Tkinter not displaying image right

Question

I'm making an image treatment program on Tkinter, and one of my function makes a Popart style image from the image the user selects. But the function takes quite some time, so I decided to add an image saying: "Image in treatment, please wait..." while the program is making the popart image. But it doesn't apply the modifications. It just starts the function as if it was skipping that part where I ask it to display that image. This is the problem function:

def usepop():
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\Requirements\\traitement.png") #The image "traitement.png" doesn't get displayed
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)
    pop_art(a, None, coef=4)
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\PopArt\\Result Image\\result.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)

And here is the full code:

from tkinter import*
import tkinter as Tkinter
from tkinter import filedialog, DISABLED, messagebox as tkMessageBox
import os
import ntpath
from PIL import Image, ImageTk, ImageFilter
import PIL
from collections import Counter
from random import randint
import random


def EchelleDeGris():
    Ima2=Image.new("RGB",(z[0],z[1]))
    px=Ima1.load()
    px1=Ima2.load()
    for x in range(z[0]):
        for y in range(z[1]):
            p=px[x,y]
            o=int((p[0]+p[1]+p[2])/3)
            px1[x,y]=(o,o,o)
    Ima2.save(""+dir_path+"ImageMod.png")
    im2 = ImageTk.PhotoImage(file=""+dir_path+"ImageMod.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)

def SupprimerImage():
    I2 = Tkinter.Label(main, image=imt)
    I2.grid(row=0, column=4, columnspan =4)

def Luminosite():
    Ima2=Image.new("RGB",(z[0],z[1]))
    px=Ima1.load()
    px1=Ima2.load()
    for x in range(z[0]):
        for y in range(z[1]):
            p=px[x,y]
            px1[x,y]=(p[0]+S1.get(),p[1]+S1.get(),p[2]+S1.get())
    Ima2.save(""+dir_path+"ImageMod.png")
    im2 = ImageTk.PhotoImage(file=""+dir_path+"ImageMod.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)

def AnnulerModifications():
    I2 = Tkinter.Label(main, image=im1)
    I2.grid(row=0, column=4, columnspan =4)

def get_pixel(pixels, x, y):
    try:
        return pixels[x, y]
    except IndexError:
        return None


def get_neighbors(pixels, x, y):
    neighbors = list()
    neighbors.append(get_pixel(pixels, x, y - 1))
    neighbors.append(get_pixel(pixels, x, y + 1))
    neighbors.append(get_pixel(pixels, x - 1, y))
    neighbors.append(get_pixel(pixels, x + 1, y))
    neighbors.append(get_pixel(pixels, x - 1, y - 1))
    neighbors.append(get_pixel(pixels, x - 1, y + 1))
    neighbors.append(get_pixel(pixels, x + 1, y - 1))
    neighbors.append(get_pixel(pixels, x + 1, y + 1))
    return neighbors


def filter_art(pixels, size):
    indexes = dict()
    for x in range(size[0]):
        for y in range(size[1]):
            color = get_pixel(pixels, x, y)
            neighbors = get_neighbors(pixels, x, y)
            new_color = Counter(neighbors).most_common()[0][0]
            if new_color is not None:
                indexes[x, y] = new_color
    for x, y in indexes:
        pixels[x, y] = indexes[x, y]


def pop_art(path_orig, path_mod, coef):

    s=[]
    for i in range(9):

        r=(randint(0,255), randint(0,255), randint(0,255))
        g=(randint(0,255), randint(0,255), randint(0,255))
        b=(randint(0,255), randint(0,255), randint(0,255))

