Dart API for speaker diarization (#1418)

.github/scripts/test-dart.sh

@@ -4,6 +4,11 @@ set -ex
 
 cd dart-api-examples
 
+pushd speaker-diarization
+echo '----------speaker diarization----------'
+./run.sh
+popd
+
 pushd speaker-identification
 echo '----------3d speaker----------'
 ./run-3d-speaker.sh

.github/workflows/test-dart.yaml

@@ -114,6 +114,7 @@ jobs:
           cp scripts/dart/audio-tagging-pubspec.yaml dart-api-examples/audio-tagging/pubspec.yaml
           cp scripts/dart/add-punctuations-pubspec.yaml dart-api-examples/add-punctuations/pubspec.yaml
           cp scripts/dart/speaker-id-pubspec.yaml dart-api-examples/speaker-identification/pubspec.yaml
+          cp scripts/dart/speaker-diarization-pubspec.yaml dart-api-examples/speaker-diarization/pubspec.yaml
 
           cp scripts/dart/sherpa-onnx-pubspec.yaml flutter/sherpa_onnx/pubspec.yaml
 

dart-api-examples/README.md

@@ -9,6 +9,7 @@ https://pub.dev/packages/sherpa_onnx
 
 | Directory | Description |
 |-----------|-------------|
+| [./speaker-diarization](./speaker-diarization)| Example for speaker diarization.|
 | [./add-punctuations](./add-punctuations)| Example for adding punctuations to text.|
 | [./audio-tagging](./audio-tagging)| Example for audio tagging.|
 | [./keyword-spotter](./keyword-spotter)| Example for keyword spotting|

dart-api-examples/speaker-diarization/.gitignore

@@ -0,0 +1,3 @@
+# https://dart.dev/guides/libraries/private-files
+# Created by `dart pub`
+.dart_tool/

dart-api-examples/speaker-diarization/CHANGELOG.md

@@ -0,0 +1,3 @@
+## 1.0.0
+
+- Initial version.

dart-api-examples/speaker-diarization/README.md

@@ -0,0 +1,7 @@
+# Introduction
+
+This example shows how to use the Dart API from sherpa-onnx for speaker diarization.
+
+# Usage
+
+Please see [./run.sh](./run.sh)

dart-api-examples/speaker-diarization/analysis_options.yaml

@@ -0,0 +1,30 @@
+# This file configures the static analysis results for your project (errors,
+# warnings, and lints).
+#
+# This enables the 'recommended' set of lints from `package:lints`.
+# This set helps identify many issues that may lead to problems when running
+# or consuming Dart code, and enforces writing Dart using a single, idiomatic
+# style and format.
+#
+# If you want a smaller set of lints you can change this to specify
+# 'package:lints/core.yaml'. These are just the most critical lints
+# (the recommended set includes the core lints).
+# The core lints are also what is used by pub.dev for scoring packages.
+
+include: package:lints/recommended.yaml
+
+# Uncomment the following section to specify additional rules.
+
+# linter:
+#   rules:
+#     - camel_case_types
+
+# analyzer:
+#   exclude:
+#     - path/to/excluded/files/**
+
+# For more information about the core and recommended set of lints, see
+# https://dart.dev/go/core-lints
+
+# For additional information about configuring this file, see
+# https://dart.dev/guides/language/analysis-options

