C#摄像头实现拍照功能的简单代码示例

2009-11-20  来自：网上整理字体大小：【大中小】

·摘要：这里将介绍一个C#摄像头实现拍照功能的简单代码示例，代码虽然不短，但是基本上实现了相对应的功能，希望对大家有所帮助。

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C#摄像头实现拍照功能的简单代码示例

1.using System;

2.using System.Runtime.InteropServices;

3.using System.Drawing;

4.using System.Drawing.Imaging;

5.namespace Video

6.{

7.///

8./// 一个C#摄像头控制类

9.///

10.publicclass VideoWork

11.{

12.privateconstint WM_USER = 0x400;

13.privateconstint WS_CHILD = 0x40000000;

14.privateconstint WS_VISIBLE = 0x10000000;

15.privateconstint WM_CAP_START = WM_USER;

16.privateconstint WM_CAP_STOP = WM_CAP_START + 68;

17.privateconstint WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;

18.privateconstint WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;

19.privateconstint WM_CAP_SAVEDIB = WM_CAP_START + 25;

20.privateconstint WM_CAP_GRAB_FRAME = WM_CAP_START + 60;

21.privateconstint WM_CAP_SEQUENCE = WM_CAP_START + 62;

22.privateconstint WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;

23.privateconstint WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63;

24.privateconstint WM_CAP_SET_OVERLAY =WM_CAP_START+ 51;

25.privateconstint WM_CAP_SET_PREVIEW =WM_CAP_START+ 50;

26.privateconstint WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;

27.privateconstint WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;

28.privateconstint WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;

29.privateconstint WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;

30.privateconstint WM_CAP_SET_SCALE=WM_CAP_START+ 53;

31.privateconstint WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52;

32.private IntPtr hWndC;

33.privatebool bWorkStart = false;

34.private IntPtr mControlPtr;

35.privateint mWidth;

36.privateint mHeight;

37.privateint mLeft;

38.privateint mTop;

39.

40.///

41./// 初始化显示图像

42.///

43./// 控件的句柄

44./// 开始显示的左边距

45./// 开始显示的上边距

46./// 要显示的宽度

47./// 要显示的长度

48.public VideoWork(IntPtr handle, int left, int top, int width,int height)

49.{

50.mControlPtr = handle;

51.mWidth = width;

52.mHeight = height;

53.mLeft = left;

54.mTop = top;

55.}

56.[DllImport("avicap32.dll")]

57.privatestaticextern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);

58.[DllImport("avicap32.dll")]

59.privatestaticexternint capGetVideoFormat(IntPtr hWnd, IntPtr psVideoFormat, int wSize );

60.[DllImport("User32.dll")]

61.privatestaticexternbool SendMessage(IntPtr hWnd, int wMsg, int wParam, long lParam);

62.///

63./// 开始显示图像

64.///

65.publicvoid Start()

66.{

67.if (bWorkStart)

68.return;

69.bWorkStart = true;

70.byte[] lpszName = newbyte[100];

71.hWndC = capCreateCaptureWindowA(lpszName,WS_CHILD|WS_VISIBLE ,mLeft,mTop,mWidth,mHeight,mControlPtr,0);

72.if (hWndC.ToInt32() != 0)

73.{

74.SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);

75.SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);

76.SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);

77.SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);

78.SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);

79.SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);

80.SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);

81.SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);

82.//Global.log.Write("SendMessage");

83.}

84.return;

85.}

86.///

87./// 停止显示

88.///

89.publicvoid Stop()

90.{

91.SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);

92.bWorkStart = false;

93.}

94.///

95./// 抓图

96.///

97./// 要保存bmp文件的路径

98.publicvoid GrabImage(string path)

99.{

100.IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);

101.SendMessage(hWndC,WM_CAP_SAVEDIB,0,hBmp.ToInt64());

102.}

103.}

104.}

105.

106.//这是一个控制摄像头进行拍照的类，我每次使用GrabImage抓图都是225K的一张照片，我想请问如何才能让我

107.//抓到的图片小一些，我想控制在70K左右。不知怎么让拍照的像素变小？

108.

109.if(this.Request.QueryString["filename"]!=null)

110.{

111.//获取原图片

112.string filename=this.Request.QueryString["filename"];

113.Bitmap bmpOld=new Bitmap(this.Server.MapPath("p_w_picpaths/" + filename));

114.//计算缩小比例

115.double d1;

116.if(bmpOld.Height>bmpOld.Width)

117.d1=(double)(MaxLength/(double)bmpOld.Width);

118.else

119.d1=(double)(MaxLength/(double)bmpOld.Height);

120.//产生缩图

121.Bitmap bmpThumb=new Bitmap(bmpOld,(int)(bmpOld.Width*d1),(int)(bmpOld.Height*d1));

122.//清除缓冲

123.Response.Clear();

124.//生成图片

125.bmpThumb.Save(this.Response.OutputStream,ImageFormat.Jpeg);

126.Response.End();

127.//释放资源

128.bmpThumb.Dispose();

129.bmpOld.Dispose();

130.}

C#摄像头实现拍照功能的简单代码示例就介绍到这里。