winform 调用摄像头扫码识别二维码
因为公司业务需求,需要在Windows系统下调用摄像头识别二维码需求,就有了这个功能。
我根据网上网友提供的一些资料,自己整合应用到项目中,效果还不错(就是感觉像素不是太好)
现在将调用摄像头+识别二维码这两个功能单独出来写到这里,供大家讨论和参考。
有什么不足或者问题大家可以提出来,共同改进共同进步
创建一个空的winform项目解决方案,我起名叫他:ScanQRCode
将Form1作为主窗体,设置相关属性:
StartPosition:CenterScreen (窗体居中)
添加一个居中标题:
1 private void LoadTitleCenterData() 2 { 3 string titleMsg ="二维码识别主界面"; 4 Graphics g = this.CreateGraphics(); 5 Double startingPoint = (this.Width / 2) - (g.MeasureString(titleMsg, this.Font).Width / 2); 6 Double widthOfASpace = g.MeasureString(" ", this.Font).Width; 7 String tmp = " "; 8 Double tmpWidth = 0; 9 10 while ((tmpWidth + widthOfASpace) < startingPoint) 11 { 12 tmp += " "; 13 tmpWidth += widthOfASpace; 14 } 15 this.Text = tmp + titleMsg; 16 }
最大最小化禁用:
1 public Form1() 2 { 3 this.MinimizeBox = false; 4 this.MaximizeBox = false; 5 InitializeComponent(); 6 LoadTitleCenterData(); 7 }
Form1中添加一个TableLayoutPanel,三行三列,比例按照百分比:10%,80%,10%这样
在TableLayoutPanel的80%中再添加一个TableLayoutPanel,还是行比例:20%,80%这样(二八定律)
在TableLayoutPanel中添加Panel,在其中手动在添加几个按钮和label
最终界面这样(能看就行):
添加一个二维码识别界面CameraQR:
使用Nuget添加引用,搜索AForge,将如下程序包引入:
添加一个识别二维码的窗体,命名名称为:CameraQR
将VideoSourcePlayer添加到窗体中,Fill显示:
窗体中定义几个私有变量:
1 private AForge.Video.DirectShow.FilterInfoCollection _videoDevices;//摄像设备 2 System.Timers.Timer timer;//定时器 3 CameraHelper _cameraHelper = new CameraHelper();//视屏设备操作类
窗体Load事件中获取拍照设备列表,并将第一个设备作为摄像设备(如有前后两个或多个摄像头,自己去改一下代码,设置成可以选择的,在CameraHelper中的CreateFilterInfoCollection()中):
1 private void CameraQR_Load(object sender, EventArgs e) 2 { 3 // 获取视频输入设备 4 _videoDevices = _cameraHelper.CreateFilterInfoCollection();//获取拍照设备列表 5 if (_videoDevices.Count == 0) 6 { 7 MessageBox.Show("无设备"); 8 this.Dispose(); 9 this.Close(); 10 return; 11 } 12 resultStr = "";//二维码识别字符串清空 13 _cameraHelper.ConnectDevice(videoSourcePlayer1);//连接打开设备 14 }
组件初始化完成之后,添加一个定时任务,用来阶段性识别摄像设备中的图片资源,我写的是每200毫秒去识别一次,如果图片中有二维码,就识别二维码;识别成功之后,关闭窗体,将识别结果返回给上一个界面,此处需要一个有识别二维码程序包
使用Nuget添加引用,搜索ZXing,将如下程序包引入:
代码如下(核心代码基本就这些):
public CameraQR() { this.MinimizeBox = false; this.MaximizeBox = false; InitializeComponent(); LoadTitleCenterData(); CheckForIllegalCrossThreadCalls = false;//多线程中访问窗体控件资源不会异常 AddTimer();//定时识别图片 } private void AddTimer() { timer = new System.Timers.Timer(); timer.Enabled = true; timer.Interval = 200; timer.Start(); timer.Elapsed += new ElapsedEventHandler(PicToQRCode); }
private void PicToQRCode(object sender, ElapsedEventArgs e) { if (_cameraHelper.img == null) return; BinaryBitmap bitmap = null; try { MemoryStream ms = new MemoryStream(); _cameraHelper.img.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); byte[] bt = ms.GetBuffer(); ms.Close(); LuminanceSource source = new RGBLuminanceSource(bt, _cameraHelper.img.Width, _cameraHelper.img.Height); bitmap = new BinaryBitmap(new ZXing.Common.HybridBinarizer(source)); } catch (Exception ex) { return; } Result result=null; try { //开始解码 result = new MultiFormatReader().decode(bitmap); } catch (ReaderException ex) { resultStr = ex.ToString(); } if (result != null) { resultStr = result.Text; this.DialogResult = DialogResult.OK; this.Close(); }
}
窗体关闭时,记得释放定时器 关闭摄像头(不然异常满天飞):
private void CameraQR_FormClosing(object sender, FormClosingEventArgs e) { if (timer != null) { timer.Dispose(); } _cameraHelper.CloseDevice(); }
CameraHelper类:
1 public class CameraHelper 2 { 3 public FilterInfoCollection _videoDevices;//本机摄像硬件设备列表 4 public VideoSourcePlayer _videoSourcePlayer;//视频画布 5 public Bitmap img = null;//全局变量,保存每一次捕获的图像 6 public System.Drawing.Image CaptureImage(VideoSourcePlayer sourcePlayer = null) 7 { 8 9 if (sourcePlayer == null || sourcePlayer.VideoSource == null) 10 { 11 if (_videoSourcePlayer == null) 12 return null; 13 else 14 { 15 sourcePlayer = _videoSourcePlayer; 16 } 17 } 18 19 try 20 { 21 if (sourcePlayer.IsRunning) 22 { 23 System.Drawing.Image bitmap = sourcePlayer.GetCurrentVideoFrame(); 24 return bitmap; 25 } 26 return null; 27 28 } 29 catch (Exception ex) 30 { 31 return null; 32 } 33 } 34 35 public FilterInfoCollection CreateFilterInfoCollection() 36 { 37 if (_videoDevices != null) 38 return _videoDevices; 39 _videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice); 40 return _videoDevices; 41 } 42 43 public VideoCaptureDevice ConnectDevice(VideoSourcePlayer videoSourcePlayer, FilterInfo filterInfo = null) 44 { 45 VideoCaptureDevice videoSource = new VideoCaptureDevice(); 46 if (filterInfo == null) 47 { 48 videoSource = new VideoCaptureDevice(_videoDevices[_videoDevices.Count - 1].MonikerString); 49 } 50 else 51 { 52 videoSource = new VideoCaptureDevice(filterInfo.MonikerString); 53 } 54 55 videoSource.NewFrame += new NewFrameEventHandler(video_NewFrame); 56 videoSourcePlayer.VideoSource = videoSource; 57 videoSourcePlayer.Start(); 58 _videoSourcePlayer = videoSourcePlayer; 59 return videoSource; 60 } 61 62 private void video_NewFrame(object sender, NewFrameEventArgs eventArgs) 63 { 64 img = (Bitmap)eventArgs.Frame.Clone(); 65 } 66 67 public void CloseDevice(VideoSourcePlayer videoSourcePlayer = null) 68 { 69 if (videoSourcePlayer == null) 70 { 71 if (_videoSourcePlayer == null) 72 return; 73 _videoSourcePlayer.SignalToStop(); 74 } 75 else 76 { 77 videoSourcePlayer.SignalToStop(); 78 } 79 } 80 }
我用的测试二维码是:
最终的别结果为:
代码:https://github.com/Binzm/ScanQRCode.git