dart-api-examples/speaker-diarization/bin/init.dart

@@ -0,0 +1 @@
+../../vad/bin/init.dart

dart-api-examples/speaker-diarization/bin/speaker-diarization.dart

@@ -0,0 +1,100 @@
+// Copyright (c)  2024  Xiaomi Corporation
+import 'dart:io';
+import 'dart:typed_data';
+import 'dart:ffi';
+
+import 'package:sherpa_onnx/sherpa_onnx.dart' as sherpa_onnx;
+import './init.dart';
+
+void main(List<String> arguments) async {
+  await initSherpaOnnx();
+
+  /* Please use the following commands to download files used in this file
+    Step 1: Download a speaker segmentation model
+
+    Please visit https://github.com/k2-fsa/sherpa-onnx/releases/tag/speaker-segmentation-models
+    for a list of available models. The following is an example
+
+      wget https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-segmentation-models/sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+      tar xvf sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+      rm sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+
+    Step 2: Download a speaker embedding extractor model
+
+    Please visit https://github.com/k2-fsa/sherpa-onnx/releases/tag/speaker-recongition-models
+    for a list of available models. The following is an example
+
+      wget https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-recongition-models/3dspeaker_speech_eres2net_base_sv_zh-cn_3dspeaker_16k.onnx
+
+    Step 3. Download test wave files
+
+    Please visit https://github.com/k2-fsa/sherpa-onnx/releases/tag/speaker-segmentation-models
+    for a list of available test wave files. The following is an example
+
+      wget https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-segmentation-models/0-four-speakers-zh.wav
+
+    Step 4. Run it
+        */
+
+  final segmentationModel =
+      "./sherpa-onnx-pyannote-segmentation-3-0/model.onnx";
+
+  final embeddingModel =
+      "./3dspeaker_speech_eres2net_base_sv_zh-cn_3dspeaker_16k.onnx";
+
+  final waveFilename = "./0-four-speakers-zh.wav";
+
+  final segmentationConfig = sherpa_onnx.OfflineSpeakerSegmentationModelConfig(
+    pyannote: sherpa_onnx.OfflineSpeakerSegmentationPyannoteModelConfig(
+        model: segmentationModel),
+  );
+
+  final embeddingConfig =
+      sherpa_onnx.SpeakerEmbeddingExtractorConfig(model: embeddingModel);
+
+  // since we know there are 4 speakers in ./0-four-speakers-zh.wav, we set
+  // numClusters to 4. If you don't know the exact number, please set it to -1.
+  // in that case, you have to set threshold. A larger threshold leads to
+  // fewer clusters, i.e., fewer speakers.
+  final clusteringConfig =
+      sherpa_onnx.FastClusteringConfig(numClusters: 4, threshold: 0.5);
+
+  var config = sherpa_onnx.OfflineSpeakerDiarizationConfig(
+      segmentation: segmentationConfig,
+      embedding: embeddingConfig,
+      clustering: clusteringConfig,
+      minDurationOn: 0.2,
+      minDurationOff: 0.5);
+
+  final sd = sherpa_onnx.OfflineSpeakerDiarization(config);
+  if (sd.ptr == nullptr) {
+    return;
+  }
+
+  final waveData = sherpa_onnx.readWave(waveFilename);
+  if (sd.sampleRate != waveData.sampleRate) {
+    print(
+        'Expected sample rate: ${sd.sampleRate}, given: ${waveData.sampleRate}');
+    return;
+  }
+
+  print('started');
+
+  // Use the following statement if you don't want to use a callback
+  // final segments = sd.process(samples: waveData.samples);
+
+  final segments = sd.processWithCallback(
+      samples: waveData.samples,
+      callback: (int numProcessedChunk, int numTotalChunks) {
+        final progress = 100.0 * numProcessedChunk / numTotalChunks;
+
+        print('Progress ${progress.toStringAsFixed(2)}%');
+
+        return 0;
+      });
+
+  for (int i = 0; i < segments.length; ++i) {
+    print(
+        '${segments[i].start.toStringAsFixed(3)} -- ${segments[i].end.toStringAsFixed(3)}  speaker_${segments[i].speaker}');
+  }
+}

dart-api-examples/speaker-diarization/pubspec.yaml

@@ -0,0 +1,17 @@
+name: speaker_diarization
+description: >
+  This example demonstrates how to use the Dart API for speaker diarization.
+
+version: 1.0.0
+
+environment:
+  sdk: ">=3.0.0 <4.0.0"
+
+dependencies:
+  sherpa_onnx: ^1.10.27
+  # sherpa_onnx:
+  #   path: ../../flutter/sherpa_onnx
+  path: ^1.9.0
+
+dev_dependencies:
+  lints: ^3.0.0

