视频供稿中的Pi Camera黑条

Question

我目前正在Raspberry Pi 3上使用Thonny运行此代码。此应用程序将Pi Camera帧的实时提要放到Tkinter Canvas上。然后，用户可以单击“捕获”按钮以捕获并存储框架。 “触摸充电”和“触摸检索”按钮只是在使cancas可见/不可见之间切换。它的功能远不止于此，但就目前而言，我想知道的是为什么这些黑条会显示在供稿上。 谢谢！

到目前为止，这是我的代码

import tkinter
import cv2
import PIL.Image, PIL.ImageTk
import time

state = 0           # state of canvas
inUse = 0           # make inUse = 1 at the end

class App:

    global state
    global inUse



    def __init__(self, window, window_title, video_source=0):
        self.window = window
        self.window.title(window_title)
        self.video_source = video_source

        # open video source (by default this will try to open the computer webcam)
        self.vid = MyVideoCapture(self.video_source)

        # Create a canvas that can fit the above video source size
       # self.canvas = tkinter.Canvas(window, width = self.vid.width, height = self.vid.height)

        self.canvas = tkinter.Canvas(window, width=2000, height=2000)

        # Button that lets the user take a snapshot
        self.btn_snapshot=tkinter.Button(window, text="Snapshot", width=35, command=self.snapshot)

        self.btn_state=tkinter.Button(window, text="Enable/Disable", width=35, command=self.closeWindow)

        # use lambda with command if you need to use anything
        self.chargeBT=tkinter.Button(window, text="Touch to Charge", width=25, height=3, command=self.chargeAction)
        self.retrieveBT=tkinter.Button(window, text="Touch to Retrieve", width=25, height=3, command=self.chargeAction)

        self.btn_snapshot.pack(anchor=tkinter.W)
        self.btn_state.pack(anchor=tkinter.W)
        self.chargeBT.place(relx=0.4, rely=0.8)
        self.retrieveBT.place(relx=0.7, rely=0.8)
        self.canvas.pack(anchor=tkinter.CENTER)

        self.canvas.pack_forget()


        # After it is called once, the update method will be automatically called every delay milliseconds
        self.delay = 15
        self.update()

        self.window.geometry("800x480")
        self.window.mainloop()

    def snapshot(self):
        # Get a frame from the video source
        ret, frame = self.vid.get_frame()

        if ret:
            cv2.imwrite("frame-" + time.strftime("%d-%m-%Y-%H-%M-%S") + ".jpg", cv2.cvtColor(frame, cv2.COLOR_RGB2BGR))

    def closeWindow(self):
        global state

        if state == 0:
            self.canvas.pack()
            state = 1

        else:
            self.canvas.pack_forget()
            state = 0

        #self.window.destroy()

    def update(self):
        # Get a frame from the video source
        ret, frame = self.vid.get_frame()

        if ret:
            frame = cv2.flip(frame,1)

            self.photo = PIL.ImageTk.PhotoImage(image = PIL.Image.fromarray(frame))
            self.canvas.create_image(0, 0, image = self.photo, anchor = tkinter.NW)

        self.window.after(self.delay, self.update)

    def chargeAction(self):
        global inUse

        if inUse == 0:
            print("Im in!!!")
            self.btn_state.configure(text="YOYOYO")
            self.canvas.pack(anchor=tkinter.CENTER)
            inUse = 1

        else:
            print("Sorry this locker is in use")
            self.canvas.pack_forget()
            inUse = 0



class MyVideoCapture:
    def __init__(self, video_source=0):
        # Open the video source
        self.vid = cv2.VideoCapture(video_source)

        rval, frame = self.vid.read()

        self.vid.set(3, 200)
        self.vid.set(4, 200)

        """ change resolution
        cap.set(3,1280)
        cap.set(4,1024)

        """

        if not self.vid.isOpened():
            raise ValueError("Unable to open video source", video_source)

        # Get video source width and height
        self.width = self.vid.get(cv2.CAP_PROP_FRAME_WIDTH)
        self.height = self.vid.get(cv2.CAP_PROP_FRAME_HEIGHT)

    def get_frame(self):
        if self.vid.isOpened():
            ret, frame = self.vid.read()
            if ret:
                # Return a boolean success flag and the current frame converted to BGR
                return (ret, cv2.cvtColor(frame, cv2.COLOR_BGR2RGB))
            else:
                return (ret, None)
        else:
            return (ret, None)

    # Release the video source when the object is destroyed
    def __del__(self):
        if self.vid.isOpened():
            self.vid.release()

# Create a window and pass it to the Application object
App(tkinter.Tk(), "Tkinter and OpenCV")