AI on the Edge LESSON 28: Use Pan Tilt Camera to Track Object of Interest in OpenCV

In this video lesson we learn how to track our object of interest using the Pan Tilt camera. The camera will constantly adjust position to keep the Object of Interest in the center of the camera frame. We identify the Object of Interest based on Color, as we learned in earlier lessons. In this video, we developed the code below:

import cv2
import time
from picamera2 import Picamera2
from fusion_hat.pwm import PWM
from fusion_hat.servo import Servo
panPin = 2
tiltPin = 3
panServo = Servo(panPin)
tiltServo = Servo(tiltPin)
panAngle = 0
tiltAngle = 0
panServo.angle(panAngle)
tiltServo.angle(tiltAngle)

piCam = Picamera2()
W=1280
H=720
tStart = time.time()
fps = 0

xFrameC = int((W-1)/2)
yFrameC = int((H-1)/2)
xBoxC = xFrameC
yBoxC = yFrameC


redPin = 5
greenPin = 6
bluePin = 7
redLED = PWM(redPin)
greenLED = PWM(greenPin)
blueLED = PWM(bluePin)

RES = (W,H)
piCam.preview_configuration.main.size = RES
piCam.preview_configuration.main.format = "RGB888"
piCam.preview_configuration.controls.FrameRate=60
piCam.preview_configuration.align()
piCam.configure("preview")
piCam.start()

textLowerLeft = (int(W*.01),int(H*.06))
fontFace = cv2.FONT_HERSHEY_SIMPLEX
fontThickness = int(W/425)
fontScale = H*.0015
fontColor = (0,0,255)
xPos = 0
textLowerLeft1 = (int(W*.01),int(H*.06)*2)
textLowerLeft2 = (int(W*.01),int(H*.06)*3)
yPos = 0
valR = 0
valG = 0
valB = 0

Hue = 0
Sat = 0
Val = 0

LC = (25,100,90)
UC = (35,255,255)

frame = None
def mouseAction(event, x, y, flags, param):
    global frame, xPos, yPos, Hue, Sat, Val
    if event == 0:
        xPos = x
        yPos = y
        if frame is not None:
            valB, valG, valR = frame[y,x]
            redLED.pulse_width_percent(int(valR/255*100))
            greenLED.pulse_width_percent(int(valG/255*100/2))
            blueLED.pulse_width_percent(int(valB/255*100/4))
            frameHSV = cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)
            Hue, Sat, Val =frameHSV[y,x]
cv2.namedWindow('Camera',cv2.WINDOW_GUI_NORMAL)
cv2.moveWindow('Camera',0,65)
cv2.resizeWindow('Camera',W,H)

cv2.namedWindow('Mask',cv2.WINDOW_GUI_NORMAL)
cv2.moveWindow('Mask',W,65)
cv2.resizeWindow('Mask',int(W/2),int(H/2))

cv2.namedWindow('Composite',cv2.WINDOW_GUI_NORMAL)
cv2.moveWindow('Composite',W,65+int(H/2)+25)
cv2.resizeWindow('Composite',int(W/2),int(H/2))

cv2.setMouseCallback('Camera',mouseAction)

while True:
    deltaT = time.time() - tStart
    tStart=time.time()
    fps = fps*.95 + (1/deltaT)*.05
    frame= piCam.capture_array()
    frame=cv2.flip(frame,-1)
    
    frameHSV = cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)
    mask=cv2.inRange(frameHSV,LC,UC)
    composite = cv2.bitwise_and(frame, frame, mask=mask)
    
    contours, _ =cv2.findContours(mask,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)
    if contours:
        #cv2.drawContours(frame,contours,-1,(255,0,0),3)
        largestContour = max(contours, key = cv2.contourArea)
        area = cv2.contourArea(largestContour)
        if area>100:
            #cv2.drawContours(frame,largestContour,-1,(255,0,0),3)
            x, y, w, h = cv2.boundingRect(largestContour)
            cv2.rectangle(frame, (x,y),(x+w,y+h),(0,255,0),3)
            xBoxC  =  x + int(w/2)
            yBoxC  =  y + int(h/2)
            
            xError = xBoxC - xFrameC
            yError = yBoxC - yFrameC
            
            cv2.circle(frame,(xFrameC,yFrameC),10,(255,0,0),-1)
            cv2.circle(frame,(xBoxC,yBoxC), 40,(0,0,255),3)
            if abs(xError) >40:
                if xError >0:
                    panAngle = panAngle -1
                    panServo.angle(panAngle)
                    time.sleep(.02)
                if xError <0:
                    panAngle = panAngle + 1
                    panServo.angle(panAngle)
                    time.sleep(.02)
            if abs(yError) >40:
                if yError >0:
                    tiltAngle = tiltAngle +1
                    tiltServo.angle(tiltAngle)
                    time.sleep(.02)
                if yError <0:
                    tiltAngle = tiltAngle - 1
                    tiltServo.angle(tiltAngle)
                    time.sleep(.02)
            
    myText = "FPS: "+str(round(fps,1))
    cv2.putText(frame,myText,textLowerLeft,fontFace,fontScale,fontColor,fontThickness)
    
    text1 = "Mouse Pos: "+str((xPos,yPos))
    text2 = "Pixel Color: "+str((Hue,Sat,Val))
    cv2.putText(frame,text1,textLowerLeft1,fontFace,fontScale,fontColor,fontThickness)    
    cv2.putText(frame,text2,textLowerLeft2,fontFace,fontScale,fontColor,fontThickness)    
    cv2.imshow("Camera", frame)
    cv2.imshow("Composite",composite)
    cv2.imshow("Mask",mask)

    if cv2.waitKey(1)==ord('q'):
        break
cv2.destroyAllWindows()
redLED.pulse_width_percent(0)
greenLED.pulse_width_percent(0)
blueLED.pulse_width_percent(0)
print('Program Terminated')

