From f9a23c660130e15c79fa410aa65bbc1ed1d3f51e Mon Sep 17 00:00:00 2001
From: firealarmss <caleb.k4php@gmail.com>
Date: Thu, 27 Feb 2025 02:50:55 -0600
Subject: [PATCH] Create a custom provider to allow for gain on received audio

---
 WhackerLinkConsoleV2/AudioManager.cs       | 18 ++++---
 WhackerLinkConsoleV2/ChannelBox.xaml       |  4 +-
 WhackerLinkConsoleV2/GainSampleProvider.cs | 58 ++++++++++++++++++++++
 3 files changed, 70 insertions(+), 10 deletions(-)
 create mode 100644 WhackerLinkConsoleV2/GainSampleProvider.cs

diff --git a/WhackerLinkConsoleV2/AudioManager.cs b/WhackerLinkConsoleV2/AudioManager.cs
index f190322..833d71c 100644
--- a/WhackerLinkConsoleV2/AudioManager.cs
+++ b/WhackerLinkConsoleV2/AudioManager.cs
@@ -29,7 +29,7 @@ namespace WhackerLinkConsoleV2
         private WaveOutEvent _waveOut;
         private MixingSampleProvider _mixer;
 
-        private Dictionary<string, (BufferedWaveProvider buffer, VolumeSampleProvider volumeProvider)> _talkgroupProviders;
+        private Dictionary<string, (BufferedWaveProvider buffer, GainSampleProvider gainProvider)> _talkgroupProviders;
 
         /// <summary>
         /// Creates an instance of <see cref="AudioManager"/>
@@ -37,7 +37,7 @@ namespace WhackerLinkConsoleV2
         public AudioManager()
         {
             _waveOut = new WaveOutEvent();
-            _talkgroupProviders = new Dictionary<string, (BufferedWaveProvider, VolumeSampleProvider)>();
+            _talkgroupProviders = new Dictionary<string, (BufferedWaveProvider, GainSampleProvider)>();
             _mixer = new MixingSampleProvider(WaveFormat.CreateIeeeFloatWaveFormat(8000, 1))
             {
                 ReadFully = true
@@ -71,13 +71,13 @@ namespace WhackerLinkConsoleV2
                 DiscardOnBufferOverflow = true
             };
 
-            var volumeProvider = new VolumeSampleProvider(bufferProvider.ToSampleProvider())
+            var gainProvider = new GainSampleProvider(bufferProvider.ToSampleProvider())
             {
-                Volume = 1.0f
+                Gain = 1.0f
             };
 
-            _talkgroupProviders[talkgroupId] = (bufferProvider, volumeProvider);
-            _mixer.AddMixerInput(volumeProvider);
+            _talkgroupProviders[talkgroupId] = (bufferProvider, gainProvider);
+            _mixer.AddMixerInput(gainProvider);
         }
 
         /// <summary>
@@ -86,11 +86,13 @@ namespace WhackerLinkConsoleV2
         public void SetTalkgroupVolume(string talkgroupId, float volume)
         {
             if (_talkgroupProviders.ContainsKey(talkgroupId))
-                _talkgroupProviders[talkgroupId].volumeProvider.Volume = volume;
+            {
+                _talkgroupProviders[talkgroupId].gainProvider.Gain = volume;
+            }
             else
             {
                 AddTalkgroupStream(talkgroupId);
-                _talkgroupProviders[talkgroupId].volumeProvider.Volume = volume;
+                _talkgroupProviders[talkgroupId].gainProvider.Gain = volume;
             }
         }
 
diff --git a/WhackerLinkConsoleV2/ChannelBox.xaml b/WhackerLinkConsoleV2/ChannelBox.xaml
index 62e302e..97244f0 100644
--- a/WhackerLinkConsoleV2/ChannelBox.xaml
+++ b/WhackerLinkConsoleV2/ChannelBox.xaml
@@ -22,8 +22,8 @@
             <Button Content="Page Select" Width="80" Margin="80,5,0,0" Background="Green" Foreground="White" Name="PageSelectButton"
                     HorizontalAlignment="Left" Grid.Row="3" Click="PageSelectButton_Click"/>
 
-            <Slider Grid.Row="4" Minimum="0" Maximum="1" Value="{Binding Volume, Mode=TwoWay}"
-                    Width="180" Margin="5" Name="VolumeSlider" ValueChanged="VolumeSlider_ValueChanged"/>
+            <Slider Grid.Row="4" Minimum="0" Maximum="4" Value="{Binding Volume, Mode=TwoWay}"
+                Width="180" Margin="5" Name="VolumeSlider" ValueChanged="VolumeSlider_ValueChanged"/>
         </Grid>
     </Border>
 </UserControl>
diff --git a/WhackerLinkConsoleV2/GainSampleProvider.cs b/WhackerLinkConsoleV2/GainSampleProvider.cs
new file mode 100644
index 0000000..eef28bf
--- /dev/null
+++ b/WhackerLinkConsoleV2/GainSampleProvider.cs
@@ -0,0 +1,58 @@
+/*
+* WhackerLink - WhackerLinkConsoleV2
+*
+* This program is free software: you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation, either version 3 of the License, or
+* (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program.  If not, see <http://www.gnu.org/licenses/>.
+* 
+* Copyright (C) 2025 Caleb, K4PHP
+* 
+*/
+
+using NAudio.Wave;
+using NAudio.Wave.SampleProviders;
+using System;
+
+namespace WhackerLinkConsoleV2
+{
+    public class GainSampleProvider : ISampleProvider
+    {
+        private readonly ISampleProvider _source;
+        private float _gain = 1.0f;
+
+        public GainSampleProvider(ISampleProvider source)
+        {
+            _source = source ?? throw new ArgumentNullException(nameof(source));
+            WaveFormat = source.WaveFormat;
+        }
+
+        public WaveFormat WaveFormat { get; }
+
+        public float Gain
+        {
+            get => _gain;
+            set => _gain = Math.Max(0, value);
+        }
+
+        public int Read(float[] buffer, int offset, int count)
+        {
+            int samplesRead = _source.Read(buffer, offset, count);
+
+            for (int i = 0; i < samplesRead; i++)
+            {
+                buffer[offset + i] *= _gain;
+            }
+
+            return samplesRead;
+        }
+    }
+}