        image_orig = Image.open(path_orig)
        size = image_orig.size
        image_mod = Image.new("RGB",(size[0],size[1]))
        pixels_orig = image_orig.load()
        pixels_mod = image_mod.load()
        for x in range(size[0]):
            for y in range(size[1]):
                p = pixels_orig[x, y]
                if isinstance(p, int):
                    rgb = (p,p,p)
                elif isinstance(p, tuple) and len(p) in (3, 4):
                    rgb = p[:3]
                else:
                    raise TypeError('Unknown pallete')
                average_color = sum(rgb) / 3
                if average_color <= 85:
                    pixels_mod[x, y] = r
                elif 85 < average_color <= 170:
                    pixels_mod[x, y] = g
                elif average_color > 170:
                    pixels_mod[x, y] = b
        for _ in range(coef):
            filter_art(pixels_mod, size)
        image_mod.save(''+dir_path+'\\PopArt\\Modified Images\\result'+str(i)+'.png')
        Img=[None]*9
    for i in range(9):
        Img[i]=Image.open(""+dir_path+"\\PopArt\\Modified Images\\result"+str(i)+".png")
        basewidth = int(Img[i].size[1]/3)
        wpercent = (basewidth / float(Img[i].size[0]))
        hsize = int((float(Img[i].size[1]) * float(wpercent )))
        Img[i] = Img[i].resize((basewidth , hsize ), PIL.Image.ANTIALIAS)
        Img[i].save(''+dir_path+'\\PopArt\\Resized Images\\resized_image'+str(i)+'.png')


    Img1=[None]*9
    pixels1=[None]*9
    Imaz=Image.new("RGB",(basewidth*3,hsize*3))
    pixels=Imaz.load()
    for i in range(9):
        Img1[i]=Image.open(''+dir_path+'\\PopArt\\Resized Images\\resized_image'+str(i)+'.png')
        pixels1[i]=Img1[i].load()


    for x in range(0,basewidth):
        for y in range(0,hsize):
            pixels[x,y]=pixels1[0][x,y]
        for y in range(hsize,hsize*2):
            pixels[x,y]=pixels1[1][x,y-hsize]
        for y in range(hsize*2,hsize*3):
            pixels[x,y]=pixels1[2][x,y-hsize*2]

    for x in range(basewidth,basewidth*2):
        for y in range(0,hsize):
            pixels[x,y]=pixels1[3][x-basewidth,y]
        for y in range(hsize,hsize*2):
            pixels[x,y]=pixels1[4][x-basewidth,y-hsize]
        for y in range(hsize*2,hsize*3):
            pixels[x,y]=pixels1[5][x-basewidth,y-hsize*2]

    for x in range(basewidth*2,basewidth*3):
        for y in range(0,hsize):
            pixels[x,y]=pixels1[6][x-basewidth*2,y]
        for y in range(hsize,hsize*2):
            pixels[x,y]=pixels1[7][x-basewidth*2,y-hsize]
        for y in range(hsize*2,hsize*3):
            pixels[x,y]=pixels1[8][x-basewidth*2,y-hsize*2]
    Imaz = Imaz.resize((size[0] , size[1] ), PIL.Image.ANTIALIAS)
    Imaz.save(""+dir_path+"\\PopArt\\Result Image\\result.png")


def usepop():
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\traitement.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)
    pop_art(a, None, coef=4)
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\PopArt\\Result Image\\result.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)

def change_contrast(level):

    img = Image.open(a)
    img.load()

    factor = (259 * (level+255)) / (255 * (259-level))
    for x in range(img.size[0]):
        for y in range(img.size[1]):
            color = img.getpixel((x, y))
            new_color = tuple(int(factor * (c-128) + 128) for c in color)
            img.putpixel((x, y), new_color)

    return img

def use_contrast():
    result = change_contrast(S2.get())
    result.save(""+dir_path+"ImageMod.png")
    im2 = ImageTk.PhotoImage(file=""+dir_path+"ImageMod.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)

def recherche_contours():
    Ima2=Image.new("RGB",(z[0],z[1]))
    px=Ima1.load()
    px1=Ima2.load()
    for x in range(z[0]):
        for y in range(z[1]):
            p=px[x,y]
            o=int((p[0]+p[1]+p[2])/3)
            px1[x,y]=(o,o,o)
    Ima2 = Ima2.filter(ImageFilter.FIND_EDGES)
    Ima2.save(""+dir_path+"ImageMod.png")
    im2 = ImageTk.PhotoImage(file=""+dir_path+"ImageMod.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)




main=Tk()

main.withdraw()
a = filedialog.askopenfilename()
main.deiconify()

dir_path = os.path.dirname(os.path.realpath("Test2.py"))

main.configure(background="#a1dbcd")
main.title("Photoshop Version.Megzari")

