Python Tkinter。数据点的最佳拟合椭圆

Question

我正在使用 Tkinter 开发 Python GUI。我试图将 BMP 图像中的四个指定点位置保存到变量中，并创建一个或多或少穿过保存点的最佳拟合椭圆。我仍然是使用 Tkinter 和 GUI 的初学者，所以请耐心等待!

到目前为止，代码能够标记点并打印出其位置/坐标。对于这种情况我应该使用 matplotlib 吗？我也可以使用 tkinter 吗？

这是我的代码:

from tkinter import *
from PIL import Image, ImageTk

class Window(Frame):

    def __init__(self, master=None):
        Frame.__init__(self, master)

        self.master = master
        self.pos = []
        self.master.title("GUI")
        self.pack(fill=BOTH, expand=1)

        self.counter = 0

        menu = Menu(self.master)
        self.master.config(menu=menu)

        file = Menu(menu)
        file.add_command(label="Exit", command=self.client_exit)
        menu.add_cascade(label="File", menu=file)
        analyze = Menu(menu)

        analyze.add_command(label="Region of 
        Interest",command=self.regionOfInterest)
        analyze.add_command(label="Erase", command=self.erasePoints)

        menu.add_cascade(label="Analyze", menu=analyze)
        load = Image.open("ap41.ddr.brf.sdat.bmp")
        render = ImageTk.PhotoImage(load)

        img = Label(self, image=render)
        img.image = render
        img.place(x=0, y=0)

    def regionOfInterest(self):
        root.config(cursor="plus")
        canvas.bind("<Button-1>", self.imgClick)

    def erasePoints(self):
        self.pos = []

    def client_exit(self):
        exit()

    def imgClick(self, event):

        if self.counter < 4:
            x = canvas.canvasx(event.x)
            y = canvas.canvasy(event.y)
            self.pos.append((x, y))
            print(self.pos)
            canvas.create_line(x - 5, y, x + 5, y, fill="red", 
tags="crosshair")
            canvas.create_line(x, y - 5, x, y + 5, fill="red", 
tags="crosshair")
            self.counter += 1
        else:
            canvas.unbind("<Button 1>")
            root.config(cursor="arrow")
            self.counter = 0


root = Tk()
imgSize = Image.open("ap41.ddr.brf.sdat.bmp")
tkimage =  ImageTk.PhotoImage(imgSize)
w, h = imgSize.size

canvas = Canvas(root, width=w, height=h)
canvas.create_image((w/2,h/2),image=tkimage)
canvas.pack()

root.geometry("%dx%d"%(w,h))
app = Window(root)
root.mainloop()

Answer 1

这是您可以使用和微调的东西，但我认为这将接近您想要做的事情。

首先，我创建了另一个标记为Create Ellipse的菜单项，该菜单项链接到计算左上角线和右下线的方法，然后将其与create_ovel()一起使用> 命令在屏幕上创建一个椭圆。让我知道这是否接近您想要做的事情。

下面的新方法会将每个元组的值与基本元组进行比较，如果数字较低，则会更改左上角的线，如果数字较高，则会更改右下角的线。弄清楚这两组线后，它将创建一个椭圆形以大致适合您选择的内容。

def createEllipse(self):

    top_left_cords = self.pos[0]
    bottom_right_cords = self.pos[0]
    for pos in self.pos:
        if pos[0] < top_left_cords[0]:
            top_left_cords = (pos[0], top_left_cords[1])

        if pos[1] < top_left_cords[1]:
            top_left_cords = (top_left_cords[0], pos[1])

        if pos[0] > bottom_right_cords[0]:
            bottom_right_cords = (pos[0], bottom_right_cords[1])

        if pos[1] > bottom_right_cords[1]:
            bottom_right_cords = (bottom_right_cords[0], pos[1])

完整代码如下:

from tkinter import *
from PIL import Image, ImageTk

class Window(Frame):

    def __init__(self, master=None):
        Frame.__init__(self, master)

        self.master = master
        self.pos = []
        self.master.title("GUI")
        self.pack(fill=BOTH, expand=1)

        self.counter = 0

        menu = Menu(self.master)
        self.master.config(menu=menu)

        file = Menu(menu)
        file.add_command(label="Exit", command=self.client_exit)
        menu.add_cascade(label="File", menu=file)
        analyze = Menu(menu)

        analyze.add_command(label="Region of Interest",command=self.regionOfInterest)
        analyze.add_command(label="Erase", command=self.erasePoints)
        analyze.add_command(label="Create Ellipse", command=self.createEllipse)

        menu.add_cascade(label="Analyze", menu=analyze)
        load = Image.open("./Colors/1.png")
        render = ImageTk.PhotoImage(load)


        img = Label(self, image=render)
        img.image = render
        img.place(x=0, y=0)

    def createEllipse(self):

        top_left_cords = self.pos[0]
        bottom_right_cords = self.pos[0]
        for pos in self.pos:
            if pos[0] < top_left_cords[0]:
                top_left_cords = (pos[0], top_left_cords[1])

            if pos[1] < top_left_cords[1]:
                top_left_cords = (top_left_cords[0], pos[1])

            if pos[0] > bottom_right_cords[0]:
                bottom_right_cords = (pos[0], bottom_right_cords[1])

            if pos[1] > bottom_right_cords[1]:
                bottom_right_cords = (bottom_right_cords[0], pos[1])

        print(top_left_cords, bottom_right_cords)

        canvas.create_oval(top_left_cords, bottom_right_cords)

    def regionOfInterest(self):
        root.config(cursor="plus")
        canvas.bind("<Button-1>", self.imgClick)

    def erasePoints(self):
        self.pos = []

    def client_exit(self):
        exit()

    def imgClick(self, event):

        if self.counter < 4:
            x = canvas.canvasx(event.x)
            y = canvas.canvasy(event.y)
            self.pos.append((x, y))
            print(self.pos)
            canvas.create_line(x - 5, y, x + 5, y, fill="red", 
tags="crosshair")
            canvas.create_line(x, y - 5, x, y + 5, fill="red", 
tags="crosshair")
            self.counter += 1
        else:
            canvas.unbind("<Button 1>")
            root.config(cursor="arrow")
            self.counter = 0


root = Tk()
imgSize = Image.open("./Colors/1.png")
tkimage =  ImageTk.PhotoImage(imgSize)
w, h = imgSize.size

canvas = Canvas(root, width=w, height=h)
canvas.create_image((w/2,h/2),image=tkimage)
canvas.pack()

root.geometry("%dx%d"%(w,h))
app = Window(root)
root.mainloop()

这是我用于测试的示例图像的前后对比。

之前:

之后: