From 41bba5310a5324f54fa5c0200aff2bf697ced000 Mon Sep 17 00:00:00 2001 From: merry Date: Sun, 15 Jan 2023 04:20:49 +0000 Subject: [PATCH] Audren: Implement polyphase upsampler (#4256) * Audren: Implement polyphase upsampler * prefer shifting to modulo * prefer MathF * fix nits * rm ResampleForUpsampler * oop * Array20 * nits --- .../Renderer/Dsp/Command/UpsampleCommand.cs | 12 +- Ryujinx.Audio/Renderer/Dsp/ResamplerHelper.cs | 47 ----- Ryujinx.Audio/Renderer/Dsp/UpsamplerHelper.cs | 175 ++++++++++++++++++ .../Server/Upsampler/UpsamplerBufferState.cs | 14 ++ .../Server/Upsampler/UpsamplerState.cs | 5 + 5 files changed, 201 insertions(+), 52 deletions(-) create mode 100644 Ryujinx.Audio/Renderer/Dsp/UpsamplerHelper.cs create mode 100644 Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerBufferState.cs diff --git a/Ryujinx.Audio/Renderer/Dsp/Command/UpsampleCommand.cs b/Ryujinx.Audio/Renderer/Dsp/Command/UpsampleCommand.cs index 1617a6421d..0870d59ce7 100644 --- a/Ryujinx.Audio/Renderer/Dsp/Command/UpsampleCommand.cs +++ b/Ryujinx.Audio/Renderer/Dsp/Command/UpsampleCommand.cs @@ -40,6 +40,12 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command info.InputBufferIndices[i] = (ushort)(bufferOffset + inputBufferOffset[i]); } + if (info.BufferStates?.Length != (int)inputCount) + { + // Keep state if possible. + info.BufferStates = new UpsamplerBufferState[(int)inputCount]; + } + UpsamplerInfo = info; } @@ -50,8 +56,6 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command public void Process(CommandList context) { - float ratio = (float)InputSampleRate / Constants.TargetSampleRate; - uint bufferCount = Math.Min(BufferCount, UpsamplerInfo.SourceSampleCount); for (int i = 0; i < bufferCount; i++) @@ -59,9 +63,7 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command Span inputBuffer = context.GetBuffer(UpsamplerInfo.InputBufferIndices[i]); Span outputBuffer = GetBuffer(UpsamplerInfo.InputBufferIndices[i], (int)UpsamplerInfo.SampleCount); - float fraction = 0.0f; - - ResamplerHelper.ResampleForUpsampler(outputBuffer, inputBuffer, ratio, ref fraction, (int)(InputSampleCount / ratio)); + UpsamplerHelper.Upsample(outputBuffer, inputBuffer, (int)UpsamplerInfo.SampleCount, (int)InputSampleCount, ref UpsamplerInfo.BufferStates[i]); } } } diff --git a/Ryujinx.Audio/Renderer/Dsp/ResamplerHelper.cs b/Ryujinx.Audio/Renderer/Dsp/ResamplerHelper.cs index 4de2e078a9..b46a33fe06 100644 --- a/Ryujinx.Audio/Renderer/Dsp/ResamplerHelper.cs +++ b/Ryujinx.Audio/Renderer/Dsp/ResamplerHelper.cs @@ -579,52 +579,5 @@ namespace Ryujinx.Audio.Renderer.Dsp fraction -= (int)fraction; } } - - [MethodImpl(MethodImplOptions.AggressiveInlining)] - public static void ResampleForUpsampler(Span outputBuffer, ReadOnlySpan inputBuffer, float ratio, ref float fraction, int sampleCount) - { - // Currently a simple cubic interpolation, assuming duplicated values at edges. - // TODO: Discover and use algorithm that the switch uses. - - int inputBufferIndex = 0; - int maxIndex = inputBuffer.Length - 1; - int cubicEnd = inputBuffer.Length - 3; - - for (int i = 0; i < sampleCount; i++) - { - float s0, s1, s2, s3; - - s1 = inputBuffer[inputBufferIndex]; - - if (inputBufferIndex == 0 || inputBufferIndex > cubicEnd) - { - // Clamp