From 9e51636569818990ba9adf34c7b46c8cff6825cf Mon Sep 17 00:00:00 2001
From: Sekoree <me@sekoree.dev>
Date: Sun, 10 Jul 2022 18:33:54 +0200
Subject: [PATCH] Add option to use Real+Imaginary average value

---
 RendererUI/ViewModels/MainWindowViewModel.cs | 18 ++++++++
 RendererUI/Views/MainWindow.axaml            | 22 +++++++---
 SekoRenderer/Renderer.cs                     | 46 ++++++++++++++++----
 3 files changed, 72 insertions(+), 14 deletions(-)

diff --git a/RendererUI/ViewModels/MainWindowViewModel.cs b/RendererUI/ViewModels/MainWindowViewModel.cs
index 103bacb..4850d6a 100644
--- a/RendererUI/ViewModels/MainWindowViewModel.cs
+++ b/RendererUI/ViewModels/MainWindowViewModel.cs
@@ -34,10 +34,28 @@ public bool UseImaginaryFFTValues
             get => _renderer.UseImaginaryFFTValues;
             set
             {
+                if (value)
+                {
+                    UseImaginaryAndRealAverage = false;
+                }
                 _renderer.UseImaginaryFFTValues = value;
                 this.RaisePropertyChanged();
             }
         }
+        
+        public bool UseImaginaryAndRealAverage
+        {
+            get => _renderer.UseImaginaryAndRealAverage;
+            set
+            {
+                if (value)
+                {
+                    UseImaginaryFFTValues = false;
+                }
+                _renderer.UseImaginaryAndRealAverage = value;
+                this.RaisePropertyChanged();
+            }
+        }
 
         [Reactive] public ObservableCollection<string> FFTWindows { get; set; } = new();
         [Reactive] public string SelectedFFTWindow { get; set; }
diff --git a/RendererUI/Views/MainWindow.axaml b/RendererUI/Views/MainWindow.axaml
index ad8a767..8be6455 100644
--- a/RendererUI/Views/MainWindow.axaml
+++ b/RendererUI/Views/MainWindow.axaml
@@ -14,7 +14,7 @@
     </Design.DataContext>
 
     <Grid ColumnDefinitions="2*,Auto"
-          RowDefinitions="Auto,Auto,Auto,Auto"
+          RowDefinitions="Auto,Auto,Auto,Auto,Auto"
           Margin="10">
         <TextBox Grid.Column="0"
                  Grid.Row="0"
@@ -54,19 +54,31 @@
                     Spacing="10">
             <ComboBox Items="{Binding FFTWindows}"
                       SelectedItem="{Binding SelectedFFTWindow}"/>
+            <CheckBox IsChecked="{Binding UseImaginaryAndRealAverage}"
+                      Content="Use Real + Imaginary FFT Average"/>
+        </StackPanel>
+        
+        <StackPanel Grid.Column="0"
+                    Grid.ColumnSpan="2"
+                    Grid.Row="3"
+                    Margin="10"
+                    VerticalAlignment="Center"
+                    HorizontalAlignment="Stretch"
+                    Orientation="Horizontal"
+                    Spacing="10">
+            <CheckBox IsChecked="{Binding UseImaginaryFFTValues}"
+                      Content="Use Imaginary FFTs"/>
             <CheckBox IsChecked="{Binding UseFFTPositions}"
                       Content="Use FFT Positions"/>
-            <CheckBox IsChecked="{Binding UseImaginaryFFTValues}"
-                      Content="Use Imaginary FFT Values"/>
         </StackPanel>
         
         <TextBlock Grid.Column="0"
-                   Grid.Row="3"
+                   Grid.Row="4"
                    Margin="10"
                    VerticalAlignment="Center" 
                    Text="{Binding OutputText, StringFormat=Output: {0}}"/>
         <Button Grid.Column="1"
-                Grid.Row="3"
+                Grid.Row="4"
                 Margin="10"
                 HorizontalAlignment="Stretch"
                 Content="Render"
diff --git a/SekoRenderer/Renderer.cs b/SekoRenderer/Renderer.cs
index dc5e9cc..2ac1d14 100644
--- a/SekoRenderer/Renderer.cs
+++ b/SekoRenderer/Renderer.cs
@@ -10,22 +10,29 @@ public class Renderer
 {
     public bool UseFFTPositions { get; set; }
     public bool UseImaginaryFFTValues { get; set; }
+    public bool UseImaginaryAndRealAverage { get; set; }
 
     public delegate double _fftWindow(int n, int frameSize);
     public _fftWindow FFTWindow { get; set; }
 
