How to use

First import the modules import 'flutter_sound.dart

The SoundPlayerUI provides a Playback widget styled after the HTML 5 audio player.

The player displays a loading indicator and allows the user to pause/resume/skip via the progress bar.

You can also pause/resume the player via an api call to SoundPlayerUI's state using a GlobalKey.

The SoundPlayerUI widget allows you to playback audio from multiple sources:

• File

• Asset

• URL

MediaFormat

When using the SoundPlayerUI you MUST pass a Track that has been initialised with a supported MediaFormat.

The Widget needs to obtain the duration of the audio that it is play and that can only be done if we know the MediaFormat of the Widget.

If you pass a Track that wasn't constructed with a MediaFormat then a MediaFormatException will be thrown.

The MediaFormat must also be natively supported by the OS. See mediaformat.md for additional details on checking for a supported format.

Example:

Sounds uses as the primary method of handing around audio data.

You can also dynamically load a Track when the user clicks the 'Play' button on the SoundPlayerUI widget. This allows you to delay the decision on what Track is going to be played until the user clicks the 'Play' button.

SimpleRecorder

SimpleRecorder

This is a very simple example for Flutter Sound beginners, that shows how to record, and then playback a file.

This example is really basic.

The complete example source

streamLoop

streamLoop

streamLoop() is a very simple example which connect the FlutterSoundRecorder sink to the FlutterSoundPlayer Stream. Of course, we do not play to the loudspeaker to avoid a very unpleasant Larsen effect. this example does not use a new StreamController, but use directely foodStreamController from flutter_sound_player.dart.

The complete example source

• Flutter Sound user: your documentation is there

• The CHANGELOG file is here

Overview

Flutter Sound is a Flutter package allowing you to play and record audio for :

• Android

• iOS

• Flutter Web

Maybe, one day, we will be supported by Linux, Macos, and even (why not) Windows. But this is not top of our priorities.

Flutter Sound provides both a high level API and widgets for:

• play audio

• record audio

Flutter Sound can be used to play a beep from an asset all the way up to implementing a complete media player.

The API is designed so you can use the supplied widgets or roll your own.

Features

The Flutter Sound package includes the following features

• Play and Record flutter sound or music with various codecs.

• Play local or remote files specified by their URL.

• Play assets.

Changelog

You can find the

Documentation

The

License

Flutter Sound is copyrighted by Dooboolab (2018, 2019, 2020). Flutter Sound is released under a license with a copyleft clause: the LGPL-V3 license. This means that if you modify some of Flutter Sound code you must publish your modifications under the LGPL license too.

Help Maintenance

Flutter Sound is a fundamental building block needed by almost every flutter project.

I'm looking to make Flutter Sound the go to project for Flutter Audio with support for each of the Flutter supported platforms.

Flutter Sound is a large and complex project which requires me to maintain multiple hardware platforms and test environments.

We greatly appreciate any contributions to the project which can be as simple as providing feedback on the API or documentation.

My friend Hyo has been maintaining quite many repos these days and he is burning out slowly. If you could help him cheer up, buy him a cup of coffee will make his life really happy and get much energy out of it. As a side effect, we will know that Flutter Sound is important for you, that you appreciate our job and that you can show it with a little money.

The τ (tau) Project is a set of libraries which deal with audio :

• A player for audio playback

• A recorder for recording audio

• Several utilities to handle audio files

Overview

τ is a library package allowing you to play and record audio for

• iOS

• Android

• Web

τ provides both a high level API and widgets for:

• play audio

• record audio

τ can be used to play a beep from an asset all the way up to implementing a complete media player.

The API is designed so you can use the supplied widgets or roll your own.

The τ package supports playback from:

• Assets

• Files

• URL

Features

The τ package includes the following features :

• Play and Record τ or music with various codecs. (See )

• Play local or remote files specified by their URL.

• Play assets.

Supported platforms

τ is actually supported by the following frameworks:

• Flutter (Flutter Sound)

In the future, it will be (perhaps) supported by

• React Native (Tau React). (Not yet. Later).

• Cordova (Tau Cordova). (Not yet. Later).

• Others (Native Script, Solar 2D, ...)

Supported targets

τ is actually supported by the following OS :

• iOS

• Android

• Web

In the future, it will be (perhaps) supported by

• Linux

• others (Windows, MacOS)

What about Flutter Sound ?

We just changed the name of the project, because we want to encompass others frameworks than Flutter.

