如何使用tkinter画布显示图像，两个图像均不显示

Question

我想使用filedialog.askopenfilename（）从用户那里获得2张图像 并排显示在屏幕上，我可以读取图像，但是在GUI中图像没有显示

root = Tk()
root.geometry("%dx%d" % (400, 300))
root.title("BMP Image GUI")
canvas = Canvas(root)

def IdUpload():

  global ID_Photo_filename

 ID_Photo_filename=filedialog.askopenfilename()
 load=Image.open(ID_Photo_filename)
 w, h = load.size
 Id_img=ImageTk.PhotoImage(load)
 Show_Id=canvas.create_image((w / 2, h / 2), image=Id_img)
 root.geometry("%dx%d" % (w/2, h/2))


def PhotoUpload():
 global Photo_filename

 Photo_filename=filedialog.askopenfilename()
 load_photo=Image.open(Photo_filename)
 w,h=load_photo.size

 Photo_img=ImageTk.PhotoImage(load_photo)
 Show_Photo=canvas.create_image((w / 2, h / 2), image=Photo_img)
 root.geometry("%dx%d" % (w/2, h/2))

UserName=Label(root,text="UserName")
UserName.pack(side=LEFT)

EnterName=Entry(root)
EnterName.pack(side=LEFT)

canvas.pack(fill=tk.BOTH, expand=True) 


Id_Upload = Button(root, text="Upload Id", command=IdUpload)
Photo_Upload = Button(root, text="Upload Photo", command=PhotoUpload)
Compare_photo = Button(root, text="Compare", command=ComparePhoto)

Id_Upload.pack(side=LEFT)
Compare_photo.pack(side=LEFT)

Photo_Upload.pack(side=LEFT)

root.mainloop()

我已经显示了部分代码，我认为如果需要的话，我会发布完整的代码