原文:
C# WPF 显示图片和视频显示 EmuguCv、AForge.Net测试
WPF 没有用到 PictureBox, 而是用Image代替.
下面我试着加载显示一个图片 。
XAML
<Image x:Name="srcImg"Width="400"Height="300"></Image>CS Attempt 1:
Image<Bgr,Byte>My_Image=newImage<Bgr,byte>(Openfile.FileName);
srcImg.Source=My_Image.ToBitmap();Error Message
Cannot implicitly convert type 'System.Drawing.Bitmap'
to 'System.Windows.Media.ImageSource'CS Attempt 2:
Image<Bgr,Byte>My_Image=newImage<Bgr,byte>(Openfile.FileName);
srcImg.Source=newBitmapImage(My_Image);Error Message
Error1The best overloaded method match for'System.Windows.Media.Imaging.BitmapImage.BitmapImage(System.Uri)' has some invalid arguments Error2Argument1: cannot convert from'Emgu.CV.Image<Emgu.CV.Structure.Bgr,byte>' to 'System.Uri'
解决方法：
Image<Bgr, Byte> My_Image = new Image<Bgr, byte>(Openfile.FileName); srcImg.Source = BitmapSourceConvert.ToBitmapSource(myImage);
public static class BitmapSourceConvert { [DllImport("gdi32")] private static extern int DeleteObject(IntPtr o); public static BitmapSource ToBitmapSource(IImage image) { using (System.Drawing.Bitmap source = image.Bitmap) { IntPtr ptr = source.GetHbitmap(); BitmapSource bs = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap( ptr, IntPtr.Zero, Int32Rect.Empty, System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions()); DeleteObject(ptr); return bs; } } }
测试：
Bitmap bm = (Bitmap)Bitmap.FromFile(@"D:\my_testfiles\Main.png"); int count = 10000000; for (int i = 0; i < count; i++) { Commons.BitMapToImageSource(bm.Clone() as Bitmap); }
结果：
当循环 1527次， 耗时 00:00:17.8860231后 报错。
ErrorTrace：
at System.Drawing.Bitmap.GetHbitmap(Color background) at System.Drawing.Bitmap.GetHbitmap() at SimpleClient.Commons.BitMapToImageSource(Bitmap bitmap) in D:\my_svn\universal-project\SimpleClient\Program.cs:line 165
ErrorMessage:
system.OutOfMemoryException: Out of memory.
改进：
写一个视频显示控件，内部实现显示Bitmap转换成BitmapSource。为控件Source开辟一块内存控件，然后一直刷新。首先我们使用EmuguCV里面的Capture。
控件继承Image、IDisposable接口并开放一个属性VideoSource。
代码如下：
public class CapPlayer : Image, IDisposable { private Capture videoSource; public Capture VideoSource { set { if (value != null) { this.videoSource = value; this.LaodCapPlayer(); } } } private InteropBitmap bitmapSource; private IntPtr map; private IntPtr section; public CapPlayer() { Application.Current.Exit += new ExitEventHandler(Current_Exit); } private void LaodCapPlayer() { videoSource.ImageGrabbed += new Capture.GrabEventHandler(videoSource_ImageGrabbed); videoSource.Start(); uint pcount = (uint)(videoSource.Width * videoSource.Height * PixelFormats.Bgr32.BitsPerPixel / 8); section = CreateFileMapping(new IntPtr(-1), IntPtr.Zero, 0x04, 0, pcount, null); map = MapViewOfFile(section, 0xF001F, 0, 0, pcount); bitmapSource = Imaging.CreateBitmapSourceFromMemorySection(section, (int)videoSource.Width, (int)videoSource.Height, PixelFormats.Bgr32, (int)(videoSource.Width * PixelFormats.Bgr32.BitsPerPixel / 8), 0) as InteropBitmap; this.Source = bitmapSource; } void videoSource_ImageGrabbed(object sender, EventArgs e) { Capture camera = sender as Capture; var frame = camera.RetrieveBgrFrame().Bitmap; if (this.Dispatcher != null) { this.Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.Render, (SendOrPostCallback)delegate { if (map != IntPtr.Zero) { try { System.Drawing.Imaging.BitmapData bmpData = frame.LockBits(new System.Drawing.Rectangle(0, 0, (int)videoSource.Width, (int)videoSource.Height), System.Drawing.Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppRgb); /* Get the pointer to the pixels */ IntPtr pBmp = bmpData.Scan0; int srcStride = bmpData.Stride; int pSize = srcStride * (int)videoSource.Height; CopyMemory(map, pBmp, pSize); frame.UnlockBits(bmpData); } catch (Exception ex) { Microsoft.Practices.EnterpriseLibrary.Logging.Logger.Write(ex, "Info", 0); } } if (bitmapSource != null) { bitmapSource.Invalidate(); } }, null); } if (captureLock) { try { lock (mutCurrentImg) { camera.RetrieveBgrFrame().Save(imageFileName); } } catch (System.Exception ex) { Microsoft.Practices.EnterpriseLibrary.Logging.Logger.Write(ex, "Info", 0); } captureLock = false; } } void Current_Exit(object sender, ExitEventArgs e) { this.Dispose(); } object mutCurrentImg = new object(); bool captureLock = false; string imageFileName = string.Empty; public void ImaggingCapture(string imageFileName) { this.imageFileName = imageFileName; this.captureLock = true; } #region IDisposable Members public void Dispose() { if (videoSource != null) videoSource.Stop(); Application.Current.Exit -= new ExitEventHandler(Current_Exit); } #endregion [DllImport("Kernel32.dll", EntryPoint = "RtlMoveMemory")] private static extern void CopyMemory(IntPtr Destination, IntPtr Source, int Length); [DllImport("kernel32.dll", SetLastError = true)] static extern IntPtr CreateFileMapping(IntPtr hFile, IntPtr lpFileMappingAttributes, uint flProtect, uint dwMaximumSizeHigh, uint dwMaximumSizeLow, string lpName); [DllImport("kernel32.dll", SetLastError = true)] static extern IntPtr MapViewOfFile(IntPtr hFileMappingObject, uint dwDesiredAccess, uint dwFileOffsetHigh, uint dwFileOffsetLow, uint dwNumberOfBytesToMap); }
测试结果：无异常，但是发现比较占用CPU 10%左右，内存 122M 左右，线程数32.
感觉不太理想CPU占用太多，我们把EmuguCV的Capture改为AForge.NEt的VideoCaptureDevice，代码如下：
public class CapPlayer : Image, IDisposable { private VideoCaptureDevice videoSource; private InteropBitmap bitmapSource; private IntPtr map; private IntPtr section; public CapPlayer() { Application.Current.Exit += new ExitEventHandler(Current_Exit); this.Loaded += new RoutedEventHandler(CapPlayer_Loaded); videoSource = new VideoCaptureDevice(@"device:pnp:\\?\usb#vid_0ac8&pid_305b#5&ee85354&0&2#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\global"); } void CapPlayer_Loaded(object sender, RoutedEventArgs e) { videoSource.NewFrame += new NewFrameEventHandler(videoSource_NewFrame); videoSource.Start(); uint pcount = (uint)(this.Width * this.Height * PixelFormats.Bgr32.BitsPerPixel / 8); section = CreateFileMapping(new IntPtr(-1), IntPtr.Zero, 0x04, 0, pcount, null); map = MapViewOfFile(section, 0xF001F, 0, 0, pcount); bitmapSource = System.Windows.Interop.Imaging.CreateBitmapSourceFromMemorySection(section, (int)this.Width, (int)this.Height, PixelFormats.Bgr32, (int)(this.Width * PixelFormats.Bgr32.BitsPerPixel / 8), 0) as InteropBitmap; this.Source = bitmapSource; } void Current_Exit(object sender, ExitEventArgs e) { this.Dispose(); } object mutCurrentImg = new object(); bool captureLock = false; string imageFileName = string.Empty; public void ImaggingCapture(string imageFileName) { this.imageFileName = imageFileName; this.captureLock = true; } private void videoSource_NewFrame(object sender, NewFrameEventArgs eventArgs) { //eventArgs.Frame.Save(stream, System.Drawing.Imaging.ImageFormat.Bmp); if (this.Dispatcher != null) { this.Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.Render, (SendOrPostCallback)delegate { if (map != IntPtr.Zero) { System.Drawing.Imaging.BitmapData bmpData = eventArgs.Frame.LockBits(new System.Drawing.Rectangle(0, 0, (int)this.Width, (int)this.Height), System.Drawing.Imaging.ImageLockMode.ReadWrite, System.Drawing.Imaging.PixelFormat.Format32bppRgb); /* Get the pointer to the pixels */ IntPtr pBmp = bmpData.Scan0; int srcStride = bmpData.Stride; int pSize = srcStride * (int)this.Height; CopyMemory(map, pBmp, pSize); eventArgs.Frame.UnlockBits(bmpData); } if (bitmapSource != null) { bitmapSource.Invalidate(); } }, null); } if (captureLock) { try { lock (mutCurrentImg) { eventArgs.Frame.Save(imageFileName); } } catch (System.Exception ex) { } captureLock = false; } } #region IDisposable Members public void Dispose() { if (videoSource != null) videoSource.SignalToStop(); } #endregion [DllImport("Kernel32.dll", EntryPoint = "RtlMoveMemory")] private static extern void CopyMemory(IntPtr Destination, IntPtr Source, int Length); [DllImport("kernel32.dll", SetLastError = true)] static extern IntPtr CreateFileMapping(IntPtr hFile, IntPtr lpFileMappingAttributes, uint flProtect, uint dwMaximumSizeHigh, uint dwMaximumSizeLow, string lpName); [DllImport("kernel32.dll", SetLastError = true)] static extern IntPtr MapViewOfFile(IntPtr hFileMappingObject, uint dwDesiredAccess, uint dwFileOffsetHigh, uint dwFileOffsetLow, uint dwNumberOfBytesToMap); }
测试结果：无异常，但是发现占用CPU 1%左右，内存 72M 左右，线程数28. 是不是比较理想呢！！
|
|
CPU |
内存 |
线程数 |
| EmuguCV |
10%左右 |
122M左右 |
32 |
| Aforge.Net |
1%左右 |
72M左右 |
28 |
我的电脑配置.
摄像头：FrameRate 30，Width 320 Height 240.
电脑型号 戴尔 Precision WorkStation T3400 Tower
操作系统 Windows 7 旗舰版 32位 SP1 ( DirectX 11 )
处理器 英特尔 酷睿2 双核 E8400 @ 3.00GHz
主板 戴尔 0HY553 (英特尔 X38/X48 Express 芯片组 - ICH9R)
内存 4 GB ( 海力士 DDR2 800MHz / 金士顿 DDR2 667MHz )
主硬盘 西数 WDC WD3200AAKS-75L9A0 ( 320 GB / 7200 转/分 )
显卡 Nvidia Quadro NVS 290 ( 256 MB / Nvidia )
显示器 戴尔 DELA04A DELL E170S ( 17.1 英寸 )
光驱 飞利浦-建兴 DVD-ROM DH-16D5S DVD光驱
声卡 Analog Devices AD1984 @ 英特尔 82801I(ICH9) 高保真音频
网卡 博通 BCM5754 NetXtreme Gigabit Ethernet / 戴尔
gdi32.dll
系统文件gdi32.dll是存放在Windows系统文件夹中的重要文件，通常情况下是在安装操作系统过程中自动创建的，对于系统正常运行来说至关重要。除非用户电脑被木马病毒、或是流氓软件篡改导致出现gdi32.dll丢失、缺失损坏等弹窗现象，否则不建议用户对该类文件（gdi32.dll）进行随意的修改。
gdi32.dll是Windows GDI图形用户界面相关程序，包含的函数用来绘制图像和显示文字。
