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hi everyone,
I'm using C# and direcX library to capture video from a webcam.

i managed to capture video with a great quality in .avi format(which the format is set by the library, i didn't make it).

but here is the problem each minute of captured video is approximately 1.0 GB of harddisk space!!!
So i used its compressor method which was mentioned in directX help file.
BUT, now it makes the file MUCH smaller but 2 real annoying problems are there NOW:

1. when it's capturing the preview is SO MUCH slow!
2. the captured file is not smooth any more and leaks alot!

please help me.... I'm confused SO MUCH
Posted
Comments
Debojyoti Majumder 21-Mar-11 1:37am    
Can you share your code??

Can i capture video through website application
 
Share this answer
 
private void openMJEPGFileItem_Click( object sender, System.EventArgs e )
{
URLForm form = new URLForm( );

form.Description = "Enter URL of an MJPEG video stream:";
form.URLs = new string[]
{
"http://129.186.47.239/axis-cgi/mjpg/video.cgi?resolution=352x240",
"http://195.243.185.195/axis-cgi/mjpg/video.cgi?camera=3",
"http://195.243.185.195/axis-cgi/mjpg/video.cgi?camera=4",
"http://chipmunk.uvm.edu/cgi-bin/webcam/nph-update.cgi?dummy=garb"
};

if ( form.ShowDialog( this ) == DialogResult.OK )
{
// create video source
MJPEGStream mjpegSource = new MJPEGStream( );
mjpegSource.VideoSource = form.URL;

// open it
OpenVideoSource( mjpegSource );
}
}

--------------------------------------------------------------------------------------------------------------------
namespace VideoSource
{
using System;
using System.Drawing;
using System.IO;
using System.Text;
using System.Threading;
using System.Net;

/// <summary>
/// MJPEGSource - MJPEG stream support
/// </summary>
public class MJPEGStream : IVideoSource
{
private string source;
private string login = null;
private string password = null;
private object userData = null;
private int framesReceived;
private int bytesReceived;
private bool useSeparateConnectionGroup = true;

private const int bufSize = 512 * 1024; // buffer size
private const int readSize = 1024; // portion size to read

private Thread thread = null;
private ManualResetEvent stopEvent = null;
private ManualResetEvent reloadEvent = null;

// new frame event
public event CameraEventHandler NewFrame;

// SeparateConnectioGroup property
// indicates to open WebRequest in separate connection group
public bool SeparateConnectionGroup
{
get { return useSeparateConnectionGroup; }
set { useSeparateConnectionGroup = value; }
}
// VideoSource property
public string VideoSource
{
get { return source; }
set
{
source = value;
// signal to reload
if (thread != null)
reloadEvent.Set();
}
}
// Login property
public string Login
{
get { return login; }
set { login = value; }
}
// Password property
public string Password
{
get { return password; }
set { password = value; }
}
// FramesReceived property
public int FramesReceived
{
get
{
int frames = framesReceived;
framesReceived = 0;
return frames;
}
}
// BytesReceived property
public int BytesReceived
{
get
{
int bytes = bytesReceived;
bytesReceived = 0;
return bytes;
}
}
// 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 MJPEGStream()
{
}

// Start work
public void Start()
{
if (thread == null)
{
framesReceived = 0;
bytesReceived = 0;

// create events
stopEvent = new ManualResetEvent(false);
reloadEvent = 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;
reloadEvent.Close();
reloadEvent = null;
}

// Thread entry point
public void WorkerThread()
{
byte[] buffer = new byte[bufSize]; // buffer to read stream

while (true)
{
// reset reload event
reloadEvent.Reset();

HttpWebRequest req = null;
WebResponse resp = null;
Stream stream = null;
byte[] delimiter = null;
byte[] delimiter2 = null;
byte[] boundary = null;
int boundaryLen, delimiterLen = 0, delimiter2Len = 0;
int read, todo = 0, total = 0, pos = 0, align = 1;
int start = 0, stop = 0;

// align
// 1 = searching for image start
// 2 = searching for image end
try
{
// create request
req = (HttpWebRequest) WebRequest.Create(source);
// set login and password
if ((login != null) && (password != null) && (login != ""))
req.Credentials = new NetworkCredential(login, password);
// set connection group name
if (useSeparateConnectionGroup)
req.ConnectionGroupName = GetHashCode().ToString();
// get response
resp = req.GetResponse();

