后台交互逻辑如下：
using System;
using System.Windows;
namespace AForgeTest
{
/// <summary>
/// MainWindow.xaml 的交互逻辑
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void btnOpenCamera_Click(object sender, EventArgs e)
{
CameraHelper.UpdateCameraDevices();
if (CameraHelper.CameraDevices.Count > 0)
{
CameraHelper.SetCameraDevice(0);
}
}
private void btnCapture_Click(object sender, EventArgs e)
{
CameraHelper.CaptureImage(@"E:1");
}
private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
{
CameraHelper.CloseDevice();
}
}
}
CameraHelper 类代码如下：
using System;
using AForge.Video.DirectShow;
using AForge.Controls;
using System.Windows;
using System.IO;
using System.Drawing;
using System.Drawing.Imaging;
namespace AForgeTest
{
public static class CameraHelper
{
private static FilterInfoCollection _cameraDevices;
private static VideoCaptureDevice div = null;
private static VideoSourcePlayer sourcePlayer = new VideoSourcePlayer();
private static bool _isDisplay = false;
//指示_isDisplay设置为true后，是否设置了其他的sourcePlayer，若未设置则_isDisplay重设为false
private static bool isSet = false;
/// <summary>
/// 获取或设置摄像头设备，无设备为null
/// </summary>
public static FilterInfoCollection CameraDevices
{
get
{
return _cameraDevices;
}
set
{
_cameraDevices = value;
}
}
/// <summary>
/// 指示是否显示摄像头视频画面
/// 默认false
/// </summary>
public static bool IsDisplay
{
get { return _isDisplay; }
set { _isDisplay = value; }
}
/// <summary>
/// 获取或设置VideoSourcePlayer控件，
/// 只有当IsDisplay设置为true时，该属性才可以设置成功
/// </summary>
public static VideoSourcePlayer SourcePlayer
{
get { return sourcePlayer; }
set
{
if (_isDisplay)
{
sourcePlayer = value;
isSet = true;
}
}
}
/// <summary>
/// 更新摄像头设备信息
/// </summary>
public static void UpdateCameraDevices()
{
_cameraDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);
}
/// <summary>
/// 设置使用的摄像头设备
/// </summary>
/// <param name="index">设备在CameraDevices中的索引</param>
/// <returns><see cref="bool"/></returns>
public static bool SetCameraDevice(int index)
{
if (!isSet) _isDisplay = false;
//无设备，返回false
if (_cameraDevices.Count <= 0 || index < 0) return false;
if (index > _cameraDevices.Count - 1) return false;
// 设定初始视频设备
div = new VideoCaptureDevice(_cameraDevices[index].MonikerString);
sourcePlayer.VideoSource = div;
div.Start();
sourcePlayer.Start();
return true;
}
/// <summary>
/// 截取一帧图像并保存
/// </summary>
/// <param name="filePath">图像保存路径</param>
/// <param name="fileName">保存的图像文件名</param>
public static void CaptureImage(string filePath, string fileName = null)
{
if (sourcePlayer.VideoSource == null) return;
if (!Directory.Exists(filePath))
{
Directory.CreateDirectory(filePath);
}
try
{
//sourcePlayer.Start();
Image bitmap = sourcePlayer.GetCurrentVideoFrame();
if(fileName == null) fileName = DateTime.Now.ToString("yyyy-MM-dd-HH-mm-ss");
bitmap.Save(filePath + @"" + fileName + "-cap.jpg", ImageFormat.Jpeg);
bitmap.Dispose();
//sourcePlayer.Stop();
}
catch (Exception e)
{
MessageBox.Show(e.Message.ToString());
}
}
/// <summary>
/// 关闭摄像头设备
/// </summary>
public static void CloseDevice()
{
if (div != null && div.IsRunning)
{
sourcePlayer.Stop();
div.SignalToStop();
div = null;
_cameraDevices = null;
}
}
}
}
