C#获取摄像头拍照显示图像

左手的ㄟ右手 2022-08-28 04:41 248阅读 0赞

## 概述 ##

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。

## 主要代码实现 ##

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();
        }
    
    }