dart-api-examples/speaker-diarization/run.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+set -ex
+
+dart pub get
+
+if [ ! -f ./sherpa-onnx-pyannote-segmentation-3-0/model.onnx ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-segmentation-models/sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+  tar xvf sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+  rm sherpa-onnx-pyannote-segmentation-3-0.tar.bz2
+fi
+
+if [ ! -f ./3dspeaker_speech_eres2net_base_sv_zh-cn_3dspeaker_16k.onnx ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-recongition-models/3dspeaker_speech_eres2net_base_sv_zh-cn_3dspeaker_16k.onnx
+fi
+
+if [ ! -f ./0-four-speakers-zh.wav ]; then
+  curl -SL -O https://github.com/k2-fsa/sherpa-onnx/releases/download/speaker-segmentation-models/0-four-speakers-zh.wav
+fi
+
+dart run ./bin/speaker-diarization.dart

flutter/sherpa_onnx/example/example.md

@@ -11,6 +11,7 @@
 
 | Functions | URL | Supported Platforms|
 |---|---|---|
+|Speaker diarization| [Address](https://github.com/k2-fsa/sherpa-onnx/tree/master/dart-api-examples/speaker-diarization)| macOS, Windows, Linux|
 |Streaming speech recognition| [Address](https://github.com/k2-fsa/sherpa-onnx/tree/master/dart-api-examples/streaming-asr)| macOS, Windows, Linux|
 |Non-Streaming speech recognition| [Address](https://github.com/k2-fsa/sherpa-onnx/tree/master/dart-api-examples/non-streaming-asr)| macOS, Windows, Linux|
 |Text to speech| [Address](https://github.com/k2-fsa/sherpa-onnx/tree/master/dart-api-examples/tts)| macOS, Windows, Linux|

flutter/sherpa_onnx/lib/sherpa_onnx.dart

@@ -6,6 +6,7 @@ export 'src/audio_tagging.dart';
 export 'src/feature_config.dart';
 export 'src/keyword_spotter.dart';
 export 'src/offline_recognizer.dart';
+export 'src/offline_speaker_diarization.dart';
 export 'src/offline_stream.dart';
 export 'src/online_recognizer.dart';
 export 'src/online_stream.dart';

