Process.start System.nullreferenceexception: Object reference not set to an instance of an object

Question

Ok so I am trying to start the process with the following parameters

When I try to start it though I get an System.nullreferenceexception: Object reference not set to an instance of an object

What am I doing wrong?

   Dim exepath As String = Application.StartupPath + "\bin\ffmpeg.exe"
    Dim sr As StreamReader
    Dim cmd As String = " -i """ + input + """ -ar 22050 -y """ + output + """"
    Dim ffmpegOutput As String
    proc.StartInfo.FileName = exepath
    proc.StartInfo.Arguments = cmd
    proc.StartInfo.UseShellExecute = False
    proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden
    proc.StartInfo.RedirectStandardError = True  'redirect ffmpegs output 
    'to our application
    proc.StartInfo.RedirectStandardOutput = True 'we don’t really need this
    proc.StartInfo.CreateNoWindow = True
    proc.Start() 

Answer 1

Your StreamReader is not initialized:

 Dim sr As StreamReader

Verify you are initializing it before using it furthur in the code.

Edit:

Since you specify that the exception is thrown on the proc.Start() , I would suggest you to declare a ProcessStartInfo, and use it with Process.Start()

For example:

Dim l As New ProcessStartInfo
l.FileName = exepath
' ...
Process.Start(l)