Java for Android

We provide two Android demos for streaming speech recognition. Both use JitPack to fetch the sherpa-onnx dependency, so there is no need to build native libraries manually.

Demo 1: SherpaOnnxJavaDemo (Groovy DSL)

A Java-based Android demo for streaming speech recognition.

https://github.com/k2-fsa/sherpa-onnx/tree/master/android/SherpaOnnxJavaDemo

JitPack is configured in settings.gradle (Groovy DSL):

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
        maven { url 'https://jitpack.io' }
    }
}

The dependency in app/build.gradle:

implementation 'com.github.k2-fsa.sherpa-onnx:sherpa-onnx:v1.13.5'

Download model files

Before building, download the model files into the assets directory:

# Assume we are inside the SherpaOnnxJavaDemo directory
cd app/src/main/assets/

wget https://github.com/k2-fsa/sherpa-onnx/releases/download/asr-models/sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20.tar.bz2

tar xvf sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20.tar.bz2
rm sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20.tar.bz2

mv sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/encoder-epoch-99-avg-1.int8.onnx ./
mv sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/decoder-epoch-99-avg-1.onnx ./
mv sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/joiner-epoch-99-avg-1.int8.onnx ./
mv sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/tokens.txt ./

rm -rf sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/*

mv encoder-epoch-99-avg-1.int8.onnx sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/
mv decoder-epoch-99-avg-1.onnx sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/
mv joiner-epoch-99-avg-1.int8.onnx sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/
mv tokens.txt sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20/

You should have the following directory structure:

app/src/main/assets/
└── sherpa-onnx-streaming-zipformer-bilingual-zh-en-2023-02-20
    ├── decoder-epoch-99-avg-1.onnx
    ├── encoder-epoch-99-avg-1.int8.onnx
    ├── joiner-epoch-99-avg-1.int8.onnx
    └── tokens.txt

1 directory, 4 files

Remember to remove unused files to reduce the file size of the final APK.

Build and run

Open the project in Android Studio, or build from the command line:

cd android/SherpaOnnxJavaDemo
./gradlew assembleDebug

Install the APK on your device:

adb install app/build/outputs/apk/debug/app-debug.apk

Demo 2: SherpaOnnxSimulateStreamingAsrWearOs (Kotlin DSL)

A Kotlin/Compose-based Wear OS demo that simulates streaming ASR.

https://github.com/k2-fsa/sherpa-onnx/tree/master/android/SherpaOnnxSimulateStreamingAsrWearOs

JitPack is configured in settings.gradle.kts (Kotlin DSL):

dependencyResolutionManagement {
    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
    repositories {
        google()
        mavenCentral()
        maven { url = uri("https://jitpack.io") }
    }
}

The dependency in app/build.gradle.kts:

implementation("com.github.k2-fsa.sherpa-onnx:sherpa-onnx:v1.13.5")

Build and run

cd android/SherpaOnnxSimulateStreamingAsrWearOs
./gradlew assembleDebug

Install the APK on your Wear OS device:

adb install app/build/outputs/apk/debug/app-debug.apk