flutter/sherpa_onnx/lib/src/offline_speaker_diarization.dart

@@ -0,0 +1,243 @@
+// Copyright (c)  2024  Xiaomi Corporation
+import 'dart:ffi';
+import 'dart:typed_data';
+
+import 'package:ffi/ffi.dart';
+
+import './sherpa_onnx_bindings.dart';
+import './speaker_identification.dart';
+
+class OfflineSpeakerDiarizationSegment {
+  const OfflineSpeakerDiarizationSegment({
+    required this.start,
+    required this.end,
+    required this.speaker,
+  });
+
+  @override
+  String toString() {
+    return 'OfflineSpeakerDiarizationSegment(start: $start, end: $end, speaker: $speaker)';
+  }
+
+  final double start;
+  final double end;
+  final int speaker;
+}
+
+class OfflineSpeakerSegmentationPyannoteModelConfig {
+  const OfflineSpeakerSegmentationPyannoteModelConfig({
+    this.model = '',
+  });
+
+  @override
+  String toString() {
+    return 'OfflineSpeakerSegmentationPyannoteModelConfig(model: $model)';
+  }
+
+  final String model;
+}
+
+class OfflineSpeakerSegmentationModelConfig {
+  const OfflineSpeakerSegmentationModelConfig({
+    this.pyannote = const OfflineSpeakerSegmentationPyannoteModelConfig(),
+    this.numThreads = 1,
+    this.debug = true,
+    this.provider = 'cpu',
+  });
+
+  @override
+  String toString() {
+    return 'OfflineSpeakerSegmentationModelConfig(pyannote: $pyannote, numThreads: $numThreads, debug: $debug, provider: $provider)';
+  }
+
+  final OfflineSpeakerSegmentationPyannoteModelConfig pyannote;
+
+  final int numThreads;
+  final bool debug;
+  final String provider;
+}
+
+class FastClusteringConfig {
+  const FastClusteringConfig({
+    this.numClusters = -1,
+    this.threshold = 0.5,
+  });
+
+  @override
+  String toString() {
+    return 'FastClusteringConfig(numClusters: $numClusters, threshold: $threshold)';
+  }
+
+  final int numClusters;
+  final double threshold;
+}
+
+class OfflineSpeakerDiarizationConfig {
+  const OfflineSpeakerDiarizationConfig({
+    this.segmentation = const OfflineSpeakerSegmentationModelConfig(),
+    this.embedding = const SpeakerEmbeddingExtractorConfig(model: ''),
+    this.clustering = const FastClusteringConfig(),
+    this.minDurationOn = 0.2,
+    this.minDurationOff = 0.5,
+  });
+
+  @override
+  String toString() {
+    return 'OfflineSpeakerDiarizationConfig(segmentation: $segmentation, embedding: $embedding, clustering: $clustering, minDurationOn: $minDurationOn, minDurationOff: $minDurationOff)';
+  }
+
+  final OfflineSpeakerSegmentationModelConfig segmentation;
+  final SpeakerEmbeddingExtractorConfig embedding;
+  final FastClusteringConfig clustering;
+  final double minDurationOff; // in seconds
+  final double minDurationOn; // in seconds
+}
+
+class OfflineSpeakerDiarization {
+  OfflineSpeakerDiarization._(
+      {required this.ptr, required this.config, required this.sampleRate});
+
+  void free() {
+    SherpaOnnxBindings.sherpaOnnxDestroyOfflineSpeakerDiarization?.call(ptr);
+    ptr = nullptr;
+  }
+
+  /// The user is responsible to call the OfflineSpeakerDiarization.free()
+  /// method of the returned instance to avoid memory leak.
+  factory OfflineSpeakerDiarization(OfflineSpeakerDiarizationConfig config) {
+    final c = calloc<SherpaOnnxOfflineSpeakerDiarizationConfig>();
+
+    c.ref.segmentation.pyannote.model =
+        config.segmentation.pyannote.model.toNativeUtf8();
+    c.ref.segmentation.numThreads = config.segmentation.numThreads;
+    c.ref.segmentation.debug = config.segmentation.debug ? 1 : 0;
+    c.ref.segmentation.provider = config.segmentation.provider.toNativeUtf8();
+
+    c.ref.embedding.model = config.embedding.model.toNativeUtf8();
+    c.ref.embedding.numThreads = config.embedding.numThreads;
+    c.ref.embedding.debug = config.embedding.debug ? 1 : 0;
+    c.ref.embedding.provider = config.embedding.provider.toNativeUtf8();
+
+    c.ref.clustering.numClusters = config.clustering.numClusters;
+    c.ref.clustering.threshold = config.clustering.threshold;
+
+    c.ref.minDurationOn = config.minDurationOn;
+    c.ref.minDurationOff = config.minDurationOff;
+
+    final ptr =
+        SherpaOnnxBindings.sherpaOnnxCreateOfflineSpeakerDiarization?.call(c) ??
+            nullptr;
+
+    calloc.free(c.ref.embedding.provider);
+    calloc.free(c.ref.embedding.model);
+    calloc.free(c.ref.segmentation.provider);
+    calloc.free(c.ref.segmentation.pyannote.model);
+
+    int sampleRate = 0;
+    if (ptr != nullptr) {
+      sampleRate = SherpaOnnxBindings
+              .sherpaOnnxOfflineSpeakerDiarizationGetSampleRate
+              ?.call(ptr) ??
+          0;
+    }
+    return OfflineSpeakerDiarization._(
+        ptr: ptr, config: config, sampleRate: sampleRate);
+  }
+
+  List<OfflineSpeakerDiarizationSegment> process(
+      {required Float32List samples}) {
+    if (ptr == nullptr) {
+      return <OfflineSpeakerDiarizationSegment>[];
+    }
+
+    final n = samples.length;
+    final Pointer<Float> p = calloc<Float>(n);
+
+    final pList = p.asTypedList(n);
+    pList.setAll(0, samples);
+
+    final r = SherpaOnnxBindings.sherpaOnnxOfflineSpeakerDiarizationProcess
+            ?.call(ptr, p, n) ??
+        nullptr;
+
+    final ans = _processImpl(r);
+
+    SherpaOnnxBindings.sherpaOnnxOfflineSpeakerDiarizationDestroyResult
+        ?.call(r);
+
+    return ans;
+  }
+
+  List<OfflineSpeakerDiarizationSegment> processWithCallback({
+    required Float32List samples,
+    required int Function(int numProcessedChunks, int numTotalChunks) callback,
+  }) {
+    if (ptr == nullptr) {
+      return <OfflineSpeakerDiarizationSegment>[];
+    }
+
+    final n = samples.length;
+    final Pointer<Float> p = calloc<Float>(n);
+
+    final pList = p.asTypedList(n);
+    pList.setAll(0, samples);
+
+    final wrapper = NativeCallable<
+            SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArgNative>.isolateLocal(
+        (int numProcessedChunks, int numTotalChunks) {
+      return callback(numProcessedChunks, numTotalChunks);
+    }, exceptionalReturn: 0);
+
+    final r = SherpaOnnxBindings
+            .sherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg
+            ?.call(ptr, p, n, wrapper.nativeFunction) ??
+        nullptr;
+
+    wrapper.close();
+
+    final ans = _processImpl(r);
+
+    SherpaOnnxBindings.sherpaOnnxOfflineSpeakerDiarizationDestroyResult
+        ?.call(r);
+
+    return ans;
+  }
+
+  List<OfflineSpeakerDiarizationSegment> _processImpl(
+      Pointer<SherpaOnnxOfflineSpeakerDiarizationResult> r) {
+    if (r == nullptr) {
+      return <OfflineSpeakerDiarizationSegment>[];
+    }
+
+    final numSegments = SherpaOnnxBindings
+            .sherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments
+            ?.call(r) ??
+        0;
+    final segments = SherpaOnnxBindings
+            .sherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime
+            ?.call(r) ??
+        nullptr;
+
+    if (segments == nullptr) {
+      return <OfflineSpeakerDiarizationSegment>[];
+    }
+
+    final ans = <OfflineSpeakerDiarizationSegment>[];
+    for (int i = 0; i != numSegments; ++i) {
+      final s = segments + i;
+
+      final tmp = OfflineSpeakerDiarizationSegment(
+          start: s.ref.start, end: s.ref.end, speaker: s.ref.speaker);
+      ans.add(tmp);
+    }
+
+    SherpaOnnxBindings.sherpaOnnxOfflineSpeakerDiarizationDestroySegment
+        ?.call(segments);
+
+    return ans;
+  }
+
+  Pointer<SherpaOnnxOfflineSpeakerDiarization> ptr;
+  OfflineSpeakerDiarizationConfig config;
+  final int sampleRate;
+}

