www.pudn.com > motion_src.zip > CaptureDevice.cs
namespace videosource
{
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Threading;
using System.Runtime.InteropServices;
using System.Net;
using dshow;
using dshow.Core;
///
/// CaptureDevice - capture video from local device
///
public class CaptureDevice : IVideoSource
{
private string source;
private object userData = null;
private int framesReceived;
private Thread thread = null;
private ManualResetEvent stopEvent = null;
// new frame event
public event CameraEventHandler NewFrame;
// VideoSource property
public virtual string VideoSource
{
get { return source; }
set { source = value; }
}
// Login property
public string Login
{
get { return null; }
set { }
}
// Password property
public string Password
{
get { return null; }
set { }
}
// FramesReceived property
public int FramesReceived
{
get
{
int frames = framesReceived;
framesReceived = 0;
return frames;
}
}
// BytesReceived property
public int BytesReceived
{
get { return 0; }
}
// UserData property
public object UserData
{
get { return userData; }
set { userData = value; }
}
// Get state of the video source thread
public bool Running
{
get
{
if (thread != null)
{
if (thread.Join(0) == false)
return true;
// the thread is not running, so free resources
Free();
}
return false;
}
}
// Constructor
public CaptureDevice()
{
}
// Start work
public void Start()
{
if (thread == null)
{
framesReceived = 0;
// create events
stopEvent = new ManualResetEvent(false);
// create and start new thread
thread = new Thread(new ThreadStart(WorkerThread));
thread.Name = source;
thread.Start();
}
}
// Signal thread to stop work
public void SignalToStop()
{
// stop thread
if (thread != null)
{
// signal to stop
stopEvent.Set();
}
}
// Wait for thread stop
public void WaitForStop()
{
if (thread != null)
{
// wait for thread stop
thread.Join();
Free();
}
}
// Abort thread
public void Stop()
{
if (this.Running)
{
thread.Abort();
// WaitForStop();
}
}
// Free resources
private void Free()
{
thread = null;
// release events
stopEvent.Close();
stopEvent = null;
}
// Thread entry point
public void WorkerThread()
{
// grabber
Grabber grabber = new Grabber(this);
// objects
object graphObj = null;
object sourceObj = null;
object grabberObj = null;
// interfaces
IGraphBuilder graph = null;
IBaseFilter sourceBase = null;
IBaseFilter grabberBase = null;
ISampleGrabber sg = null;
IMediaControl mc = null;
try
{
// Get type for filter graph
Type srvType = Type.GetTypeFromCLSID(Clsid.FilterGraph);
if (srvType == null)
throw new ApplicationException("Failed creating filter graph");
// create filter graph
graphObj = Activator.CreateInstance(srvType);
graph = (IGraphBuilder) graphObj;
// ----
UCOMIBindCtx bindCtx = null;
UCOMIMoniker moniker = null;
int n = 0;
// create bind context
if (Win32.CreateBindCtx(0, out bindCtx) == 0)
{
// convert moniker`s string to a moniker
if (Win32.MkParseDisplayName(bindCtx, source, ref n, out moniker) == 0)
{
// get device base filter
Guid filterId = typeof(IBaseFilter).GUID;
moniker.BindToObject(null, null, ref filterId, out sourceObj);
Marshal.ReleaseComObject(moniker);
moniker = null;
}
Marshal.ReleaseComObject(bindCtx);
bindCtx = null;
}
// ----
if (sourceObj == null)
throw new ApplicationException("Failed creating device object for moniker");
sourceBase = (IBaseFilter) sourceObj ;
// Get type for sample grabber
srvType = Type.GetTypeFromCLSID(Clsid.SampleGrabber);
if (srvType == null)
throw new ApplicationException("Failed creating sample grabber");
// create sample grabber
grabberObj = Activator.CreateInstance(srvType);
sg = (ISampleGrabber) grabberObj;
grabberBase = (IBaseFilter) grabberObj;
// add source filter to graph
graph.AddFilter(sourceBase, "source");
graph.AddFilter(grabberBase, "grabber");
// set media type
AMMediaType mt = new AMMediaType();
mt.majorType = MediaType.Video;
mt.subType = MediaSubType.RGB24;
sg.SetMediaType(mt);
// connect pins
if (graph.Connect(DSTools.GetOutPin(sourceBase, 0), DSTools.GetInPin(grabberBase, 0)) < 0)
throw new ApplicationException("Failed connecting filters");
// get media type
if (sg.GetConnectedMediaType(mt) == 0)
{
VideoInfoHeader vih = (VideoInfoHeader) Marshal.PtrToStructure(mt.formatPtr, typeof(VideoInfoHeader));
System.Diagnostics.Debug.WriteLine("width = " + vih.BmiHeader.Width + ", height = " + vih.BmiHeader.Height);
grabber.Width = vih.BmiHeader.Width;
grabber.Height = vih.BmiHeader.Height;
mt.Dispose();
}
// render
graph.Render(DSTools.GetOutPin(grabberBase, 0));
//
sg.SetBufferSamples(false);
sg.SetOneShot(false);
sg.SetCallback(grabber, 1);
// window
IVideoWindow win = (IVideoWindow) graphObj;
win.put_AutoShow(false);
win = null;
// get media control
mc = (IMediaControl) graphObj;
// run
mc.Run();
while (!stopEvent.WaitOne(0, true))
{
Thread.Sleep(100);
}
mc.StopWhenReady();
}
// catch any exceptions
catch (Exception e)
{
System.Diagnostics.Debug.WriteLine("----: " + e.Message);
}
// finalization block
finally
{
// release all objects
mc = null;
graph = null;
sourceBase = null;
grabberBase = null;
sg = null;
if (graphObj != null)
{
Marshal.ReleaseComObject(graphObj);
graphObj = null;
}
if (sourceObj != null)
{
Marshal.ReleaseComObject(sourceObj);
sourceObj = null;
}
if (grabberObj != null)
{
Marshal.ReleaseComObject(grabberObj);
grabberObj = null;
}
}
}
// new frame
protected void OnNewFrame(Bitmap image)
{
framesReceived++;
if ((!stopEvent.WaitOne(0, true)) && (NewFrame != null))
NewFrame(this, new CameraEventArgs(image));
}
// Grabber
private class Grabber : ISampleGrabberCB
{
private CaptureDevice parent;
private int width, height;
// Width property
public int Width
{
get { return width; }
set { width = value; }
}
// Height property
public int Height
{
get { return height; }
set { height = value; }
}
// Constructor
public Grabber(CaptureDevice parent)
{
this.parent = parent;
}
//
public int SampleCB(double SampleTime, IntPtr pSample)
{
return 0;
}
// Callback method that receives a pointer to the sample buffer
public int BufferCB(double SampleTime, IntPtr pBuffer, int BufferLen)
{
// create new image
System.Drawing.Bitmap img = new Bitmap(width, height, PixelFormat.Format24bppRgb);
// lock bitmap data
BitmapData bmData = img.LockBits(
new Rectangle(0, 0, width, height),
ImageLockMode.ReadWrite,
PixelFormat.Format24bppRgb);
// copy image data
int srcStride = bmData.Stride;
int dstStride = bmData.Stride;
int dst = bmData.Scan0.ToInt32() + dstStride * (height - 1);
int src = pBuffer.ToInt32();
for (int y = 0; y < height; y++)
{
Win32.memcpy(dst, src, srcStride);
dst -= dstStride;
src += srcStride;
}
// unlock bitmap data
img.UnlockBits(bmData);
// notify parent
parent.OnNewFrame(img);
// release the image
img.Dispose();
return 0;
}
}
}
}