摄像头编程WindowsAPI - avicap32.dll 参数详解

// 窗口消息 WM_CAP... 哪个是送到 AVICAP 窗口
// ------------------------------------------------------------------
// 开始定义消息参数 整数型
const avicap32='avicap32.dll';
WM_CAP_START= WM_USER=1024;
// start of unicode messages
WM_CAP_UNICODE_START=            WM_USER+100; //开始
WM_CAP_GET_CAPSTREAMPTR=         (WM_CAP_START+ 1); //获得 CAPSTR EAMPTR
WM_CAP_SET_CALLBACK_ERROR=       (WM_CAP_START+ 2); //设置回调错误
WM_CAP_SET_CALLBACK_STATUS=      (WM_CAP_START+ 3); //设置回调状态
WM_CAP_SET_CALLBACK_YIELD=       (WM_CAP_START+ 4); //设置回调出产
WM_CAP_SET_CALLBACK_FRAME=       (WM_CAP_START+ 5); //设置回调结构
WM_CAP_SET_CALLBACK_VIDEOSTREAM= (WM_CAP_START+ 6); //设置回调视频流
WM_CAP_SET_CALLBACK_WAVESTREAM= (WM_CAP_START+ 7); //设置回调视频波流
WM_CAP_GET_USER_DATA            =(WM_CAP_START+ 8); //获得使用者数据
WM_CAP_SET_USER_DATA           =(WM_CAP_START+ 9) ; //设置使用者数据
WM_CAP_DRIVER_CONNECT          =(WM_CAP_START+ 10); //驱动程序连接
WM_CAP_DRIVER_DISCONNECT       =(WM_CAP_START+ 11); //断开启动程序连接
WM_CAP_DRIVER_GET_NAME         =(WM_CAP_START+ 12); //获得驱动程序名字
WM_CAP_DRIVER_GET_VERSION      =(WM_CAP_START+ 13); //获得驱动程序版本
WM_CAP_DRIVER_GET_CAPS         =(WM_CAP_START+ 14); //获得驱动程序性能
WM_CAP_FILE_SET_CAPTURE_FILE    =(WM_CAP_START+ 20); //设置捕获文件的文件名
WM_CAP_FILE_GET_CAPTURE_FILE    =(WM_CAP_START+ 21); //获得捕获文件的文件名
WM_CAP_FILE_SAVEAS              =(WM_CAP_START+ 23); //另存文件为
WM_CAP_FILE_SAVEDIB             =(WM_CAP_START+ 25); //保存文件
// out of order to save on ifdefs
WM_CAP_FILE_ALLOCATE           =(WM_CAP_START+ 22); //分派文件, 为捕获文件建一个指定大小的文件
WM_CAP_FILE_SET_INFOCHUNK      =(WM_CAP_START+ 24); //设置开始文件
WM_CAP_EDIT_COPY               =(WM_CAP_START+ 30); //编辑复制,把图象考入剪贴板
WM_CAP_SET_AUDIOFORMAT         =(WM_CAP_START+ 35); //设置音频格式
WM_CAP_GET_AUDIOFORMAT         =(WM_CAP_START+ 36); //捕获音频格式
WM_CAP_DLG_VIDEOFORMAT         =(WM_CAP_START+ 41); //1065 打开视频格式设置对话框, 选择数字视频的框架大小和视频图像的色深，以及捕获视频图像的压缩格式。
WM_CAP_DLG_VIDEOSOURCE         =(WM_CAP_START+ 42); //1066 打开属性设置对话框，设置对比度、亮度等。(视频源对话框) 选择视频输入通道和视频图像的动态参数。
