RpiVersion.py

#!/usr/bin/env python3
import numpy as np
import cv2
import pyocr
import pyocr.builders
from PIL import Image
import re
from firebase import firebase
import datetime
import RPi.GPIO as GPIO
import time

#GPIO
GPIO.setmode(GPIO.BCM)
GPIO.setup(23, GPIO.IN, pull_up_down=GPIO.PUD_UP)#Button to GPIO23
GPIO.setup(24, GPIO.OUT)  #LED to GPIO24
print("[INFO]:GPIO Set")

# Lists serve as the file
nameList = []
regNoList = []

# Firebase path
firebase = firebase.FirebaseApplication('https://vision-based-id-reader.firebaseio.com/', None)
print("[INFO]:Firebase Initialized")

#Regex for Registration Number
def extract_reg_number(string):
    pat3 = re.compile(r'[0-2][0-9][B|M][A-Z][A-Z][0-2][0-9][0-9][0-9]')
    re3 = pat3.findall(string)
    re3 = ''.join(re3)
    return re3

#Regex for Name
def extract_names(string):
    pattern = re.compile(r'[A-Z][a-z]+')
    names = pattern.findall(string)
    newname = ' '.join(names)
    return newname

# Activate Tesseract
tools = pyocr.get_available_tools()
tool = tools[0]
print("[INFO]:Tesseract Activated")

# Open Camera
cap = cv2.VideoCapture(0)
print("[INFO]:Camera On")
try:
	while(True):
		button_state = GPIO.input(23)
		
		#Image Preprocessing
		ret, frame = cap.read()
		frame = cv2.flip(frame, -1)
		gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
		
		#OCR in Action
		txt = tool.image_to_string(Image.fromarray(gray), builder=pyocr.builders.TextBuilder())
		print(txt)
		RegID = extract_reg_number(txt)
		Name = extract_names(txt)
		
		if(RegID != ""):
			regNoList.append(RegID)
		
		if(Name != ""):
			nameList.append(Name)
			
		if button_state==False:	
			GPIO.output(24, 1)
			print('[INFO]:Button pressed')
			time.sleep(0.2)
			GPIO.output(24,0)
			break
		else:
			GPIO.output(24, 0)
except:
	GPIO.cleanup()	
# When everything done, release the capture
cap.release()
cv2.destroyAllWindows()

# Get the frequency of elements and the elements as lists (in ascending order)
regfreq = np.unique(regNoList, return_counts=True)[1].tolist()
regval = np.unique(regNoList, return_counts=True)[0].tolist()

namefreq = np.unique(nameList, return_counts=True)[1].tolist()
nameval = np.unique(nameList, return_counts=True)[0].tolist()

#Failsafe
if regNoList == [] and nameList == [] or regfreq==[] and namefreq==[]:
    print("[ERR]:No ID Card Detected")

#Get the index where the maximum value is located
else:
	maxNameIndex = regfreq.index(max(regfreq))
	maxRegIndex = namefreq.index(max(namefreq))
	Time = datetime.datetime.now()

    # Store Name and Reg Number
	ID = regval[maxNameIndex]
	Name = nameval[maxRegIndex]
	Time = Time.strftime("%H:%M:%S %d-%m-%Y")

    #Pushing to Firebase
	Creds = {"Time":Time,"Registration Number": ID, "Name": Name}
	print("Name:", Name)
	print("Registration Number:", ID)
	print("[INFO]:If details are correct, hold the button")

	#Confirming the Details
	button_state = GPIO.input(23)
	for i in range(0,4):
		time.sleep(1)
	
	time.sleep(2)	
	if button_state==False:
		GPIO.output(24, 1)
		print('[INFO]:Posting to Firebase')
		results = firebase.post("/Testdata/", Creds)
		print("[INFO]:Your details have been registered")
		time.sleep(0.2)
		GPIO.output(24,0)
	else: 
		print("[ERR]:Details are incorrectly read,Please try again")
		
	GPIO.cleanup()