interplation values at the ends of the input buffer. - s0 = inputBuffer[Math.Max(0, inputBufferIndex - 1)]; - s2 = inputBuffer[Math.Min(maxIndex, inputBufferIndex + 1)]; - s3 = inputBuffer[Math.Min(maxIndex, inputBufferIndex + 2)]; - } - else - { - s0 = inputBuffer[inputBufferIndex - 1]; - s2 = inputBuffer[inputBufferIndex + 1]; - s3 = inputBuffer[inputBufferIndex + 2]; - } - - float a = s3 - s2 - s0 + s1; - float b = s0 - s1 - a; - float c = s2 - s0; - float d = s1; - - float f2 = fraction * fraction; - float f3 = f2 * fraction; - - outputBuffer[i] = a * f3 + b * f2 + c * fraction + d; - - fraction += ratio; - inputBufferIndex += (int)MathF.Truncate(fraction); - - fraction -= (int)fraction; - } - } } } \ No newline at end of file diff --git a/Ryujinx.Audio/Renderer/Dsp/UpsamplerHelper.cs b/Ryujinx.Audio/Renderer/Dsp/UpsamplerHelper.cs new file mode 100644 index 0000000000..847acec2e9 --- /dev/null +++ b/Ryujinx.Audio/Renderer/Dsp/UpsamplerHelper.cs @@ -0,0 +1,175 @@ +using Ryujinx.Audio.Renderer.Server.Upsampler; +using Ryujinx.Common.Memory; +using System; +using System.Diagnostics; +using System.Runtime.CompilerServices; + +namespace Ryujinx.Audio.Renderer.Dsp +{ + public class UpsamplerHelper + { + private const int HistoryLength = UpsamplerBufferState.HistoryLength; + private const int FilterBankLength = 20; + // Bank0 = [0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]; + private const int Bank0CenterIndex = 9; + private static readonly Array20 Bank1 = PrecomputeFilterBank(1.0f / 6.0f); + private static readonly Array20 Bank2 = PrecomputeFilterBank(2.0f / 6.0f); + private static readonly Array20 Bank3 = PrecomputeFilterBank(3.0f / 6.0f); + private static readonly Array20 Bank4 = PrecomputeFilterBank(4.0f / 6.0f); + private static readonly Array20 Bank5 = PrecomputeFilterBank(5.0f / 6.0f); + + private static Array20 PrecomputeFilterBank(float offset) + { + float Sinc(float x) + { + if (x == 0) + { + return 1.0f; + } + return (MathF.Sin(MathF.PI * x) / (MathF.PI * x)); + } + + float BlackmanWindow(float x) + { + const float a = 0.18f; + const float a0 = 0.5f - 0.5f * a; + const float a1 = -0.5f; + const float a2 = 0.5f * a; + return a0 + a1 * MathF.Cos(2 * MathF.PI * x) + a2 * MathF.Cos(4 * MathF.PI * x); + } + + Array20 result = new Array20(); + + for (int i = 0; i < FilterBankLength; i++) + { + float x = (Bank0CenterIndex - i) + offset; + result[i] = Sinc(x) * BlackmanWindow(x / FilterBankLength + 0.5f); + } + + return result; + } + + // Polyphase upsampling algorithm + [MethodImpl(MethodImplOptions.AggressiveInlining)] + public static void Upsample(Span outputBuffer, ReadOnlySpan inputBuffer, int outputSampleCount, int inputSampleCount, ref UpsamplerBufferState state) + { + if (!state.Initialized) + { + state.Scale = inputSampleCount switch + { + 40 => 6.0f, + 80 => 3.0f, + 160 => 1.5f, + _ => throw new ArgumentOutOfRangeException() + }; + state.Initialized = true; + } + + if (outputSampleCount == 0) + { + return; + } + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + float DoFilterBank(ref UpsamplerBufferState state, in Array20 bank) + { + float result = 0.0f; + + Debug.Assert(state.History.Length == HistoryLength); + Debug.Assert(bank.Length == FilterBankLength); + for (int j = 