detectSoundlevel-spike/sourceCode/trunk/Code/CoreAudio/Interfaces/ISimpleAudioVolume.cs

// -----------------------------------------
// SoundScribe (TM) and related software.
// 
// Copyright (C) 2007-2011 Vannatech
// http://www.vannatech.com
// All rights reserved.
// 
// This source code is subject to the MIT License.
// http://www.opensource.org/licenses/mit-license.php
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// -----------------------------------------

using System;
using System.Runtime.InteropServices;

namespace Vannatech.CoreAudio.Interfaces
{
    /// <summary>
	/// Enables a client to control the master volume level of an audio session. 
    /// </summary>
    /// <remarks>
	/// MSDN Reference: http://msdn.microsoft.com/en-us/library/dd316531.aspx
    /// </remarks>
	public partial interface ISimpleAudioVolume
    {
		/// <summary>
		/// Sets the master volume level for the audio session.
		/// </summary>
		/// <param name="levelNorm">The new volume level expressed as a normalized value between 0.0 and 1.0.</param>
		/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int SetMasterVolume(
			[In] [MarshalAs(UnmanagedType.R4)] float levelNorm,
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

		/// <summary>
		/// Retrieves the client volume level for the audio session.
		/// </summary>
		/// <param name="levelNorm">Receives the volume level expressed as a normalized value between 0.0 and 1.0. </param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetMasterVolume(
			[Out] [MarshalAs(UnmanagedType.R4)] out float levelNorm);

		/// <summary>
		/// Sets the muting state for the audio session.
		/// </summary>
		/// <param name="isMuted">The new muting state.</param>
		/// <param name="eventContext">A user context value that is passed to the notification callback.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int SetMute(
			[In] [MarshalAs(UnmanagedType.Bool)] bool isMuted,
			[In] [MarshalAs(UnmanagedType.LPStruct)] Guid eventContext);

		/// <summary>
		/// Retrieves the current muting state for the audio session.
		/// </summary>
		/// <param name="isMuted">Receives the muting state.</param>
		/// <returns>An HRESULT code indicating whether the operation succeeded of failed.</returns>
		[PreserveSig]
		int GetMute(
			[Out] [MarshalAs(UnmanagedType.Bool)] out bool isMuted);
    }
}