Why im getting access denied exception ?

[EDN Admin]

In Form1 im doing:

private void timer1_Tick(object sender, EventArgs e)
{
Image mScreenImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width,
Screen.PrimaryScreen.Bounds.Height);
ffmp.PushFrame((Bitmap)mScreenImage);
mScreenImage.Dispose();
}



Im pusing the same frame for testing every 40ms .

Now in the ffmpeg class i did:

using System;
using System.Windows.Forms;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Drawing;
using System.IO.Pipes;
using System.Runtime.InteropServices;
using System.Diagnostics;
using System.IO;
using DannyGeneral;

namespace ScreenVideoRecorder
{
class Ffmpeg
{
NamedPipeServerStream p;
String pipename = "mytestpipe";
byte[] b;
System.Diagnostics.Process process;
string ffmpegFileName = "ffmpeg.exe";
string workingDirectory;

public Ffmpeg()
{
workingDirectory = Path.GetDirectoryName(Application.ExecutablePath);
Logger.Write("workingDirectory: " + workingDirectory);
if (!Directory.Exists(workingDirectory))
{
Directory.CreateDirectory(workingDirectory);
}
ffmpegFileName = Path.Combine(workingDirectory, ffmpegFileName);
Logger.Write("FfmpegFilename: " + ffmpegFileName);
}

public void Start(string pathFileName, int BitmapRate)
{
RunProcessLargeFile(@"-f rawvideo -pix_fmt bgr0 -video_size 1920x1080 -i \.pipemytestpipe -map 0 -c:v libx264 -r " + BitmapRate + " " + pathFileName);
p.WaitForConnection();
}

public void PushFrame(Bitmap bmp)
{
try
{
int length;
// Lock the bitmaps bits.
//bmp = new Bitmap(1920, 1080);
Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
//Rectangle rect = new Rectangle(0, 0, 1280, 720);
System.Drawing.Imaging.BitmapData bmpData =
bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly,
bmp.PixelFormat);

int absStride = Math.Abs(bmpData.Stride);
// Get the address of the first line.
IntPtr ptr = bmpData.Scan0;

// Declare an array to hold the bytes of the bitmap.
//length = 3 * bmp.Width * bmp.Height;
length = absStride * bmpData.Height;
byte[] rgbValues = new byte[length];

//Marshal.Copy(ptr, rgbValues, 0, length);
int j = bmp.Height - 1;
for (int i = 0; i < bmp.Height; i++)
{
IntPtr pointer = new IntPtr(bmpData.Scan0.ToInt32() + (bmpData.Stride * j));
System.Runtime.InteropServices.Marshal.Copy(pointer, rgbValues, absStride * (bmp.Height - i - 1), absStride);
j--;
}
p.Write(rgbValues, 0, length);
bmp.UnlockBits(bmpData);
}
catch(Exception err)
{
Logger.Write("Error: " + err.ToString());
}
/*for (j = 0; j < 25 * 10; j++) // put about 10 seconds of frames ( assumes 25 frames per second)
{

// put some data as rgb.. (rgb24bpp = 3 bytes per pixel)
for (i = 0; i < b.Length; i++)
{
if (((i) % 3) == 0)
b = (byte)(i + j);
else
b = 0;
}


p.Write(b, 0, b.Length); // send this rgb data to the pipe (ffmpeg.exe will read it..)
}*/
}

public void Close()
{
p.Close();
process.CloseMainWindow();
}

private string RunProcessLargeFile(string Parameters)
{
/* The below will be the right solution ....
* The while loop which reads the stream is very improtant
* for FFMPEG as .NET does not provide more memory to FFMPEG.
* When converting large files, FFMPEGs out put stream gets filled...
* And waits for .NET to allocate memory resources but is never done.
* In order to utilize less memory, we are clearing the buffer periodically.
**/

ProcessStartInfo oInfo = new ProcessStartInfo(workingDirectory, Parameters);
oInfo.WorkingDirectory = Path.GetDirectoryName(workingDirectory);
oInfo.UseShellExecute = false;
oInfo.CreateNoWindow = true;
oInfo.RedirectStandardOutput = true;
oInfo.RedirectStandardError = true;
using (Process proc = System.Diagnostics.Process.Start(oInfo))
{
using (StreamReader srOutput = proc.StandardError)
{
System.Text.StringBuilder output = new System.Text.StringBuilder();

using (StreamReader objStreamReader = proc.StandardError)
{
System.Text.StringBuilder sbOutPut = new StringBuilder();

while (!proc.WaitForExit(1000))
{
sbOutPut.Append(objStreamReader.ReadToEnd().ToString());
}

if (proc.ExitCode == 0)
{
proc.Close();
if (objStreamReader != null)
{
objStreamReader.Close();
}
}
else
{
proc.Close();
if (objStreamReader != null)
{
objStreamReader.Close();
}
}
return sbOutPut.ToString();
}
}
}

}
}
}



The exception is on the line:

using (Process proc = System.Diagnostics.Process.Start(oInfo))


The full exception message :

System.ComponentModel.Win32Exception was unhandled
HResult=-2147467259
Message=Access is denied
Source=System
ErrorCode=-2147467259
NativeErrorCode=5
StackTrace:
at System.Diagnostics.Process.StartWithCreateProcess(ProcessStartInfo startInfo)
at System.Diagnostics.Process.Start()
at System.Diagnostics.Process.Start(ProcessStartInfo startInfo)
at ScreenVideoRecorder.Ffmpeg.RunProcessLargeFile(String Parameters) in d:C-SharpScreenVideoRecorderScreenVideoRecorderWorkingVersionFfmpeg.cs:line 146
at ScreenVideoRecorder.Ffmpeg.Start(String pathFileName, Int32 BitmapRate) in d:C-SharpScreenVideoRecorderScreenVideoRecorderWorkingVersionFfmpeg.cs:line 39
at ScreenVideoRecorder.Form1.beginOperationToolStripMenuItem_Click(Object sender, EventArgs e) in d:C-SharpScreenVideoRecorderScreenVideoRecorderWorkingVersionForm1.cs:line 222
at System.Windows.Forms.ToolStripItem.RaiseEvent(Object key, EventArgs e)
at System.Windows.Forms.ToolStripMenuItem.OnClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleClick(EventArgs e)
at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
at System.Windows.Forms.ToolStripItem.FireEventInteractive(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStripItem.FireEvent(EventArgs e, ToolStripItemEventType met)
at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ToolStrip.WndProc(Message& m)
at System.Windows.Forms.ToolStripDropDown.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at ScreenVideoRecorder.Program.Main() in d:C-SharpScreenVideoRecorderScreenVideoRecorderWorkingVersionProgram.cs:line 18
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.AppDomain.nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.Runtime.Hosting.ManifestRunner.Run(Boolean checkAptModel)
at System.Runtime.Hosting.ManifestRunner.ExecuteAsAssembly()
at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext, String[] activationCustomData)
at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext)
at System.Activator.CreateInstance(ActivationContext activationContext)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssemblyDebugInZone()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException:



Why the exception show up ? And how can i fix it ?

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