We need help

τ is a fundamental building block needed by almost every mobile project.

We are looking to make τ the go to project for mobile Audio with support for various platforms and various OS.

τ is a large and complex project which requires to maintain multiple hardware platforms and test environments.

setAudioFocus()

• Dart API: setAudioFocus.

focus: parameter possible values are

• AudioFocus.requestFocus (request focus, but do not do anything special with others App)

• AudioFocus.requestFocusAndStopOthers (your app will have exclusive use of the output audio)

• AudioFocus.requestFocusAndDuckOthers (if another App like Spotify use the output audio, its volume will be lowered)

Other parameters :

Please look to to understand the meaning of the other parameters

Example:

</div>

setUIProgressBar()

• Dart API: setUIProgressBar().

This verb is used if the App wants to control itself the Progress Bar on the lock screen. By default, this progress bar is handled automaticaly by Flutter Sound. Remark setUIProgressBar() is implemented only on iOS.

Example:

</div>

pausePlayer()

• Dart API: pausePlayer().

Use this verbe to pause the current playback. An exception is thrown if the player is not in the "playing" state.

Example:

</div>

resumePlayer()

• Dart API: resumePlayer().

Use this verbe to resume the current playback. An exception is thrown if the player is not in the "paused" state.

Example:

</div>

nowPlaying()

• Dart API: nowPlaying().

This verb is used to set the Lock screen fields without starting a new playback. The fields 'dataBuffer' and 'trackPath' of the Track parameter are not used. Please refer to 'startPlayerFromTrack' for the meaning of the others parameters. Remark setUIProgressBar() is implemented only on iOS.

Example:

</div>

seekToPlayer()

• Dart API: seekToPlayer().

To seek to a new location. The player must already be playing or paused. If not, an exception is thrown.

Example:

</div>

foodSink

• Dart API: .

The sink side of the Food Controller that you use when you want to play asynchronously live data. This StreamSink accept two kinds of objects :

onProgress

• Dart API: onProgress.

The stream side of the Food Controller : this is a stream on which FlutterSound will post the player progression. You may listen to this Stream to have feedback on the current playback.

PlaybackDisposition has two fields :

• Duration duration (the total playback duration)

• Duration position (the current playback position)

Example:

</div>

isDecoderSupported()

• Dart API: isDecoderSupported().

This verb is useful to know if a particular codec is supported on the current platform. Returns a Future.

Example:

</div>

startPlayer()

• Dart API: startPlayer().

You can use startPlayer to play a sound.

• startPlayer() has three optional parameters, depending on your sound source :

  • fromUri: (if you want to play a file or a remote URI)

You must specify one or the three parameters : fromUri, fromDataBuffer, fromStream.

• You use the optional parametercodec: for specifying the audio and file format of the file. Please refer to the to know which codecs are currently supported.

• whenFinished:() : A lambda function for specifying what to do when the playback will be finished.

Very often, the codec: parameter is not useful. Flutter Sound will adapt itself depending on the real format of the file provided. But this parameter is necessary when Flutter Sound must do format conversion (for example to play opusOGG on iOS).

startPlayer() returns a Duration Future, which is the record duration.

Hint: can be useful if you want to get access to some directories on your device.

Example:

</div>

Example:

</div>

getProgress()

• Dart API: getProgress().

This verb is used to get the current progress of a playback. It returns a Map with two Duration entries : 'progress' and 'duration'. Remark : actually only implemented on iOS.

Example:

</div>

Creating the Player instance.

• Dart API: constructor.

This is the first thing to do, if you want to deal with playbacks. The instanciation of a new player does not do many thing. You are safe if you put this instanciation inside a global or instance variable initialization.

Example:

</div>

stopPlayer()

• Dart API: .

Use this verb to stop a playback. This verb never throw any exception. It is safe to call it everywhere, for example when the App is not sure of the current Audio State and want to recover a clean reset state.

startPlayerFromTrack()

• Dart API: startPlayerFromTrack().

Use this verb to play data from a track specification and display controls on the lock screen or an Apple Watch. The Audio Session must have been open with the parameter withUI.

• track parameter is a simple structure which describe the sound to play. Please see

• whenFinished:() : A function for specifying what to do when the playback will be finished.

• onPaused:()

startPlayerFromTrack() returns a Duration Future, which is the record duration.

Example:

</div>

Food

• Dart API: food.

• Dart API: .

• Dart API: .