// check content type
string ct = resp.ContentType;
if (ct.IndexOf("multipart/x-mixed-replace") == -1)
throw new ApplicationException("Invalid URL");

// get boundary
ASCIIEncoding encoding = new ASCIIEncoding();
boundary = encoding.GetBytes(ct.Substring(ct.IndexOf("boundary=", 0) + 9));
boundaryLen = boundary.Length;

// get response stream
stream = resp.GetResponseStream();

// loop
while ((!stopEvent.WaitOne(0, true)) && (!reloadEvent.WaitOne(0, true)))
{
// check total read
if (total > bufSize - readSize)
{
System.Diagnostics.Debug.WriteLine("flushing");
total = pos = todo = 0;
}

// read next portion from stream
if ((read = stream.Read(buffer, total, readSize)) == 0)
throw new ApplicationException();

total += read;
todo += read;

// increment received bytes counter
bytesReceived += read;

// does we know the delimiter ?
if (delimiter == null)
{
// find boundary
pos = ByteArrayUtils.Find(buffer, boundary, pos, todo);

if (pos == -1)
{
// was not found
todo = boundaryLen - 1;
pos = total - todo;
continue;
}

todo = total - pos;

if (todo < 2)
continue;

// check new line delimiter type
if (buffer[pos + boundaryLen] == 10)
{
delimiterLen = 2;
delimiter = new byte[2] {10, 10};
delimiter2Len = 1;
delimiter2 = new byte[1] {10};
}
else
{
delimiterLen = 4;
delimiter = new byte[4] {13, 10, 13, 10};
delimiter2Len = 2;
delimiter2 = new byte[2] {13, 10};
}

pos += boundaryLen + delimiter2Len;
todo = total - pos;
}

// boundary aligned
/* if ((align == 0) && (todo >= boundaryLen))
{
if (ByteArrayUtils.Compare(buffer, boundary, pos))
{
// boundary located
align = 1;
todo -= boundaryLen;
pos += boundaryLen;
}
else
align = 2;
}*/

// search for image
if (align == 1)
{
start = ByteArrayUtils.Find(buffer, delimiter, pos, todo);
if (start != -1)
{
// found delimiter
start += delimiterLen;
pos = start;
todo = total - pos;
align = 2;
}
else
{
// delimiter not found
todo = delimiterLen - 1;
pos = total - todo;
}
}

// search for image end
while ((align == 2) && (todo >= boundaryLen))
{
stop = ByteArrayUtils.Find(buffer, boundary, pos, todo);
if (stop != -1)
{
pos = stop;
todo = total - pos;

// increment frames counter
framesReceived ++;

// image at stop
if (NewFrame != null)
{
Bitmap bmp = (Bitmap) Bitmap.FromStream(new MemoryStream(buffer, start, stop - start));
// notify client
NewFrame(this, new CameraEventArgs(bmp));
// release the image
bmp.Dispose();
bmp = null;
}
// System.Diagnostics.Debug.WriteLine("found image end, size = " + (stop - start));

// shift array
pos = stop + boundaryLen;
todo = total - pos;
Array.Copy(buffer, pos, buffer, 0, todo);

total = todo;
pos = 0;
align = 1;
}
else
{
// delimiter not found
todo = boundaryLen - 1;
pos = total - todo;
}
}
}
}
catch (WebException ex)
{
System.Diagnostics.Debug.WriteLine("=============: " + ex.Message);
// wait for a while before the next try
Thread.Sleep(250);
}
catch (ApplicationException ex)
{
System.Diagnostics.Debug.WriteLine("=============: " + ex.Message);
// wait for a while before the next try
Thread.Sleep(250);
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine("=============: " + ex.Message);
}
finally
{
// abort request
if (req != null)
{
req.Abort();
req = null;
}
// close response stream
if (stream != null)
{
stream.Close();
stream = null;
}
// close response
if (resp != null)
{
resp.Close();
resp = null;
}
}

// need to stop ?
if (stopEvent.WaitOne(0, true))
break;
}
}
}
}


----------------------------------------------------------------------------------------------------------------------

for smoothing the video you can use dshow
^]
 
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