Ima1=Image.open(a)
z=Ima1.size
nux=Image.new("RGB",(z[0],z[1]))
nuxy=nux.load()
for x in range(z[0]):
    for y in range(z[1]):
        nuxy[x,y]=(255,255,255)
nux.save("Blank.png")








if z>(400,400):
    main.withdraw()
    tkMessageBox.showinfo( "Resolution Error", "The image is too big, please select a smaller one.")
    sys.exit()


elif z<(400,400):
    im1 = ImageTk.PhotoImage(file=a)
    I1 = Tkinter.Label(main, image=im1)
    I1.grid(row=0, column=1, columnspan =3)
    imt = ImageTk.PhotoImage(file="Blank.png")
    T1 = Tkinter.Label(main, image=imt)
    T1.grid(row=0, column=4, columnspan =4)
    B1 = Tkinter.Button(main, text ="Echelle de gris", command = EchelleDeGris, fg="#a1dbcd", bg="#383a39", state=NORMAL)
    B1.grid(padx=20, pady=20, row=1, column=0)
    B3 = Tkinter.Button(main, text ="Appliquer Luminosité", command = Luminosite, fg="#a1dbcd", bg="#383a39")
    B3.grid(padx=20, pady=20, row=1, column=1)
    S1 = Scale(main, from_=0, to=254, orient=HORIZONTAL, fg="#a1dbcd", bg="#383a39", length = 200)
    S1.grid(row=2, column=1)
    B2 = Tkinter.Button(main, text ="Supprimer Image", command = SupprimerImage, fg="#a1dbcd", bg="#383a39")
    B2.grid(padx=20, pady=20, row=1, column=7)
    B3 = Tkinter.Button(main, text ="Annuler Modifications", command = AnnulerModifications, fg="#a1dbcd", bg="#383a39")
    B3.grid(padx=20, pady=20, row=1, column=6)
    B4 = Tkinter.Button(main, text ="Pop Art", command = usepop, fg="#a1dbcd", bg="#383a39")
    B4.grid(padx=20, pady=20, row=1, column=3)
    S2 = Scale(main, from_=-258, to=258, orient=HORIZONTAL, fg="#a1dbcd", bg="#383a39", length = 200)
    S2.grid(row=2, column=4)
    B4 = Tkinter.Button(main, text ="Appliquer Contraste", command = use_contrast, fg="#a1dbcd", bg="#383a39")
    B4.grid(padx=20, pady=20, row=1, column=4)
    B5 = Tkinter.Button(main, text ="Trouver Contours", command = recherche_contours, fg="#a1dbcd", bg="#383a39")
    B5.grid(padx=20, pady=20, row=1, column=5)

    s=S1.get()
    s2=S2.get()




main.mainloop()

This is the image I'm trying to display (It's in french in case you were wondering):

I know my variable names are too short, it's a bad habit that I have and I'm trying to get rid of it, so bear with me and my code, I understand it makes it harder for people to understand and so help with this kind of code.

Answer 1

As you mentioned the main issue lies in def usepop() . After loading the image to the label I2 and having issued the command to grid label I2 into position, you ran the function pop_art() . This function then kicked off a cpu intensive activity to convert your image into a pop art. During this 'commotion', your instruction to grid I2 was not carried out, ie it was idle while cpu was busy converting the image. To avoid this problem, issue the command I2.update_idletasks() before activating pop_art() , as shown below. It worked on my system.

def usepop():
    #im2 = ImageTk.PhotoImage(file=""+dir_path+"\\traitement.png")
    print(dir_path)
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\Requirements\\traitement.png") #The image "traitement.png" doesn't get displayed)
    main.image = im2 
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)
    I2.update_idletasks() # Add this to ensure I2.grid is performed first and not remain idle.
    pop_art(a, None, coef=4)
    im2 = ImageTk.PhotoImage(file=""+dir_path+"\\PopArt\\Result Image\\result.png")
    main.image = im2
    I2 = Tkinter.Label(main, image=im2)
    I2.grid(row=0, column=4, columnspan =4)