如何在WPF中做图片形状的按钮？

<Window x:Class="CustomImageButton.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Custom Image Button Example" Height="350" Width="525">
    <Window.Resources>
        <!-- 定义按钮模板 -->
        <ControlTemplate x:Key="RoundImageButtonTemplate" TargetType="{x:Type Button}">
            <Grid>
                <Ellipse x:Name="ButtonBackground" Fill="LightBlue" Width="100" Height="100"/>
                <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center">
                    <ContentPresenter.Content>
                        <Image Source="path_to_your_image.png" Width="80" Height="80"/>
                    </ContentPresenter.Content>
                </ContentPresenter>
            </Grid>
            <ControlTemplate.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter TargetName="ButtonBackground" Property="Fill" Value="LightGreen"/>
                </Trigger>
                <Trigger Property="IsPressed" Value="True">
                    <Setter TargetName="ButtonBackground" Property="Fill" Value="LightYellow"/>
                </Trigger>
            </ControlTemplate.Triggers>
        </ControlTemplate>
    </Window.Resources>
    <Grid>
        <!-- 使用自定义模板创建按钮 -->
        <Button Template="{StaticResource RoundImageButtonTemplate}" Width="100" Height="100" Margin="20"/>
    </Grid>
</Window>

<Viewbox>
    <Image Source="path_to_your_image.png" Width="80" Height="80"/>
</Viewbox>