flutter/sherpa_onnx/lib/src/sherpa_onnx_bindings.dart

@@ -2,6 +2,66 @@
 import 'dart:ffi';
 import 'package:ffi/ffi.dart';
 
+final class SherpaOnnxSpeakerEmbeddingExtractorConfig extends Struct {
+  external Pointer<Utf8> model;
+
+  @Int32()
+  external int numThreads;
+
+  @Int32()
+  external int debug;
+
+  external Pointer<Utf8> provider;
+}
+
+final class SherpaOnnxOfflineSpeakerDiarizationSegment extends Struct {
+  @Float()
+  external double start;
+
+  @Float()
+  external double end;
+
+  @Int32()
+  external int speaker;
+}
+
+final class SherpaOnnxOfflineSpeakerSegmentationPyannoteModelConfig
+    extends Struct {
+  external Pointer<Utf8> model;
+}
+
+final class SherpaOnnxOfflineSpeakerSegmentationModelConfig extends Struct {
+  external SherpaOnnxOfflineSpeakerSegmentationPyannoteModelConfig pyannote;
+
+  @Int32()
+  external int numThreads;
+
+  @Int32()
+  external int debug;
+
+  external Pointer<Utf8> provider;
+}
+
+final class SherpaOnnxFastClusteringConfig extends Struct {
+  @Int32()
+  external int numClusters;
+
+  @Float()
+  external double threshold;
+}
+
+final class SherpaOnnxOfflineSpeakerDiarizationConfig extends Struct {
+  external SherpaOnnxOfflineSpeakerSegmentationModelConfig segmentation;
+  external SherpaOnnxSpeakerEmbeddingExtractorConfig embedding;
+  external SherpaOnnxFastClusteringConfig clustering;
+
+  @Float()
+  external double minDurationOn;
+
+  @Float()
+  external double minDurationOff;
+}
+
 final class SherpaOnnxOfflinePunctuationModelConfig extends Struct {
   external Pointer<Utf8> ctTransformer;
 
