[GUI] Added Atrac9 audio decoder and improved GUI with audio preview and controller support (#64)

* [GUI] Added Atrac9 audio decoder and improved GUI with audio preview and controller support * fix: package.lock.json for SharpEmu.CLI to match the other projects * fix: packages.lock.json file to include new dependencies for GUI improvements * rollForward: "disable"
2026-07-31 06:59:45 +08:00 · 2026-07-11 19:14:08 +03:00
parent f43f7cde9c
commit 79a7437cd8
37 changed files with 4601 additions and 77 deletions
@@ -0,0 +1,178 @@
+#nullable disable
+using System;
+using System.Collections.Generic;
+
+namespace LibAtrac9.Utilities
+{
+    internal class Mdct
+    {
+        private int MdctBits { get; }
+        private int MdctSize { get; }
+        private double Scale { get; }
+
+        private static readonly object TableLock = new object();
+        private static int _tableBits = -1;
+        private static readonly List<double[]> SinTables = new List<double[]>();
+        private static readonly List<double[]> CosTables = new List<double[]>();
+        private static readonly List<int[]> ShuffleTables = new List<int[]>();
+
+        private readonly double[] _imdctPrevious;
+        private readonly double[] _imdctWindow;
+
+        private readonly double[] _scratchMdct;
+        private readonly double[] _scratchDct;
+
+        public Mdct(int mdctBits, double[] window, double scale = 1)
+        {
+            SetTables(mdctBits);
+
+            MdctBits = mdctBits;
+            MdctSize = 1 << mdctBits;
+            Scale = scale;
+
+            if (window.Length < MdctSize)
+            {
+                throw new ArgumentException("Window must be as long as the MDCT size.", nameof(window));
+            }
+
+            _imdctPrevious = new double[MdctSize];
+            _scratchMdct = new double[MdctSize];
+            _scratchDct = new double[MdctSize];
+            _imdctWindow = window;
+        }
+
+        private static void SetTables(int maxBits)
+        {
+            lock (TableLock)
+            {
+                if (maxBits > _tableBits)
+                {
+                    for (int i = _tableBits + 1; i <= maxBits; i++)
+                    {
+                        GenerateTrigTables(i, out double[] sin, out double[] cos);
+                        SinTables.Add(sin);
+                        CosTables.Add(cos);
+                        ShuffleTables.Add(GenerateShuffleTable(i));
+                    }
+                    _tableBits = maxBits;
+                }
+            }
+        }
+
+        public void RunImdct(double[] input, double[] output)
+        {
+            if (input.Length < MdctSize)
+            {
+                throw new ArgumentException("Input must be as long as the MDCT size.", nameof(input));
+            }
+
+            if (output.Length < MdctSize)
+            {
+                throw new ArgumentException("Output must be as long as the MDCT size.", nameof(output));
+            }
+
+            int size = MdctSize;
+            int half = size / 2;
+            double[] dctOut = _scratchMdct;
+
+            Dct4(input, dctOut);
+
+            for (int i = 0; i < half; i++)
+            {
+                output[i] = _imdctWindow[i] * dctOut[i + half] + _imdctPrevious[i];
+                output[i + half] = _imdctWindow[i + half] * -dctOut[size - 1 - i] - _imdctPrevious[i + half];
+                _imdctPrevious[i] = _imdctWindow[size - 1 - i] * -dctOut[half - i - 1];
+                _imdctPrevious[i + half] = _imdctWindow[half - i - 1] * dctOut[i];
+            }
+        }
+
+        /// <summary>
+        /// Does a Type-4 DCT.
+        /// </summary>
+        /// <param name="input">The input array containing the time or frequency-domain samples</param>
+        /// <param name="output">The output array that will contain the transformed time or frequency-domain samples</param>
+        private void Dct4(double[] input, double[] output)
+        {
+            int[] shuffleTable = ShuffleTables[MdctBits];
+            double[] sinTable = SinTables[MdctBits];
+            double[] cosTable = CosTables[MdctBits];
+            double[] dctTemp = _scratchDct;
+
+            int size = MdctSize;
+            int lastIndex = size - 1;
+            int halfSize = size / 2;
+
+            for (int i = 0; i < halfSize; i++)
+            {
+                int i2 = i * 2;
+                double a = input[i2];
+                double b = input[lastIndex - i2];
+                double sin = sinTable[i];
+                double cos = cosTable[i];
+                dctTemp[i2] = a * cos + b * sin;
+                dctTemp[i2 + 1] = a * sin - b * cos;
+            }
+            int stageCount = MdctBits - 1;
+
+            for (int stage = 0; stage < stageCount; stage++)
+            {
+                int blockCount = 1 << stage;
+                int blockSizeBits = stageCount - stage;
+                int blockHalfSizeBits = blockSizeBits - 1;
+                int blockSize = 1 << blockSizeBits;
+                int blockHalfSize = 1 << blockHalfSizeBits;
+                sinTable = SinTables[blockHalfSizeBits];
+                cosTable = CosTables[blockHalfSizeBits];
+
+                for (int block = 0; block < blockCount; block++)
+                {
+                    for (int i = 0; i < blockHalfSize; i++)
+                    {
+                        int frontPos = (block * blockSize + i) * 2;
+                        int backPos = frontPos + blockSize;
+                        double a = dctTemp[frontPos] - dctTemp[backPos];
+                        double b = dctTemp[frontPos + 1] - dctTemp[backPos + 1];
+                        double sin = sinTable[i];
+                        double cos = cosTable[i];
+                        dctTemp[frontPos] += dctTemp[backPos];
+                        dctTemp[frontPos + 1] += dctTemp[backPos + 1];
+                        dctTemp[backPos] = a * cos + b * sin;
+                        dctTemp[backPos + 1] = a * sin - b * cos;
+                    }
+                }
+            }
+
+            for (int i = 0; i < MdctSize; i++)
+            {
+                output[i] = dctTemp[shuffleTable[i]] * Scale;
+            }
+        }
+
+        internal static void GenerateTrigTables(int sizeBits, out double[] sin, out double[] cos)
+        {
+            int size = 1 << sizeBits;
+            sin = new double[size];
+            cos = new double[size];
+
+            for (int i = 0; i < size; i++)
+            {
+                double value = Math.PI * (4 * i + 1) / (4 * size);
+                sin[i] = Math.Sin(value);
+                cos[i] = Math.Cos(value);
+            }
+        }
+
+        internal static int[] GenerateShuffleTable(int sizeBits)
+        {
+            int size = 1 << sizeBits;
+            var table = new int[size];
+
+            for (int i = 0; i < size; i++)
+            {
+                table[i] = Bit.BitReverse32(i ^ (i / 2), sizeBits);
+            }
+
+            return table;
+        }
+    }
+}