C#获取摄像头拍照显示图像
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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();
}
}
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