C#获取摄像头拍照显示图像

之前有个需求,就是在web界面可以实现调用摄像头,用户把手机的个人二维码展示给摄像头,摄像头进行摄像识别用户。其实本质就是保存图像二维码,在进行二维码识别。下面来看看如何实现。.

1、初始化摄像头

/// <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);

2、开始显示图像

/// <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;

        }

3、停止显示

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

4、抓图

/// <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);
}

完整代码:

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Windows.Forms;

using System.Runtime.InteropServices;

using com.google.zxing.qrcode.decoder;
using com.google.zxing.client;
using com.google.zxing.common;

using System.Threading;

public partial class Decode : System.Web.UI.Page
{
   // public delegate void SaveImg(Pick Pick1);
    /// <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);
        }

    }


    protected void Page_Load(object sender, EventArgs e)
{
       
    }
    //void DoInit()
    //{
    //    System.Windows.Forms.Form frm = new Form();
    //    frm.Height = 300;
    //    frm.Width = 300;
    //    System.Windows.Forms.PictureBox Panel = new System.Windows.Forms.PictureBox();
    //    Panel.Height = 300;
    //    Panel.Width = 300;
    //    Panel.Visible = true;
    //    Panel.BackgroundImageLayout = ImageLayout.None;
    //    frm.Controls.Add(Panel);
    //    frm.TopMost = true;
    //    Pick p = new Pick(Panel.Handle, 0, 0, 300, 300);
    //    p.Start();
    //    frm.Show();
    //    p.Kinescope(Server.MapPath("img\\Decode2.avi"));
    //    p.GrabImage(Server.MapPath("img\\Decode1.bmp"));
    //    p.Stop();
    //    frm.Close();
    //    frm.Dispose();
    //}
  
    private void getQrcode()
{
        try
        {
           
            //ThreadStart worker = new ThreadStart(DoInit);
            //Thread th = new Thread(worker);
            //th.IsBackground = true;
            //th.Start();
            System.Windows.Forms.Form frm = new Form();
            frm.Height = 300;
            frm.Width = 300;
            System.Windows.Forms.PictureBox Panel = new System.Windows.Forms.PictureBox();
            Panel.Height = 300;
            Panel.Width = 300;
            Panel.Visible = true;
            Panel.BackgroundImageLayout = ImageLayout.None;
            frm.Controls.Add(Panel);
            frm.TopMost = true;
            Pick p = new Pick(Panel.Handle, 0, 0, 300, 300);
            p.Start();
            int i = 1;
            while (i <= 1)
            {
                p.GrabImage(Server.MapPath("img\\Decode.bmp"));
                p.Kinescope(Server.MapPath("img\\Video.avi"));
                i++;
            }
            p.Stop();
            frm.Close();
            frm.Dispose();
            try
            {
                com.google.zxing.qrcode.QRCodeReader d = new com.google.zxing.qrcode.QRCodeReader();
                RGBLuminanceSource rg = new RGBLuminanceSource(new System.Drawing.Bitmap(Server.MapPath("img\\Decode.bmp")), new System.Drawing.Bitmap(Server.MapPath("img\\Decode.bmp")).Width, new System.Drawing.Bitmap(Server.MapPath("img\\Decode.bmp")).Height);
                com.google.zxing.LuminanceSource ls = rg;
                HybridBinarizer hb = new HybridBinarizer(ls);
                com.google.zxing.BinaryBitmap bm = new com.google.zxing.BinaryBitmap(hb);
                com.google.zxing.Result r = d.decode(bm);
                TextBox1.Text = r.Text;
     

            }
            catch (Exception ex)
            {

                TextBox1.Text = "";
                //MessageBox.Show(ex.Message+"111");

                throw new Exception(ex.Message);
            }
        }
        catch (Exception ee)
        {
            ee.ToString();
        }
    }
    protected void Timer1_Tick(object sender, EventArgs e)
{
        //getQrcode();
    }
    protected void Button1_Click(object sender, EventArgs e)
{
        getQrcode();
    }
}