使用矩形在图像上创建搜索区域

我有一个显示图像的图像查看器。我想使用鼠标在图像上绘制一个矩形，并获取矩形的 x 和 y 坐标（X1、X2、Y1 和 Y2）。我将使用这些坐标创建一个搜索区域，并在数组中查找最大值和最小值，该数组的两个轴上的像素数与图像的像素数完全相同。
有人可以指导我开始的方向吗？

您应该使用画布来显示图像并在其上绘制一个矩形。

Example:

主窗口.xaml：

<Window x:Class="CanvasRectangleSample.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow">
    <Grid>
        <Canvas x:Name="SampleImageCanvas" 
                MouseMove="SampleImageCanvas_MouseMove" 
                MouseDown="SampleImageCanvas_MouseDown"
                Width="512" Height="389"> 
            <Canvas.Background>
                <!--Here you set the image to display -> You probably want to bind it to something. -->
                <ImageBrush x:Name="SampleImage" Stretch="Uniform" ImageSource="C:\Users\Public\Pictures\Sample Pictures\Koala.jpg">
                </ImageBrush>
            </Canvas.Background>
            <!-- Here you draw whatever you want on the canvas. -->
            <!-- You'll probably want to bind its width and height to something too. -->
            <Rectangle x:Name="ROI" Stroke="#FFF1133E"  Width="50" Height="50"/>
        </Canvas>
    </Grid>
</Window>

MainWindow.xaml.cs：

using System.Windows;
using System.Windows.Input;
using System.Windows.Controls;
namespace CanvasRectangleSample
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            this.DataContext = this;
            InitializeComponent();
        }

        // Handling the redrawing of the rectangle according to mouse location
        private void SampleImageCanvas_MouseMove(object sender, MouseEventArgs e)
        {
            //get mouse location relative to the canvas
            Point pt = e.MouseDevice.GetPosition(sender as Canvas);

            //here you set the rectangle loction relative to the canvas
            Canvas.SetLeft(ROI, pt.X - (int)(ROI.Width / 2));
            Canvas.SetTop(ROI, pt.Y - (int)(ROI.Height / 2));
        }


        private void SampleImageCanvas_MouseDown(object sender, MouseButtonEventArgs e)
        {
            //Here you should handle saving the rectangle location

            //don't forget to calculate the proportion between Canvas's size and real Image's size.

        }
    }

}

如果您愿意，可以使用 if 表达式检查画布区域是否包含鼠标位置，将矩形重定位限制为画布区域