WM_CAP_DLG_VIDEODISPLAY        =(WM_CAP_START+ 43); //1067 打开视频显示对话框
WM_CAP_GET_VIDEOFORMAT         =(WM_CAP_START+ 44); //1068 获得视频格式
WM_CAP_SET_VIDEOFORMAT         =(WM_CAP_START+ 45); //1069 设置视频格式
WM_CAP_DLG_VIDEOCOMPRESSION    =(WM_CAP_START+ 46); //1070 打开压缩设置对话框
WM_CAP_SET_PREVIEW             =(WM_CAP_START+ 50); //设置预览模式
WM_CAP_SET_OVERLAY             =(WM_CAP_START+ 51); //设置覆盖
WM_CAP_SET_PREVIEWRATE         =(WM_CAP_START+ 52); //设置预览模式下图像的帧速度
WM_CAP_SET_SCALE               =(WM_CAP_START+ 53); //设置预览视频的缩放比例
WM_CAP_GET_STATUS              =(WM_CAP_START+ 54); //获得状态
WM_CAP_SET_SCROLL              =(WM_CAP_START+ 55); //设置卷
WM_CAP_GRAB_FRame              =(WM_CAP_START+ 60); //逮捕结构
WM_CAP_GRAB_FRame_NOSTOP       =(WM_CAP_START+ 61); //停止逮捕结构,截取当前图象
WM_CAP_SEQUENCE                =(WM_CAP_START+ 62); //次序，捕捉到文件
WM_CAP_SEQUENCE_NOFILE         =(WM_CAP_START+ 63); //没有文件
WM_CAP_SET_SEQUENCE_SETUP      =(WM_CAP_START+ 64); //设置当前捕获的帧频率
WM_CAP_GET_SEQUENCE_SETUP      =(WM_CAP_START+ 65); //获得当前捕获的帧频率
WM_CAP_SET_MCI_DEVICE          =(WM_CAP_START+ 66); //设置媒体控制接口
WM_CAP_GET_MCI_DEVICE          =(WM_CAP_START+ 67); //获得媒体控制接口
WM_CAP_STOP                    =(WM_CAP_START+ 68); //停止捕捉
WM_CAP_ABORT                   =(WM_CAP_START+ 69); //异常中断
WM_CAP_SINGLE_FRame_OPEN       =(WM_CAP_START+ 70); //打开单一的结构
WM_CAP_SINGLE_FRame_CLOSE      =(WM_CAP_START+ 71); //关闭单一的结构
WM_CAP_SINGLE_FRame            =(WM_CAP_START+ 72); //单一的结构
WM_CAP_PAL_OPEN                =(WM_CAP_START+ 80); //打开视频
WM_CAP_PAL_SAVE                =(WM_CAP_START+ 81); //保存视频
WM_CAP_PAL_PASTE               =(WM_CAP_START+ 82); //粘贴视频
WM_CAP_PAL_AUTOCREATE          =(WM_CAP_START+ 83); //自动创造
WM_CAP_PAL_MANUALCREATE        =(WM_CAP_START+ 84); //手动创造
// Following added post VFW 1.1
WM_CAP_SET_CALLBACK_CAPCONTROL =(WM_CAP_START+ 85); // 设置收回的错误
WM_CAP_END                      =WM_CAP_SET_CALLBACK_CAPCONTROL;