0; j < FilterBankLength; j++) + { + result += bank[j] * state.History[j]; + } + + return result; + } + + [MethodImpl(MethodImplOptions.AggressiveInlining)] + void NextInput(ref UpsamplerBufferState state, float input) + { + state.History.AsSpan().Slice(1).CopyTo(state.History.AsSpan()); + state.History[HistoryLength - 1] = input; + } + + int inputBufferIndex = 0; + + switch (state.Scale) + { + case 6.0f: + for (int i = 0; i < outputSampleCount; i++) + { + switch (state.Phase) + { + case 0: + NextInput(ref state, inputBuffer[inputBufferIndex++]); + outputBuffer[i] = state.History[Bank0CenterIndex]; + break; + case 1: + outputBuffer[i] = DoFilterBank(ref state, Bank1); + break; + case 2: + outputBuffer[i] = DoFilterBank(ref state, Bank2); + break; + case 3: + outputBuffer[i] = DoFilterBank(ref state, Bank3); + break; + case 4: + outputBuffer[i] = DoFilterBank(ref state, Bank4); + break; + case 5: + outputBuffer[i] = DoFilterBank(ref state, Bank5); + break; + } + + state.Phase = (state.Phase + 1) % 6; + } + break; + case 3.0f: + for (int i = 0; i < outputSampleCount; i++) + { + switch (state.Phase) + { + case 0: + NextInput(ref state, inputBuffer[inputBufferIndex++]); + outputBuffer[i] = state.History[Bank0CenterIndex]; + break; + case 1: + outputBuffer[i] = DoFilterBank(ref state, Bank2); + break; + case 2: + outputBuffer[i] = DoFilterBank(ref state, Bank4); + break; + } + + state.Phase = (state.Phase + 1) % 3; + } + break; + case 1.5f: + // Upsample by 3 then decimate by 2. + for (int i = 0; i < outputSampleCount; i++) + { + switch (state.Phase) + { + case 0: + NextInput(ref state, inputBuffer[inputBufferIndex++]); + outputBuffer[i] = state.History[Bank0CenterIndex]; + break; + case 1: + outputBuffer[i] = DoFilterBank(ref state, Bank4); + break; + case 2: + NextInput(ref state, inputBuffer[inputBufferIndex++]); + outputBuffer[i] = DoFilterBank(ref state, Bank2); + break; + } + + state.Phase = (state.Phase + 1) % 3; + } + break; + default: + throw new ArgumentOutOfRangeException(); + } + } + } +} \ No newline at end of file diff --git a/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerBufferState.cs b/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerBufferState.cs new file mode 100644 index 0000000000..a45fa8e5be --- /dev/null +++ b/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerBufferState.cs @@ -0,0 +1,14 @@ +using Ryujinx.Common.Memory; + +namespace Ryujinx.Audio.Renderer.Server.Upsampler +{ + public struct UpsamplerBufferState + { + public const int HistoryLength = 20; + + public float Scale; + public Array20 History; + public bool Initialized; + public int Phase; + } +} \ No newline at end of file diff --git a/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerState.cs b/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerState.cs index 065e4838c7..e508f35b46 100644 --- a/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerState.cs +++ b/Ryujinx.Audio/Renderer/Server/Upsampler/UpsamplerState.cs @@ -37,6 +37,11 @@ namespace Ryujinx.Audio.Renderer.Server.Upsampler /// public ushort[] InputBufferIndices; + /// + /// State of each input buffer index kept across invocations of the upsampler. + /// + public UpsamplerBufferState[] BufferStates; + /// /// Create a new . ///