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import cv2

import time

from picamera2 import Picamera2

from fusion_hat.pwm import PWM

from fusion_hat.servo import Servo

panPin = 2

tiltPin = 3

panServo = Servo(panPin)

tiltServo = Servo(tiltPin)

panAngle = 0

tiltAngle = 0

panServo.angle(panAngle)

tiltServo.angle(tiltAngle)

piCam = Picamera2()

W=1280

H=720

tStart = time.time()

fps = 0

xFrameC = int((W-1)/2)

yFrameC = int((H-1)/2)

xBoxC = xFrameC

yBoxC = yFrameC

redPin = 5

greenPin = 6

bluePin = 7

redLED = PWM(redPin)

greenLED = PWM(greenPin)

blueLED = PWM(bluePin)

RES = (W,H)

piCam.preview_configuration.main.size = RES

piCam.preview_configuration.main.format = "RGB888"

piCam.preview_configuration.controls.FrameRate=60

piCam.preview_configuration.align()

piCam.configure("preview")

piCam.start()

textLowerLeft = (int(W*.01),int(H*.06))

fontFace = cv2.FONT_HERSHEY_SIMPLEX

fontThickness = int(W/425)

fontScale = H*.0015

fontColor = (0,0,255)

xPos = 0

textLowerLeft1 = (int(W*.01),int(H*.06)*2)

textLowerLeft2 = (int(W*.01),int(H*.06)*3)

yPos = 0

valR = 0

valG = 0

valB = 0

Hue = 0

Sat = 0

Val = 0

LC = (25,100,90)

UC = (35,255,255)

frame = None

def mouseAction(event, x, y, flags, param):

global frame, xPos, yPos, Hue, Sat, Val

if event == 0:

xPos = x

yPos = y

if frame is not None:

valB, valG, valR = frame[y,x]

redLED.pulse_width_percent(int(valR/255*100))

greenLED.pulse_width_percent(int(valG/255*100/2))

blueLED.pulse_width_percent(int(valB/255*100/4))

frameHSV = cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)

Hue, Sat, Val =frameHSV[y,x]

cv2.namedWindow('Camera',cv2.WINDOW_GUI_NORMAL)

cv2.moveWindow('Camera',0,65)

cv2.resizeWindow('Camera',W,H)

cv2.namedWindow('Mask',cv2.WINDOW_GUI_NORMAL)

cv2.moveWindow('Mask',W,65)

cv2.resizeWindow('Mask',int(W/2),int(H/2))

cv2.namedWindow('Composite',cv2.WINDOW_GUI_NORMAL)

cv2.moveWindow('Composite',W,65+int(H/2)+25)

cv2.resizeWindow('Composite',int(W/2),int(H/2))

cv2.setMouseCallback('Camera',mouseAction)

while True:

deltaT = time.time() - tStart

tStart=time.time()

fps = fps*.95 + (1/deltaT)*.05

frame= piCam.capture_array()

frame=cv2.flip(frame,-1)

frameHSV = cv2.cvtColor(frame,cv2.COLOR_BGR2HSV)

mask=cv2.inRange(frameHSV,LC,UC)

composite = cv2.bitwise_and(frame, frame, mask=mask)

contours, _ =cv2.findContours(mask,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_SIMPLE)

if contours:

#cv2.drawContours(frame,contours,-1,(255,0,0),3)

largestContour = max(contours, key = cv2.contourArea)

area = cv2.contourArea(largestContour)

if area>100:

#cv2.drawContours(frame,largestContour,-1,(255,0,0),3)

x, y, w, h = cv2.boundingRect(largestContour)

cv2.rectangle(frame, (x,y),(x+w,y+h),(0,255,0),3)

xBoxC = x + int(w/2)

yBoxC = y + int(h/2)

xError = xBoxC - xFrameC

yError = yBoxC - yFrameC

cv2.circle(frame,(xFrameC,yFrameC),10,(255,0,0),-1)

cv2.circle(frame,(xBoxC,yBoxC), 40,(0,0,255),3)

if abs(xError) >40:

if xError >0:

panAngle = panAngle -1

panServo.angle(panAngle)

time.sleep(.02)

if xError <0:

panAngle = panAngle + 1

panServo.angle(panAngle)

time.sleep(.02)

if abs(yError) >40:

if yError >0:

tiltAngle = tiltAngle +1

tiltServo.angle(tiltAngle)

time.sleep(.02)

if yError <0:

tiltAngle = tiltAngle - 1

tiltServo.angle(tiltAngle)

time.sleep(.02)

myText = "FPS: "+str(round(fps,1))

cv2.putText(frame,myText,textLowerLeft,fontFace,fontScale,fontColor,fontThickness)

text1 = "Mouse Pos: "+str((xPos,yPos))

text2 = "Pixel Color: "+str((Hue,Sat,Val))

cv2.putText(frame,text1,textLowerLeft1,fontFace,fontScale,fontColor,fontThickness)

cv2.putText(frame,text2,textLowerLeft2,fontFace,fontScale,fontColor,fontThickness)

cv2.imshow("Camera", frame)

cv2.imshow("Composite",composite)

cv2.imshow("Mask",mask)

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

break

cv2.destroyAllWindows()

redLED.pulse_width_percent(0)

greenLED.pulse_width_percent(0)

blueLED.pulse_width_percent(0)

print('Program Terminated')

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AI on the Edge LESSON 28: Use Pan Tilt Camera to Track Object of Interest in OpenCV

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