 using System;
　　using System.Runtime.InteropServices;
　　using System.Drawing;
　　using System.Drawing.Imaging;

　　namespace PickHead
　　{
　　/// <summary>
　　/// 一个控制摄像头的类
　　/// </summary>
　　public class Pick
　　{
　　private const int WM_USER = 0x400;
　　private const int WS_CHILD = 0x40000000;
　　private const int WS_VISIBLE = 0x10000000;
　　private const int WM_CAP_START = WM_USER;
　　private const int WM_CAP_STOP = WM_CAP_START + 68;
　　private const int WM_CAP_DRIVER_CONNECT = WM_CAP_START + 10;
　　private const int WM_CAP_DRIVER_DISCONNECT = WM_CAP_START + 11;
　　private const int WM_CAP_SAVEDIB = WM_CAP_START + 25;
　　private const int WM_CAP_GRAB_FRAME = WM_CAP_START + 60;
　　private const int WM_CAP_SEQUENCE = WM_CAP_START + 62;
　　private const int WM_CAP_FILE_SET_CAPTURE_FILEA = WM_CAP_START + 20;
　　private const int WM_CAP_SEQUENCE_NOFILE =WM_CAP_START+ 63;
　　private const int WM_CAP_SET_OVERLAY =WM_CAP_START+ 51; 
　　private const int WM_CAP_SET_PREVIEW =WM_CAP_START+ 50; 
　　private const int WM_CAP_SET_CALLBACK_VIDEOSTREAM = WM_CAP_START +6;
　　private const int WM_CAP_SET_CALLBACK_ERROR=WM_CAP_START +2;
　　private const int WM_CAP_SET_CALLBACK_STATUSA= WM_CAP_START +3;
　　private const int WM_CAP_SET_CALLBACK_FRAME= WM_CAP_START +5;
　　private const int WM_CAP_SET_SCALE=WM_CAP_START+ 53;
　　private const int WM_CAP_SET_PREVIEWRATE=WM_CAP_START+ 52; 
　　private IntPtr hWndC;
　　private bool bStat = false;
　　
　　private IntPtr mControlPtr;
　　private int mWidth;
　　private int mHeight;
　　private int mLeft;
　　private int mTop;
　　
　　/// <summary>
　　/// 初始化摄像头
　　/// </summary>
　　/// <param name="handle">控件的句柄</param>
　　/// <param name="left">开始显示的左边距</param>
　　/// <param name="top">开始显示的上边距</param>
　　/// <param name="width">要显示的宽度</param>
　　/// <param name="height">要显示的长度</param>
　　public Pick(IntPtr handle, int left, int top, int width,int height)
　　{
　　mControlPtr = handle;
　　mWidth = width;
　　mHeight = height;
　　mLeft = left;
　　mTop = top;
　　}

　　[DllImport("avicap32.dll")] 
　　private static extern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);
　　
　　[DllImport("avicap32.dll")]
　　private static extern int capGetVideoFormat(IntPtr hWnd, IntPtr psVideoFormat, int wSize );
　　[DllImport("User32.dll")] 
　　private static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, long lParam);

　　/// <summary>
　　/// 开始显示图像
　　/// </summary>
　　public void Start()
　　{
　　if (bStat)
　　return;
　　
　　bStat = true;
　　byte[] lpszName = new byte[100];
　　
　　hWndC = capCreateCaptureWindowA(lpszName,WS_CHILD|WS_VISIBLE ,mLeft,mTop,mWidth,mHeight,mControlPtr,0);

　　if (hWndC.ToInt32() != 0)
　　{
　　SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
　　SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
　　SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
　　SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
　　SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
　　SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
　　SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
　　SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
　　}

　　return;

　　}

　　/// <summary>
　　/// 停止显示

　　/// </summary>
　　public void Stop()
　　{
　　SendMessage(hWndC, WM_CAP_DRIVER_DISCONNECT, 0, 0);
　　bStat = false;
　　}

　　/// <summary>
　　/// 抓图
　　/// </summary>
　　/// <param name="path">要保存bmp文件的路径</param>
　　public void GrabImage(string path)
　　{
　　
　　IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
　　SendMessage(hWndC,WM_CAP_SAVEDIB,0,hBmp.ToInt64());

　　}

　　/// <summary>
　　/// 录像
　　/// </summary>
　　/// <param name="path">要保存avi文件的路径</param>
　　public void Kinescope(string path)
　　{
　　IntPtr hBmp = Marshal.StringToHGlobalAnsi(path);
　　SendMessage(hWndC,WM_CAP_FILE_SET_CAPTURE_FILEA,0,hBmp.ToInt64());
　　SendMessage(hWndC, WM_CAP_SEQUENCE, 0, 0);
　　}

　　/// <summary>
　　/// 停止录像
　　/// </summary>
　　public void StopKinescope()
　　{
　　SendMessage(hWndC, WM_CAP_STOP, 0, 0);
　　}

　　}
　　}