-    public Renderer()
+    private int _fftResolution;
+
+    public Renderer(int fftResolution = 512)
     {
         UseFFTPositions = true;
         UseImaginaryFFTValues = true;
+        UseImaginaryAndRealAverage = false;
         FFTWindow = FastFourierTransform.HannWindow;
+        _fftResolution = fftResolution;
     }
 
-    public Renderer(ref _fftWindow fftWindow, bool useFFTPositions = true, bool useImaginaryFFTValues = true)
+    public Renderer(ref _fftWindow fftWindow, bool useFFTPositions = true, bool useImaginaryFFTValues = true, bool useImaginaryAndRealAverage = false, int fftResolution = 512)
     {
         UseFFTPositions = useFFTPositions;
         UseImaginaryFFTValues = useImaginaryFFTValues;
+        UseImaginaryAndRealAverage = useImaginaryAndRealAverage;
         FFTWindow = fftWindow;
+        _fftResolution = fftResolution;
     }
     
     public string Md5HashFile(string fileName)
@@ -69,7 +76,7 @@ public void WriteAshFile(string path, string outputFolder, List<float> sums)
         }
 
         sbyte[]? shape = null;
-        int numShapeNodes = 256;
+        int numShapeNodes = _fftResolution / 2;
         Console.WriteLine("Creating shape");
         if (fileStream != null)
         {
@@ -111,7 +118,7 @@ public void WriteAshFile(string path, string outputFolder, List<float> sums)
     
     public List<float> DecodeSongSums(string path)
     {
-        var fft = new float[512];
+        var fft = new float[_fftResolution];
         
         var could = Bass.Init();
         Console.WriteLine("Bass.Init returned " + could);
@@ -138,19 +145,35 @@ public List<float> DecodeSongSums(string path)
     private float FastDecodeStepAsync(int chan, float[] ffts)
     {
         int fftPos = 0;
-        var data = Bass.ChannelGetData(chan, ffts, (int)DataFlags.FFT1024);
+        var defaultData = DataFlags.FFT1024;
+        if (_fftResolution == 128)
+            defaultData = DataFlags.FFT256;
+        else if (_fftResolution == 256)
+            defaultData = DataFlags.FFT512;
+        else if (_fftResolution == 1024)
+            defaultData = DataFlags.FFT2048;
+        else if (_fftResolution == 2048)
+            defaultData = DataFlags.FFT4096;
+        else if (_fftResolution == 4096)
+            defaultData = DataFlags.FFT8192;
+        else if (_fftResolution == 8192)
+            defaultData = DataFlags.FFT16384;
+        else if (_fftResolution == 16384)
+            defaultData = DataFlags.FFT32768;
+        
+        var data = Bass.ChannelGetData(chan, ffts, (int)defaultData);
 
         var complexFFTs = new Complex[ffts.Length];
         for (int i = 0; i < ffts.Length; i++)
         {
-            complexFFTs[i] = new Complex(ffts[i] * FFTWindow.Invoke(fftPos, 512), 0);
+            complexFFTs[i] = new Complex(ffts[i] * FFTWindow.Invoke(fftPos, _fftResolution), 0);
             if (UseFFTPositions)
             {
                 fftPos++;   
             }
         }
         
-        FastFourierTransform.FFT(false, (int)Math.Log(512, 2.0), ref complexFFTs);
+        FastFourierTransform.FFT(false, (int)Math.Log(_fftResolution, 2.0), ref complexFFTs);
         
         int fFT512KISS = data;
         if (fFT512KISS < 1)
@@ -159,9 +182,14 @@ private float FastDecodeStepAsync(int chan, float[] ffts)
         }
 
         float num = 0f;
-        for (int i = 1; i < 512; i++)
+        for (int i = 1; i < _fftResolution; i++)
         {
-            if (UseImaginaryFFTValues)
+            if (UseImaginaryAndRealAverage)
+            {
+                var avg = (complexFFTs[i].Real + complexFFTs[i].Imaginary) / 2;
+                num += (float)Math.Sqrt(Math.Max(0f, avg));
+            }
+            else if (UseImaginaryFFTValues)
             {
                 num += (float)Math.Sqrt(Math.Max(0f, complexFFTs[i].Imaginary));
             }