2', frame)

cv2.moveWindow('my WEBcam2',640,480)

cv2.imshow('my grayFrame2', gray)

cv2.moveWindow('my grayFrame2',0,480)

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

break

cam.release()

Technology Tutorials

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

Python 3D Graphics Tutorial 5: Bouncing Ball Simulation in Visual Python

Python 3D Graphics LESSON 4: Understanding 3D Motion in Visual Python Model

Faster Launch of WEBcam and Smoother Video in OpenCV on Windows

Controlling a WEBcam in OpenCV on Windows

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

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

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