SpeexDspSharp

C# bindings for SpeexDSP echo cancellation and preprocessing with bundled native runtime libraries.

The NuGet package id is tryAGI.SpeexDspSharp. The public namespace remains SpeexDspSharp.

Installation

dotnet add package tryAGI.SpeexDspSharp

Echo Cancellation

using SpeexDspSharp;

var sampleRate = 16000;
var frameSize = sampleRate / 50; // 20 ms
var filterLength = sampleRate / 5; // 200 ms

using var echo = new SpeexEchoState(sampleRate, frameSize, filterLength);

var playback = new short[frameSize];
var microphone = new short[frameSize];
var cleaned = new short[frameSize];

echo.RegisterPlayback(playback);
echo.Capture(microphone, cleaned);

SpeexEchoState wraps SpeexDSP's streaming API. Playback and capture frames must be exactly FrameSize 16-bit mono samples.

Native Libraries

The package contains native runtime assets under NuGet runtimes/<rid>/native/:

• runtimes/win-x64/native/speexdsp.dll
• runtimes/osx-x64/native/libspeexdsp.dylib
• runtimes/osx-arm64/native/libspeexdsp.dylib
• runtimes/linux-x64/native/libspeexdsp.so
• runtimes/linux-arm64/native/libspeexdsp.so

The native binaries are committed in natives/ so consumers do not need a system SpeexDSP installation.

Refreshing Native Binaries

Run the refresh script from the repository root:

natives/refresh.sh

The script stages Linux binaries from Debian packages, Windows x64 from MSYS2, and macOS from Homebrew.

Build And Test

dotnet build SpeexDspSharp.slnx
dotnet test src/tests/SpeexDspSharp.Tests/SpeexDspSharp.Tests.csproj
dotnet pack src/libs/SpeexDspSharp/SpeexDspSharp.csproj -c Release

License

SpeexDspSharp is licensed under MIT. Bundled SpeexDSP native binaries retain the upstream BSD license; see THIRD-PARTY-NOTICES.md.