C#调用摄像头扫描二维码，生成二维码第二版

修复了在某些win7 64位电脑无法扫描二维码的BUG 在C#下通过DirectShow控制摄像头，实现快照后解码二维码。 在winXP及win7下测试通过。 希望此代码对使用C#开发摄像头和二维码应用的人有用。

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2015-01-05 14:39  QRCodeService\
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\
     文件         881  2015-01-05 14:40  QRCodeService\QRCodeService\QRCodeService.sln
     文件       20992  2015-01-07 19:35  QRCodeService\QRCodeService\QRCodeService.suo
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\bin\
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\bin\Debug\
     文件      303104  2010-02-21 14:12  QRCodeService\QRCodeService\QRCodeService\bin\Debug\DirectShowLib-2005.dll
     文件       20992  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\bin\Debug\QRCodeService.exe
     文件       44544  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\bin\Debug\QRCodeService.pdb
     文件       11600  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\bin\Debug\QRCodeService.vshost.exe
     文件         490  2010-03-17 22:39  QRCodeService\QRCodeService\QRCodeService\bin\Debug\QRCodeService.vshost.exe.manifest
     文件      430080  2014-04-02 03:44  QRCodeService\QRCodeService\QRCodeService\bin\Debug\zxing.dll
     文件       20992  2014-04-02 03:44  QRCodeService\QRCodeService\QRCodeService\bin\Debug\zxing.presentation.dll
     目录           0  2015-01-05 14:41  QRCodeService\QRCodeService\QRCodeService\bin\Release\
     文件       18762  2015-01-05 14:57  QRCodeService\QRCodeService\QRCodeService\Capture.cs
     文件        9209  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\MainForm.cs
     文件        8535  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\MainForm.Designer.cs
     文件        5817  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\MainForm.resx
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\obj\
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\obj\x86\
     目录           0  2015-01-05 14:39  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\
     文件        4440  2015-01-05 16:01  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\DesignTimeResolveAssemblyReferences.cache
     文件        6558  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\DesignTimeResolveAssemblyReferencesInput.cache
     文件         314  2015-01-05 16:32  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\GenerateResource.read.1.tlog
     文件         750  2015-01-05 16:32  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\GenerateResource.write.1.tlog
     文件         907  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\QRCodeService.csproj.FileListAbsolute.txt
     文件       20992  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\QRCodeService.exe
     文件         180  2015-01-05 16:32  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\QRCodeService.MainForm.resources
     文件       44544  2015-01-07 19:34  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\QRCodeService.pdb
     文件         180  2015-01-05 15:03  QRCodeService\QRCodeService\QRCodeService\obj\x86\Debug\QRCodeService.Properties.Resources.resources
............此处省略12个文件信息