README.md



tts

This example demonstrates how to use text to speech (TTS) in Flutter with sherpa-onnx.

It works on the following platforms:


Android
iOS
Linux
macOS (both arm64 and x86_64 are supported)
Windows


Screenshots are given below:


Android
iOS
Linux
macOS
Windows


How to build

Before you run flutter build, you have to select a TTS model and change
the code to use your selected model.


1. Select a TTS model

We have a list of TTS models at

https://github.com/k2-fsa/sherpa-onnx/releases/tag/tts-models

You can select any of them. If you feel that there are so many that you don't know
which one is the best, please visit http://huggingface.co/spaces/k2-fsa/text-to-speech
and try each one by yourself and select the one you consider the best.

Suppose you select

https://github.com/k2-fsa/sherpa-onnx/releases/download/tts-models/vits-piper-en_US-libritts_r-medium.tar.bz2

Then please do the following:


1. Download and unzip the model


cd flutter-examples/tts/assets
wget https://github.com/k2-fsa/sherpa-onnx/releases/download/tts-models/vits-piper-en_US-libritts_r-medium.tar.bz2
tar xf vits-piper-en_US-libritts_r-medium.tar.bz2
rm vits-piper-en_US-libritts_r-medium.tar.bz2
cd ..

./generate-asset-list.py


Note that you have to run ./generate-asset-list.py so that Flutter knows where
  to find the model.


Change the code to use the downloaded model.


We have given several examples for different models in ./lib/model.dart.
For our selected model, we need to change ./lib/model.dart so that it looks like below:


// Example 6
// https://github.com/k2-fsa/sherpa-onnx/releases/tag/tts-models
// https://github.com/k2-fsa/sherpa-onnx/releases/download/tts-models/vits-piper-en_US-libritts_r-medium.tar.bz2
modelDir = 'vits-piper-en_US-libritts_r-medium';
modelName = 'en_US-libritts_r-medium.onnx';
dataDir = 'vits-piper-en_US-libritts_r-medium/espeak-ng-data';


3. That's it.


Build the APP


1. For Linux


flutter build linux

# See below if you get any errors


2. For macOS


To build a universal2 APP, use

flutter build macos


To build for x86_64, use

export FLUTTER_XCODE_ARCHS=x86_64
flutter build macos


To build for arm64, use

export FLUTTER_XCODE_ARCHS=arm64
flutter build macos


3. For Windows


flutter build windows


4. For Android


flutter build apk --split-per-abi


5. For iOS


First, connect your iPhone to your computer and use flutter devices to show
available devices. You will see something like below:

Found 3 connected devices:
  iPhone (mobile) • 00008030-001064212E85802E • ios            • iOS 16.3 20D47
  macOS (desktop) • macos                     • darwin-x64     • macOS 13.1 22C65 darwin-x64
  Chrome (web)    • chrome                    • web-javascript • Google Chrome 126.0.6478.127

No wireless devices were found.

Run "flutter emulators" to list and start any available device emulators.

If you expected another device to be detected, please run "flutter doctor" to diagnose potential issues. You may also try increasing the time to wait for connected devices with the "--device-timeout" flag. Visit https://flutter.dev/setup/ for troubleshooting tips.


Then you can use

flutter run -d 00008030-001064212E85802E --release


You would see something like below:

Launching lib/main.dart on iPhone in release mode...
Automatically signing iOS for device deployment using specified development team in Xcode project: N5ZH3Z63A6
Running pod install...                                           1,773ms
Running Xcode build...
Xcode build done.                                            7.9s
Failed to build iOS app
Could not build the precompiled application for the device.
Error (Xcode): No profiles for 'com.k2fsa.sherpa.onnx.tts' were found: Xcode couldn't find any iOS App Development provisioning profiles matching
'com.k2fsa.sherpa.onnx.tts'. Automatic signing is disabled and unable to generate a profile. To enable automatic signing, pass
-allowProvisioningUpdates to xcodebuild.
/Users/fangjun/open-source/sherpa-onnx/flutter-examples/tts/ios/Runner.xcodeproj


It appears that there was a problem signing your application prior to installation on the device.

Verify that the Bundle Identifier in your project is your signing id in Xcode
  open ios/Runner.xcworkspace

Also try selecting 'Product > Build' to fix the problem.

Error running application on iPhone.


After you have followed the instructions in the above log, run gain


Note: I have run open ios/Runner.xcworkspace and click Product -> Build.


flutter run -d 00008030-001064212E85802E --release


Finally, it will show something like below:

Launching lib/main.dart on iPhone in release mode...
Automatically signing iOS for device deployment using specified development team in Xcode project: N5ZH3Z63A6
Running Xcode build...
 └─Compiling, linking and signing...                         6.5s
Xcode build done.                                           18.3s
Installing and launching...                                        22.9s

Flutter run key commands.
h List all available interactive commands.
c Clear the screen
q Quit (terminate the application on the device).


Fix for Linux

If you get the following errors on Linux,

Building Linux application...
CMake Error at /usr/local/share/cmake-3.29/Modules/FindPkgConfig.cmake:634 (message):
  The following required packages were not found:

   - gstreamer-1.0

Call Stack (most recent call first):
  /usr/local/share/cmake-3.29/Modules/FindPkgConfig.cmake:862 (_pkg_check_modules_internal)
  flutter/ephemeral/.plugin_symlinks/audioplayers_linux/linux/CMakeLists.txt:24 (pkg_check_modules)


please run:

sudo apt-get install -y libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libunwind-dev


See also https://github.com/bluefireteam/audioplayers/tree/main/packages/audioplayers_linux#setup-for-linux
for the above error.