Something

from Tkinter import * 
import time                  
root = Tk()

canvas = Canvas(root, width=50, height=50)
canvas.pack(fill=BOTH)

class Hello(Frame):                     
	def __init__(self, parent=None):    
		Frame.__init__(self, parent)
		self.pack()
		self.make_widgets()
		self.status()

		
		
	def make_widgets(self):             
		widget = Button(self, text='Start image processing', command=self.start)
		widget.pack(side=TOP)
		widget.configure(state=DISABLED, background='cadetblue')
		widget.configure(state=NORMAL, background='red')
		widget2 = Button(self, text='Stop image processing', command=self.stop)
		widget2.pack(side=TOP)
		widget2.configure(state=DISABLED, background='cadetblue')
		widget2.configure(state=NORMAL, background='red')

	def start(self):
		canvas.itemconfigure(self.square, fill="green")
		while 1 < 2:
			time.sleep(3)
			print "started"
		
	
	def stop(self):
		canvas.itemconfigure(self.square, fill="red")
		event.bind(self.run, self.stop)
		print "stopped"
	
	def status(self):
		self.square = canvas.create_rectangle(10,10,30,30, fill="red")		
		
	def stop(self):
		root.destroy()
		
if __name__ == '__main__':  Hello().mainloop()