img.show() not displaying image window

Question

I am new to this but I am writing a program to first create and encrypt passwords, then encode the encrypted passwords into downloaded images then finally, insert the encoded images to a database.

Here's my code;

import os
import re
import urllib.request
import mysql.connector
from Password import *
import image
import stepic
from PIL import Image

targetFileDir='MTUFacultyImages'
isExist = os.path.exists(targetFileDir)
if not isExist:  
    # Create a new directory because it does not exist 
    os.makedirs(targetFileDir)

def convertImageToBinaryData(filename):
    # Convert digital data to binary format
    with open(filename, 'rb') as file:
        binaryData = file.read()
    return binaryData

def writeBinaryDataToImage(data, filename):
    # Convert binary data to proper format and write it on Hard Disk
    with open(filename, 'wb') as file:
        file.write(data)
    
# connect the db
db_connection = mysql.connector.connect( 
host= "localhost", 
user= "root", 
password= "password") 
#database="faculty_db" ) 
# creating database
db_cursor = db_connection.cursor()

faculty_list_info=[]

class faculty_record:
    def __init__(self,first_Name, last_Name, title, office, phone, e_mail, photo_file_name, photo_link ):
        self.First_Name=first_Name
        self.Last_Name=last_Name
        self.Title=title
        self.Office=office
        self.Phone=phone
        self.E_mail=e_mail
        self.PhotoFileName=photo_file_name
        self.PhotoLink=photo_link
    

def Faculty_record_extraction():
    req =urllib.request.Request('https://www.mtu.edu/computing/departments/applied-computing/faculty/',headers={'User-Agent': 'Mozilla/5.0'})
    page = urllib.request.urlopen(req)  
    #read the string 
    str=page.read().decode('utf-8')
    print(str)
    #construct pattern to search
    pattern_str=("<img.+src=\"([\S./-]+/([\S.-]+.jpg))\".+/>\s+</a>\s+</div>\s+<div\s+class=\"person_bio\">\s+<div\s+class=\"personal\">\s+"
                 "<h2>\s*<a\s+href=\"[\S\.-/]+\">([\D]+)\s+([\D]+)</a></h2>\s*"
                 "<ul\s+class=\"none\">\s*<li>([A-Za-z,\s]+)</li>\s*<li>.+</li>\s*</ul>\s*</div>\s*"
                      "<div\s+class=\"left\">\s*<div\s+class=\"contact\">\s*<ul\s+class=\"none\">"
                      "\s*<li\s+class=\"email-address\">\s*<a\s+href=\"\S+\">(\S+)</a>\s*</li>\s*<li\s+class=\"phone-number\">\s*<a\s+href=\"\S+\">([\S-]+)</a>\s*</li>\s*"
                      "<li\s+class=\"place\">([\w\s]+)</li>\s*</ul>\s*</div>")

    global faculty_list_info
    faculty_list_search=re.findall(pattern_str,str)
    # download images
    image_url_prefix='https://www.mtu.edu'  
    opener = urllib.request.URLopener()   ## read https://stackoverflow.com/questions/34957748/http-error-403-forbidden-with-urlretrieve
    opener.addheader('User-Agent', 'Mozilla/5.0')
    for each_faculty in faculty_list_search:       
        #print("First Name: ", each_faculty[2],"Last Name",each_faculty[3])
        print(image_url_prefix+each_faculty[0])
        opener.retrieve(image_url_prefix+each_faculty[0],targetFileDir+"/"+each_faculty[1]) # download and save images
        #download_file(image_url_prefix+each_faculty[0],targetFileDir+"/"+each_faculty[1])
        faculty_list_info.append(faculty_record(each_faculty[2],each_faculty[3],each_faculty[4],each_faculty[7],each_faculty[6],each_faculty[5],each_faculty[1],image_url_prefix+each_faculty[0])) # save faculty info

def Faculty_record_Store():
    global db_cursor

    # if faculty_db exists, drop/ remove it
    db_cursor.execute("SHOW DATABASES LIKE 'faculty_db'")
    for db in db_cursor: 
       print(db)
    if db_cursor.rowcount>0:
        print('faculty_db found, I will drop it now')
        db_cursor.execute("DROP DATABASE faculty_db")

