Using OpenCV with Tkinter
I'm writing a program that needs to display a video stream in a Tkinter window. Since there will also be buttons for performing various functions, I'm using grid to organize where everything goes.
The following code, modified from Show webcam sequence TkInter, works fine on my Raspberry Pi:
import Tkinter as tk
import cv2
from PIL import Image, ImageTk
width, height = 800, 600
cap = cv2.VideoCapture(0)
root = tk.Tk()
lmain = tk.Label(root)
lmain.pack()
def show_frame():
_, frame = cap.read()
frame = cv2.flip(frame, 1)
cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
img = Image.fromarray(cv2image)
imgtk = ImageTk.PhotoImage(image=img)
lmain.imgtk = imgtk
lmain.configure(image=imgtk)
lmain.after(10, show_frame)
show_frame()
root.mainloop()
However, combining it with Tkinter doesn't work. (In what follows, I've tried commenting out Display 1, Display 2, and neither.)
import numpy as np
import cv2
import Tkinter as tk
import Image, ImageTk
#Set up GUI
window = tk.Tk() #Makes main window
window.wm_title("Digital Microscope")
window.config(background="#FFFFFF")
#Graphics window
imageFrame = tk.Frame(window, width=600, height=500)
imageFrame.grid(row=0, column=0, padx=10, pady=2)
#Capture video frames
lmain = tk.Label(imageFrame)
cap = cv2.VideoCapture(0)
def show_frame():
_, frame = cap.read()
frame = cv2.flip(frame, 1)
cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
img = Image.fromarray(cv2image)
imgtk = ImageTk.PhotoImage(image=img)
lmain.imgtk = imgtk
lmain.configure(image=imgtk)
lmain.after(10, show_frame)
tk.Label(imageFrame, image=show_frame()).grid(row=0, column=0, padx=10, pady=2) #Display 1
#Slider window (slider controls stage position)
sliderFrame = tk.Frame(window, width=600, height=100)
sliderFrame.grid(row = 600, column=0, padx=10, pady=2)
show_frame() #Display 2
window.mainloop() #Starts GUI
How can I get the video to display in imageFrame
?
This should work:
import numpy as np
import cv2
import Tkinter as tk
import Image, ImageTk
#Set up GUI
window = tk.Tk() #Makes main window
window.wm_title("Digital Microscope")
window.config(background="#FFFFFF")
#Graphics window
imageFrame = tk.Frame(window, width=600, height=500)
imageFrame.grid(row=0, column=0, padx=10, pady=2)
#Capture video frames
lmain = tk.Label(imageFrame)
lmain.grid(row=0, column=0)
cap = cv2.VideoCapture(0)
def show_frame():
_, frame = cap.read()
frame = cv2.flip(frame, 1)
cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
img = Image.fromarray(cv2image)
imgtk = ImageTk.PhotoImage(image=img)
lmain.imgtk = imgtk
lmain.configure(image=imgtk)
lmain.after(10, show_frame)
#Slider window (slider controls stage position)
sliderFrame = tk.Frame(window, width=600, height=100)
sliderFrame.grid(row = 600, column=0, padx=10, pady=2)
show_frame() #Display 2
window.mainloop() #Starts GUI
First of all, you have the line tk.Label(imageFrame, image=show_frame()).grid(row=0, column=0, padx=10, pady=2)
, and since show_frame()
doesn't return anything, you've set image
to None
. Second of all, you need to make sure you lmain.grid()
, otherwise lmain
won't show.
If you want to have two displays one on top of the other, you could do something like this:
import numpy as np
import cv2
import Tkinter as tk
import Image, ImageTk
#Set up GUI
window = tk.Tk() #Makes main window
window.wm_title("Digital Microscope")
window.config(background="#FFFFFF")
#Graphics window
imageFrame = tk.Frame(window, width=600, height=500)
imageFrame.grid(row=0, column=0, padx=10, pady=2)
#Capture video frames
cap = cv2.VideoCapture(0)
def show_frame():
_, frame = cap.read()
frame = cv2.flip(frame, 1)
cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA)
img = Image.fromarray(cv2image)
imgtk = ImageTk.PhotoImage(image=img)
display1.imgtk = imgtk #Shows frame for display 1
display1.configure(image=imgtk)
display2.imgtk = imgtk #Shows frame for display 2
display2.configure(image=imgtk)
window.after(10, show_frame)
display1 = tk.Label(imageFrame)
display1.grid(row=1, column=0, padx=10, pady=2) #Display 1
display2 = tk.Label(imageFrame)
display2.grid(row=0, column=0) #Display 2
#Slider window (slider controls stage position)
sliderFrame = tk.Frame(window, width=600, height=100)
sliderFrame.grid(row = 600, column=0, padx=10, pady=2)
show_frame() #Display
window.mainloop() #Starts GUI
Try this code:
from PIL import Image, ImageTk
import Tkinter as tk
import argparse
import datetime
import cv2
import os
class Application:
def __init__(self, output_path = "./"):
""" Initialize application which uses OpenCV + Tkinter. It displays
a video stream in a Tkinter window and stores current snapshot on disk """
self.vs = cv2.VideoCapture(0) # capture video frames, 0 is your default video camera
self.output_path = output_path # store output path
self.current_image = None # current image from the camera
self.root = tk.Tk() # initialize root window
self.root.title("PyImageSearch PhotoBooth") # set window title
# self.destructor function gets fired when the window is closed
self.root.protocol('WM_DELETE_WINDOW', self.destructor)
self.panel = tk.Label(self.root) # initialize image panel
self.panel.pack(padx=10, pady=10)
# create a button, that when pressed, will take the current frame and save it to file
btn = tk.Button(self.root, text="Snapshot!", command=self.take_snapshot)
btn.pack(fill="both", expand=True, padx=10, pady=10)
# start a self.video_loop that constantly pools the video sensor
# for the most recently read frame
self.video_loop()
def video_loop(self):
""" Get frame from the video stream and show it in Tkinter """
ok, frame = self.vs.read() # read frame from video stream
if ok: # frame captured without any errors
cv2image = cv2.cvtColor(frame, cv2.COLOR_BGR2RGBA) # convert colors from BGR to RGBA
self.current_image = Image.fromarray(cv2image) # convert image for PIL
imgtk = ImageTk.PhotoImage(image=self.current_image) # convert image for tkinter
self.panel.imgtk = imgtk # anchor imgtk so it does not be deleted by garbage-collector
self.panel.config(image=imgtk) # show the image
self.root.after(30, self.video_loop) # call the same function after 30 milliseconds
def take_snapshot(self):
""" Take snapshot and save it to the file """
ts = datetime.datetime.now() # grab the current timestamp
filename = "{}.jpg".format(ts.strftime("%Y-%m-%d_%H-%M-%S")) # construct filename
p = os.path.join(self.output_path, filename) # construct output path
self.current_image.save(p, "JPEG") # save image as jpeg file
print("[INFO] saved {}".format(filename))
def destructor(self):
""" Destroy the root object and release all resources """
print("[INFO] closing...")
self.root.destroy()
self.vs.release() # release web camera
cv2.destroyAllWindows() # it is not mandatory in this application
# construct the argument parse and parse the arguments
ap = argparse.ArgumentParser()
ap.add_argument("-o", "--output", default="./",
help="path to output directory to store snapshots (default: current folder")
args = vars(ap.parse_args())
# start the app
print("[INFO] starting...")
pba = Application(args["output"])
pba.root.mainloop()