在WPF程序中使用摄像头兼谈如何使用AForge.NET控件(转)

前言：

AForge.NET 是用C#写的一个关于计算机视觉和人工智能领域的框架，它包括图像处理、神经网络、遗传算法和机器学习等。在C#程序中使用摄像头，我习惯性使用AForge.NET提供的类库。本文讲解如何在WPF程序中调用AForge.NET控件实现视频和抓拍功能。

AForge.NET控件下载地址：http://code.google.com/p/aforge/

WPF与WinForm控件交互：

要实现视频功能，需要使用AForge.Controls命名空间中的VideoSourcePlayer控件。这是一个WinForm控件，要在WPF程序中使用，我们需要做如下4步：

1. 添加引用：

   在.NET选项卡中选择WindowsFormsIntegration

   在浏览选项卡中添加3个AForge.NET类库

   AForge.Controls.dll

   AForge.Video.dll

   AForge.Video.DirectShow.dll

2. 在XAML中添加System.Windows.Forms.Integration命名空间

   [html] view plaincopyprint?

   1. xmlns:wfi ="clr-namespace:System.Windows.Forms.Integration;assembly=WindowsFormsIntegration"

   xmlns:wfi ="clr-namespace:System.Windows.Forms.Integration;assembly=WindowsFormsIntegration"

3. 在XAML中添加AForge.Controls命名空间

   [html] view plaincopyprint?

   1. xmlns:aforge ="clr-namespace:AForge.Controls;assembly=AForge.Controls"

   xmlns:aforge ="clr-namespace:AForge.Controls;assembly=AForge.Controls"

4. 在XAML中加入VideoSourcePlayer可视控件

   [html] view plaincopyprint?

   1. <wfi:WindowsFormsHost Grid.Row="0" Margin="5">
   2. <aforge:VideoSourcePlayer x:Name="sourcePlayer" Width="300" Height="360">
   3. </aforge:VideoSourcePlayer>
   4. </wfi:WindowsFormsHost>

   <wfi:WindowsFormsHost Grid.Row="0" Margin="5">
       <aforge:VideoSourcePlayer x:Name="sourcePlayer" Width="300" Height="360">
       </aforge:VideoSourcePlayer>
   </wfi:WindowsFormsHost>

演示程序界面：

开发工具：

• Visual Studio v2010

• .NET Framework 4 Client Profile

• AForge.NET Framework 2.1.5

工程文件下载：

FingerPictureBox_WPF_Solution.zip

源程序：
MainWindow.xaml

<Window x:Class="FaceCapture.MainWindow"

        xmlns:wfi ="clr-namespace:System.Windows.Forms.Integration;assembly=WindowsFormsIntegration"

        xmlns:aforge ="clr-namespace:AForge.Controls;assembly=AForge.Controls"

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

        xmlns:my="clr-namespace:Splash;assembly=FingerPictureBox"

        Title="FaceCapture（WPF）" mc:Ignorable="d" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" d:DesignHeight="480" d:DesignWidth="902" SizeToContent="WidthAndHeight" WindowStartupLocation="CenterScreen" ResizeMode="CanMinimize" AllowDrop="True" Closing="Window_Closing">

    <Grid AllowDrop="True">     

        <Grid.ColumnDefinitions>

            <ColumnDefinition />

            <ColumnDefinition />

        </Grid.ColumnDefinitions>

        <Grid Grid.Column="0" AllowDrop="False">

            <Grid.RowDefinitions>

                <RowDefinition />

                <RowDefinition />

            </Grid.RowDefinitions>            

            <wfi:WindowsFormsHost Grid.Row="0" Margin="5">

                <aforge:VideoSourcePlayer x:Name="sourcePlayer" Width="300" Height="360">                    

                </aforge:VideoSourcePlayer>                

            </wfi:WindowsFormsHost>

            <StackPanel Grid.Row="1" Orientation="Horizontal" Height="60" HorizontalAlignment="Stretch" >

                <Button Name="button_Play" Height="40" Width="120" Margin="40,10,20,10" Click="button_Play_Click">

                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center">

                        <Image Name="image_Play" Width="32" Height="32" />

                        <Label Name="label_Play" Content="开启摄像头" VerticalContentAlignment="Center" FontSize="14" />                     

                    </StackPanel>                    

                </Button>

                <Button Name="button_Capture" Height="40" Width="120" Margin="40,10,40,10" Click="button_Capture_Click">

                    <StackPanel Orientation="Horizontal" VerticalAlignment="Center">

                        <Image Name="image_Capture" Width="32" Height="32" />

                        <Label Content="抓拍图像" VerticalContentAlignment="Center" FontSize="14" />

                    </StackPanel>

                </Button> 

            </StackPanel>            

        </Grid>   

        <Grid Grid.Column="1">

            <Grid.RowDefinitions>

                <RowDefinition />

                <RowDefinition />

            </Grid.RowDefinitions>

            <StackPanel Grid.Row="0" Orientation="Horizontal">

                <my:FingerPictureBox Height="210" Name="fingerPictureBox1" Width="210" BorderThickness="5" BorderBrush="DarkGreen" Margin="5" />