    # executing cursor with execute method and pass SQL query
    db_cursor.execute("CREATE DATABASE faculty_db") 

    # get list of all databases 
    db_cursor.execute("SHOW DATABASES") 

    #print all databases 
    for db in db_cursor: 
           print(db)
    db_cursor.execute("USE faculty_db")

    # creating the table 
    db_cursor.execute("CREATE TABLE faculty("
    "first_Name varchar(20), last_Name varchar(20),title varchar(60), office varchar(20),phone varchar(20),e_mail varchar(20),photo_file_name varchar(128),photo_link varchar(512),photo LONGBLOB NOT NULL,"
    "CONSTRAINT PK_FACULTY PRIMARY KEY (first_Name,last_Name))")

    #Get database table 
    db_cursor.execute("SHOW TABLES") 
    for table in db_cursor: 
         print(table)

    # store faculty records to the db
    global faculty_list_info
    add_records = "INSERT INTO faculty(first_Name,last_Name,title,office,phone,e_mail,photo_file_name,photo_link,photo) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s)"
    records_vals= []
    for each_faculty in faculty_list_info:
        each_faculty_photo = convertImageToBinaryData(targetFileDir+"/"+each_faculty.PhotoFileName)
        records_vals.append((each_faculty.First_Name,each_faculty.Last_Name,each_faculty.Title,each_faculty.Office,each_faculty.Phone,each_faculty.E_mail, each_faculty.PhotoFileName, each_faculty.PhotoLink,each_faculty_photo))
    print("********************************************************")   
    print(records_vals)

    #insert records to the database  
    db_cursor.executemany(add_records,records_vals) 
    db_connection.commit() 
    print(db_cursor.rowcount, "Record Inserted")

    # show records
    db_cursor.execute("SELECT * FROM faculty WHERE e_mail='whzhou@mtu.edu'")
    myresult = db_cursor.fetchall()
    for query_record in myresult:
        #print(x)
        writeBinaryDataToImage(query_record[8],query_record[0]+query_record[1]+".jpg")
    
# extract the information from the website
Faculty_record_extraction()
Faculty_record_Store()

#Using createPassword(8) and simple_encryption() to create and encrypt password for each faculty member 
faculty_password = []
for each_faculty in faculty_list_info:
    passwd = createPassword(8)
    print("Password : ", passwd)
    encrypted_text = simple_encryption(passwd,12)
    print("Cipher: ",encrypted_text)    
    faculty_password.append(encrypted_text)

# using information_hiding to encode each photo with hidden password 
def information_hiding(imagefile,text):
    for each_faculty_photo in each_faculty:
        imagefile = each_faculty_photo
        text = faculty_password

    print(information_hiding(each_faculty_photo, faculty_password))

# #to insert the photos with hidden pword into the table faculty
    image_vals =[]
    for x in faculty_password:
        img = Image.open(each_faculty_photo)
        img.show()
        img_encoded = stepic.encode(img, text)
        img_encoded.show()
        img_encoded.save(('hidden' + each_faculty_photo + '.PNG'), 'PNG')
        img_encoded.show()

    add_images = "INSERT INTO faculty (imagefile LONGBLOB NOT NULL) VALUES (%s)"
    for y in img_encoded:
        db_cursor.executemany(add_images,image_vals) 
        db_connection.commit() 
        print(db_cursor.rowcount, "Record Inserted")

I am not getting any errors, the passwords have been created and encrypted but the images are not being encoded and displaying and cannot figure out why.

Answer 1

Your question has a very simple answer:

The reason why the images don't show up is because you don't call anywhere in your code the information_hinding() function.

In other words the function which should show the images does not run at all if the code you have provided will be executed. This is also the reason why you are not getting any errors in spite of the fact that the function if actually run will fail raising an Error.

As an add-on to the answer some more about the code you have provided:

Let's take a look at the information_hinding() function to see that if you call it you will get an recursion Error because of recursive call of the function within itself without any condition of stopping the recursion:

# using information_hiding to encode each photo with hidden password 
def information_hiding(imagefile,text):
    for each_faculty_photo in each_faculty:
        imagefile = each_faculty_photo
        text = faculty_password
    # >>> RECURSIVE CALL: 
    print(information_hiding(each_faculty_photo, faculty_password))

I suggest also that you check what the for loop before the recursive call is expected to do because the only effect of it is to set imagefile to the last item in each_faculty and making text storing the entire faculty_password list.