@@ -341,18 +401,6 @@ final class SherpaOnnxWave extends Struct {
   external int numSamples;
 }
 
-final class SherpaOnnxSpeakerEmbeddingExtractorConfig extends Struct {
-  external Pointer<Utf8> model;
-
-  @Int32()
-  external int numThreads;
-
-  @Int32()
-  external int debug;
-
-  external Pointer<Utf8> provider;
-}
-
 final class SherpaOnnxKeywordSpotterConfig extends Struct {
   external SherpaOnnxFeatureConfig feat;
 
@@ -402,10 +450,101 @@ final class SherpaOnnxSpeakerEmbeddingExtractor extends Opaque {}
 
 final class SherpaOnnxSpeakerEmbeddingManager extends Opaque {}
 
+final class SherpaOnnxOfflineSpeakerDiarization extends Opaque {}
+
+final class SherpaOnnxOfflineSpeakerDiarizationResult extends Opaque {}
+
+typedef SherpaOnnxCreateOfflineSpeakerDiarizationNative
+    = Pointer<SherpaOnnxOfflineSpeakerDiarization> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarizationConfig>);
+
+typedef SherpaOnnxCreateOfflineSpeakerDiarization
+    = SherpaOnnxCreateOfflineSpeakerDiarizationNative;
+
+typedef SherpaOnnxDestroyOfflineSpeakerDiarizationNative = Void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>);
+
+typedef SherpaOnnxDestroyOfflineSpeakerDiarization = void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>);
+
 typedef SherpaOnnxCreateOfflinePunctuationNative
     = Pointer<SherpaOnnxOfflinePunctuation> Function(
         Pointer<SherpaOnnxOfflinePunctuationConfig>);
 
+typedef SherpaOnnxOfflineSpeakerDiarizationGetSampleRateNative = Int32 Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationGetSampleRate = int Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationSetConfigNative = Void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>,
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationConfig>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakersNative = Int32
+    Function(Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakers = int Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultGetNumSegmentsNative = Int32
+    Function(Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments = int Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTimeNative
+    = Pointer<SherpaOnnxOfflineSpeakerDiarizationSegment> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime
+    = SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTimeNative;
+
+typedef SherpaOnnxOfflineSpeakerDiarizationDestroySegmentNative = Void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationSegment>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationDestroySegment = void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationSegment>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationProcessNative
+    = Pointer<SherpaOnnxOfflineSpeakerDiarizationResult> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarization>, Pointer<Float>, Int32);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationProcess
+    = Pointer<SherpaOnnxOfflineSpeakerDiarizationResult> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarization>, Pointer<Float>, int);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArgNative = Int32
+    Function(Int32, Int32);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArgNative
+    = Pointer<SherpaOnnxOfflineSpeakerDiarizationResult> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarization>,
+        Pointer<Float>,
+        Int32,
+        Pointer<
+            NativeFunction<
+                SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArgNative>>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg
+    = Pointer<SherpaOnnxOfflineSpeakerDiarizationResult> Function(
+        Pointer<SherpaOnnxOfflineSpeakerDiarization>,
+        Pointer<Float>,
+        int,
+        Pointer<
+            NativeFunction<
+                SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArgNative>>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationDestroyResultNative = Void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationDestroyResult = void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationResult>);
+
+typedef SherpaOnnxOfflineSpeakerDiarizationSetConfig = void Function(
+    Pointer<SherpaOnnxOfflineSpeakerDiarization>,
+    Pointer<SherpaOnnxOfflineSpeakerDiarizationConfig>);
+
 typedef SherpaOnnxCreateOfflinePunctuation
     = SherpaOnnxCreateOfflinePunctuationNative;
 
