Skip to main content

Toying with audio in powershell

Controlling mute/unmute and the volume on you computer with powershell.


Add-Type -TypeDefinition @'

using System.Runtime.InteropServices;
[Guid("5CDF2C82-841E-4546-9722-0CF74078229A"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IAudioEndpointVolume {
  // f(), g(), ... are unused COM method slots. Define these if you care
  int f(); int g(); int h(); int i();
  int SetMasterVolumeLevelScalar(float fLevel, System.Guid pguidEventContext);
  int j();
  int GetMasterVolumeLevelScalar(out float pfLevel);
  int k(); int l(); int m(); int n();
  int SetMute([MarshalAs(UnmanagedType.Bool)] bool bMute, System.Guid pguidEventContext);
  int GetMute(out bool pbMute);
}
[Guid("D666063F-1587-4E43-81F1-B948E807363F"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IMMDevice {
  int Activate(ref System.Guid id, int clsCtx, int activationParams, out IAudioEndpointVolume aev);
}
[Guid("A95664D2-9614-4F35-A746-DE8DB63617E6"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IMMDeviceEnumerator {
  int f(); // Unused
  int GetDefaultAudioEndpoint(int dataFlow, int role, out IMMDevice endpoint);
}
[ComImport, Guid("BCDE0395-E52F-467C-8E3D-C4579291692E")] class MMDeviceEnumeratorComObject { }
public class Audio {
  static IAudioEndpointVolume Vol() {
    var enumerator = new MMDeviceEnumeratorComObject() as IMMDeviceEnumerator;
    IMMDevice dev = null;
    Marshal.ThrowExceptionForHR(enumerator.GetDefaultAudioEndpoint(/*eRender*/ 0, /*eMultimedia*/ 1, out dev));
    IAudioEndpointVolume epv = null;
    var epvid = typeof(IAudioEndpointVolume).GUID;
    Marshal.ThrowExceptionForHR(dev.Activate(ref epvid, /*CLSCTX_ALL*/ 23, 0, out epv));
    return epv;
  }
  public static float Volume {
    get {float v = -1; Marshal.ThrowExceptionForHR(Vol().GetMasterVolumeLevelScalar(out v)); return v;}
    set {Marshal.ThrowExceptionForHR(Vol().SetMasterVolumeLevelScalar(value, System.Guid.Empty));}
  }
  public static bool Mute {
    get { bool mute; Marshal.ThrowExceptionForHR(Vol().GetMute(out mute)); return mute; }
    set { Marshal.ThrowExceptionForHR(Vol().SetMute(value, System.Guid.Empty)); }
  }
}

'@


Okay, adding that type to the powershell session, you can now control the volume and mute the speakers like so:


# Unmute the speakers

[audio]::Mute = $false

# Mute the speakers

[audio]::Mute = $true

# Set volume to 20%

[audio]::Volume = 0.2

Now don’t go and get any ideas, using this for a prank for instance. Rumor has it that you can use this in an powershell remote session and in combination with the System.Speech.Synthesis.SpeechSynthesizer .net class you could do all kinds of damage in your office. Not that I have ever, ever tried to do this myself... I found this code on a forum, cant remember where, if i find it, I will post the link :-)

Cheers

Tore
 

Comments

Post a Comment

Popular posts from this blog

Serialize data with PowerShell

Currently I am working on a big new module. In this module, I need to persist data to disk and reprocess them at some point even if the module/PowerShell session was closed. I needed to serialize objects and save them to disk. It needed to be very efficient to be able to support a high volume of objects. Hence I decided to turn this serializer into a module called HashData. Other Serializing methods In PowerShell we have several possibilities to serialize objects. There are two cmdlets you can use which are built in: Export-CliXml ConvertTo-JSON Both are excellent options if you do not care about the size of the file. In my case I needed something lean and mean in terms of the size on disk for the serialized object. Lets do some tests to compare the different types: (Hashdata.Object.ps1) You might be curious why I do not use the Export-CliXML cmdlet and just use the [System.Management.Automation.PSSerializer]::Serialize static method. The static method will generate t

Something completely different – PoshARM

I needed a project for my Xmas holiday and I needed something remotely work related. Thus the dubious PoshARM PowerShell module was born and brought to life during my Xmas holiday. Simply put it is a module that lets you build – for now – simple Azure Resource Manager (ARM) templates with PowerShell .  The module can also import templates from a file or from the clipboard/string. Your partial template or ready made template can be exported as a PowerShell script. This blog post will walk you through how to use it and the features that is currently implemented.  Update 08.02.2017: The module is now published to the PowerShellGallery ( https://www.powershellgallery.com/packages/posharm ). It is still in beta version, however test coverage have increased and some bugs have been squashed during the testing. Also help is present, however somewhat lacking here and there. Update 18.01.2017: The module is now on GitHub. Here is the link to the repro  ( PoshARM on GitHub ) What