                <my:FingerPictureBox Height="210" Name="fingerPictureBox2" Width="210" BorderThickness="5" BorderBrush="DarkGreen" Margin="5" />

            </StackPanel>

            <StackPanel Grid.Row="1" Orientation="Horizontal">

                <my:FingerPictureBox Height="210" Name="fingerPictureBox3" Width="210" BorderThickness="5" BorderBrush="DarkGreen" Margin="5" />

                <my:FingerPictureBox Height="210" Name="fingerPictureBox4" Width="210" BorderThickness="5" BorderBrush="DarkGreen" Margin="5" />

            </StackPanel>

        </Grid>        

    </Grid>

</Window>

MainWindow.xaml.cs

using System;

using System.Windows;

using System.Windows.Media.Imaging;

using AForge.Video.DirectShow;

using Splash;

namespace FaceCapture

{

    /// <summary>

    /// MainWindow.xaml 的交互逻辑

    /// </summary>

    public partial class MainWindow : Window

    {

        BitmapSource ImagePlay;

        BitmapSource ImageStop;

        public MainWindow()

        {

            InitializeComponent();

            // 设置窗体图标

            this.Icon = System.Windows.Interop.Imaging.CreateBitmapSourceFromHIcon(

                Properties.Resources.FingerPictureBox.Handle,

                Int32Rect.Empty,

                BitmapSizeOptions.FromEmptyOptions());

            // 图像源初始化

            ImagePlay = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(

                Properties.Resources.Button_Play_icon2.GetHbitmap(),

                IntPtr.Zero,

                Int32Rect.Empty,

                BitmapSizeOptions.FromEmptyOptions());

            ImageStop = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(

                Properties.Resources.Button_Stop_icon.GetHbitmap(),

                IntPtr.Zero,

                Int32Rect.Empty,

                BitmapSizeOptions.FromEmptyOptions());

            // 设置按钮图像

            image_Play.Source = ImagePlay;

            image_Capture.Source = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(

                Properties.Resources.capture.GetHbitmap(),

                IntPtr.Zero,

                Int32Rect.Empty,

                BitmapSizeOptions.FromEmptyOptions());            

            // 设置窗体装载后事件处理器

            this.Loaded += new RoutedEventHandler(MainWindow_Loaded);

        }

        private void MainWindow_Loaded(object sender, RoutedEventArgs e)

        {

            // 设定初始视频设备

            FilterInfoCollection videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);

            if (videoDevices.Count > 0)

            {   // 默认设备

                sourcePlayer.VideoSource = new VideoCaptureDevice(videoDevices[0].MonikerString);                

            }

            else

            {

                button_Play.IsEnabled = false;

                button_Capture.IsEnabled = false;

            }

            // 设置图片框初始图像

            BitmapSource bs = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(

                Properties.Resources.noimage.GetHbitmap(),

                IntPtr.Zero,

                Int32Rect.Empty,

                BitmapSizeOptions.FromEmptyOptions());

            fingerPictureBox1.InitialImage = bs;

            fingerPictureBox2.InitialImage = bs;

            fingerPictureBox3.InitialImage = bs;

            fingerPictureBox4.InitialImage = bs;

        }

        private void button_Play_Click(object sender, RoutedEventArgs e)

        {            

            if (image_Play.Source == ImagePlay)

            {   // 开启视频

                sourcePlayer.Start();

                if (sourcePlayer.IsRunning)

                {

                    // 改变按钮为“停止”状态

                    image_Play.Source = ImageStop;

                    label_Play.Content = "停止";

                    // 允许拍照

                    button_Capture.IsEnabled = true;

                }

            }  

            else

            {

                if (sourcePlayer.IsRunning)

                {   // 停止视频

                    sourcePlayer.SignalToStop();

                    sourcePlayer.WaitForStop();

                    // 改变按钮为“开始”状态

                    image_Play.Source = ImagePlay;

                    label_Play.Content = "开启摄像头"; ;

                    // 关闭拍照

                    button_Capture.IsEnabled = false;

                }                

            }

        }

        private void button_Capture_Click(object sender, RoutedEventArgs e)

        {

            // 判断视频设备是否开启

            if (sourcePlayer.IsRunning)

            {   // 进行拍照

                for (Int32 i = 1; i <= 4; i++)

                {

                    object box = this.FindName("fingerPictureBox" + i);

                    if(box is FingerPictureBox)

                    {

                        if ((box as FingerPictureBox).ActiveImage == (box as FingerPictureBox).InitialImage)

                        {   // 更新图像

                            (box as FingerPictureBox).ActiveImage = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(

                                sourcePlayer.GetCurrentVideoFrame().GetHbitmap(),

                                IntPtr.Zero,

                                Int32Rect.Empty,

                                BitmapSizeOptions.FromEmptyOptions());

                            break;

                        }                    

                    }

                }

            }

        }

        private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)

        {

            if (sourcePlayer.IsRunning)

            {   // 停止视频

                sourcePlayer.SignalToStop();

                sourcePlayer.WaitForStop();

            }

        }

    }

}