@@ -940,6 +1079,29 @@ typedef SherpaOnnxFreeWaveNative = Void Function(Pointer<SherpaOnnxWave>);
 typedef SherpaOnnxFreeWave = void Function(Pointer<SherpaOnnxWave>);
 
 class SherpaOnnxBindings {
+  static SherpaOnnxCreateOfflineSpeakerDiarization?
+      sherpaOnnxCreateOfflineSpeakerDiarization;
+  static SherpaOnnxDestroyOfflineSpeakerDiarization?
+      sherpaOnnxDestroyOfflineSpeakerDiarization;
+  static SherpaOnnxOfflineSpeakerDiarizationGetSampleRate?
+      sherpaOnnxOfflineSpeakerDiarizationGetSampleRate;
+  static SherpaOnnxOfflineSpeakerDiarizationSetConfig?
+      sherpaOnnxOfflineSpeakerDiarizationSetConfig;
+  static SherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakers?
+      sherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakers;
+  static SherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments?
+      sherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments;
+  static SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime?
+      sherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime;
+  static SherpaOnnxOfflineSpeakerDiarizationDestroySegment?
+      sherpaOnnxOfflineSpeakerDiarizationDestroySegment;
+  static SherpaOnnxOfflineSpeakerDiarizationProcess?
+      sherpaOnnxOfflineSpeakerDiarizationProcess;
+  static SherpaOnnxOfflineSpeakerDiarizationDestroyResult?
+      sherpaOnnxOfflineSpeakerDiarizationDestroyResult;
+  static SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg?
+      sherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg;
+
   static SherpaOnnxCreateOfflinePunctuation? sherpaOnnxCreateOfflinePunctuation;
   static SherpaOnnxDestroyOfflinePunctuation?
       sherpaOnnxDestroyOfflinePunctuation;
@@ -1107,6 +1269,83 @@ class SherpaOnnxBindings {
   static SherpaOnnxFreeWave? freeWave;
 
   static void init(DynamicLibrary dynamicLibrary) {
+    sherpaOnnxCreateOfflineSpeakerDiarization ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxCreateOfflineSpeakerDiarizationNative>>(
+            'SherpaOnnxCreateOfflineSpeakerDiarization')
+        .asFunction();
+
+    sherpaOnnxDestroyOfflineSpeakerDiarization ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxDestroyOfflineSpeakerDiarizationNative>>(
+            'SherpaOnnxDestroyOfflineSpeakerDiarization')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationGetSampleRate ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationGetSampleRateNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationGetSampleRate')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationSetConfig ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationSetConfigNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationSetConfig')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakers ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakersNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationResultGetNumSpeakers')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationResultGetNumSegmentsNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationResultGetNumSegments')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTimeNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationResultSortByStartTime')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationDestroySegment ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationDestroySegmentNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationDestroySegment')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationProcess ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationProcessNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationProcess')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArgNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg')
+        .asFunction();
+
+    sherpaOnnxOfflineSpeakerDiarizationDestroyResult ??= dynamicLibrary
+        .lookup<
+                NativeFunction<
+                    SherpaOnnxOfflineSpeakerDiarizationDestroyResultNative>>(
+            'SherpaOnnxOfflineSpeakerDiarizationDestroyResult')
+        .asFunction();
+
     sherpaOnnxCreateOfflinePunctuation ??= dynamicLibrary
         .lookup<NativeFunction<SherpaOnnxCreateOfflinePunctuationNative>>(
             'SherpaOnnxCreateOfflinePunctuation')

flutter/sherpa_onnx/pubspec.yaml

@@ -1,8 +1,8 @@
 name: sherpa_onnx
 
 description: >
-  Speech recognition, speech synthesis, and speaker recognition using next-gen Kaldi
-  with onnxruntime without Internet connection.
+  Speech recognition, speech synthesis, speaker diarization, and speaker recognition
+  using next-gen Kaldi with onnxruntime without Internet connection.
 
 repository: https://github.com/k2-fsa/sherpa-onnx/tree/master/flutter
 
@@ -12,7 +12,7 @@ documentation: https://k2-fsa.github.io/sherpa/onnx/
 topics:
   - speech-recognition
   - speech-synthesis
-  - speaker-identification
+  - speaker-diarization
   - audio-tagging
   - voice-activity-detection
 
