Tkinter 画布不显示背景

如何解决Tkinter 画布不显示背景

有人可以告诉我为什么它不显示背景吗？我在这里做错了什么？它显示的是空白屏幕，而不是我的背景。

from tkinter import *

def main_menu_create(para):
    myimage = PhotoImage(file = "background1.png")
    main_screen = Canvas(root,width=1280,height=720,bg='black')
    main_screen.place(x=0,y=0)
    main_screen.create_image(0,image=myimage,anchor='nw')
    main_screen.create_text(625,100,font="Timesnewroman 50 bold",fill='red',text='Flappy Bird')

    start_button = Button(main_screen,text="Start Flapping!!",relief='ridge',width=25,bd=2,font='Helvitica 20',fg='white',bg='brown',activebackground='orange')
    start_button.place(x=625,y=300,anchor='center')

    start_button = Button(main_screen,text="Options",y=380,text="Change Background",y=460,text="Exit game",activebackground='orange',command = para.destroy)
    start_button.place(x=625,y=540,anchor='center')

root = Tk()
root.geometry("1280x720")
main_menu_create(root)

root.mainloop()