@@ -41,7 +41,7 @@ dependencies:
   sherpa_onnx_linux: ^1.10.27
   # sherpa_onnx_linux:
   #   path: ../sherpa_onnx_linux
-    #
+
   sherpa_onnx_windows: ^1.10.27
   # sherpa_onnx_windows:
   #   path: ../sherpa_onnx_windows

scripts/dart/speaker-diarization-pubspec.yaml

@@ -0,0 +1,16 @@
+name: speaker_diarization
+description: >
+  This example demonstrates how to use the Dart API for speaker diarization.
+
+version: 1.0.0
+
+environment:
+  sdk: ">=3.0.0 <4.0.0"
+
+dependencies:
+  sherpa_onnx:
+    path: ../../flutter/sherpa_onnx
+  path: ^1.9.0
+
+dev_dependencies:
+  lints: ^3.0.0

sherpa-onnx/c-api/c-api.cc

@@ -1828,4 +1828,20 @@ SherpaOnnxOfflineSpeakerDiarizationProcessWithCallback(
   return ans;
 }
 
+const SherpaOnnxOfflineSpeakerDiarizationResult *
+SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg(
+    const SherpaOnnxOfflineSpeakerDiarization *sd, const float *samples,
+    int32_t n,
+    SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArg callback) {
+  auto wrapper = [callback](int32_t num_processed_chunks,
+                            int32_t num_total_chunks, void *) {
+    return callback(num_processed_chunks, num_total_chunks);
+  };
+
+  auto ans = new SherpaOnnxOfflineSpeakerDiarizationResult;
+  ans->impl = sd->impl->Process(samples, n, wrapper);
+
+  return ans;
+}
+
 #endif

sherpa-onnx/c-api/c-api.h

@@ -1485,6 +1485,9 @@ SHERPA_ONNX_API void SherpaOnnxOfflineSpeakerDiarizationDestroySegment(
 typedef int32_t (*SherpaOnnxOfflineSpeakerDiarizationProgressCallback)(
     int32_t num_processed_chunk, int32_t num_total_chunks, void *arg);
 
+typedef int32_t (*SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArg)(
+    int32_t num_processed_chunk, int32_t num_total_chunks);
+
 // The user has to invoke SherpaOnnxOfflineSpeakerDiarizationDestroyResult()
 // to free the returned pointer to avoid memory leak.
 SHERPA_ONNX_API const SherpaOnnxOfflineSpeakerDiarizationResult *
@@ -1500,6 +1503,12 @@ SherpaOnnxOfflineSpeakerDiarizationProcessWithCallback(
     int32_t n, SherpaOnnxOfflineSpeakerDiarizationProgressCallback callback,
     void *arg);
 
+SHERPA_ONNX_API const SherpaOnnxOfflineSpeakerDiarizationResult *
+SherpaOnnxOfflineSpeakerDiarizationProcessWithCallbackNoArg(
+    const SherpaOnnxOfflineSpeakerDiarization *sd, const float *samples,
+    int32_t n,
+    SherpaOnnxOfflineSpeakerDiarizationProgressCallbackNoArg callback);
+
 SHERPA_ONNX_API void SherpaOnnxOfflineSpeakerDiarizationDestroyResult(
     const SherpaOnnxOfflineSpeakerDiarizationResult *r);
 

sherpa-onnx/csrc/offline-speaker-diarization-pyannote-impl.h

@@ -5,6 +5,7 @@
 #define SHERPA_ONNX_CSRC_OFFLINE_SPEAKER_DIARIZATION_PYANNOTE_IMPL_H_
 
 #include <algorithm>
+#include <memory>
 #include <unordered_map>
 #include <utility>
 #include <vector>

sherpa-onnx/jni/offline-speaker-diarization.cc

@@ -204,7 +204,8 @@ Java_com_k2fsa_sherpa_onnx_OfflineSpeakerDiarization_processWithCallback(
   jfloat *p = env->GetFloatArrayElements(samples, nullptr);
   jsize n = env->GetArrayLength(samples);
   auto segments =
-      sd->Process(p, n, callback_wrapper, (void *)arg).SortByStartTime();
+      sd->Process(p, n, callback_wrapper, reinterpret_cast<void *>(arg))
+          .SortByStartTime();
   env->ReleaseFloatArrayElements(samples, p, JNI_ABORT);
 
   return ProcessImpl(env, segments);