This are the objects that you can add to foodSink The Food class has two others inherited classes :

• FoodData (the buffers that you want to play)

• FoodEvent (a call back to be called after a resynchronisation)

Example:

shows how to play Live data, without Back Pressure from Flutter Sound

</div>

setSubscriptionDuration()

• Dart API: setSubscriptionDuration().

This verb is used to change the default interval between two post on the "Update Progress" stream. (The default interval is 0 (zero) which means "NO post")

Example:

</div>

setVolume()

• Dart API: setVolume().

The parameter is a floating point number between 0 and 1. Volume can be changed when player is running. Manage this after player starts.

Example:

</div>

Module instanciation

• Dart API: constructor

You do not need to instanciate the Flutter Sound Helper module. To use this module, you can just use the singleton offers by the module : flutterSoundHelper.

Example:

</div>

setSubscriptionDuration()

• Dart API: setSubscriptionDuration

This verb is used to change the default interval between two post on the "Update Progress" stream. (The default interval is 0 (zero) which means "NO post")

Example:

</div>

resumeRecorder()

• Dart API: resumeRecorder

On Android this API verb needs al least SDK-24. An exception is thrown if the Recorder is not currently paused.

Example:

</div>

openAudioSession() and closeAudioSession()

• Dart API: openAudioSession.

• Dart API: .

A player must be opened before used. A player correspond to an Audio Session. With other words, you must open the Audio Session before using it. When you have finished with a Player, you must close it. With other words, you must close your Audio Session. Opening a player takes resources inside the OS. Those resources are freed with the verb closeAudioSession(). It is safe to call this procedure at any time.

• If the Player is not open, this verb will do nothing

• If the Player is currently in play or pause mode, it will be stopped before.

focus: parameter

focus is an optional parameter can be specified during the opening : the Audio Focus. This parameter can have the following values :

• AudioFocus.requestFocusAndStopOthers (your app will have exclusive use of the output audio)

• AudioFocus.requestFocusAndDuckOthers (if another App like Spotify use the output audio, its volume will be lowered)

• AudioFocus.requestFocusAndKeepOthers (your App will play sound above others App)

The Audio Focus is abandoned when you close your player. If your App must play several sounds, you will probably open your player just once, and close it when you have finished with the last sound. If you close and reopen an Audio Session for each sound, you will probably get unpleasant things for the ears with the Audio Focus.

category

category is an optional parameter used only on iOS. This parameter can have the following values :

• ambient

• multiRoute

• playAndRecord

See to understand the meaning of this parameter.

mode

mode is an optional parameter used only on iOS. This parameter can have the following values :

• modeDefault

• modeGameChat

• modeMeasurement

See to understand the meaning of this parameter.

audioFlags

are a set of optional flags (used on iOS):

• outputToSpeaker

• allowHeadset

• allowEarPiece

device

is the output device (used on Android)

• speaker

• headset,

• earPiece,

withUI

is a boolean that you set to true if you want to control your App from the lock-screen (using during your Audio Session).

You MUST ensure that the player has been closed when your widget is detached from the UI. Overload your widget's dispose() method to closeAudioSession the player when your widget is disposed. In this way you will reset the player and clean up the device resources, but the player will be no longer usable.

You may not open many Audio Sessions without closing them. You will be very bad if you try something like :

openAudioSession() and closeAudioSession() return Futures. You may not use your Player before the end of the initialization. So probably you will await the result of openAudioSession(). This result is the Player itself, so that you can collapse instanciation and initialization together with myPlayer = await FlutterSoundPlayer().openAudioSession();

Example:

</div>

feedFromStream()

• Dart API: feedFromStream().

This is the verb that you use when you want to play live PCM data synchronously. This procedure returns a Future. It is very important that you wait that this Future is completed before trying to play another buffer.

Example:

• shows how to play Live data, with Back Pressure from Flutter Sound

• shows how to play some real time sound effects synchronously.

</div>

-

setAudioFocus()

• Dart API:

focus: parameter possible values are

• AudioFocus.requestFocus (request focus, but do not do anything special with others App)

• AudioFocus.requestFocusAndStopOthers (your app will have exclusive use of the output audio)

• AudioFocus.requestFocusAndDuckOthers (if another App like Spotify use the output audio, its volume will be lowered)

Other parameters :

Please look to to understand the meaning of the other parameters

Example:

</div>

playerState, isPlaying, isPaused, isStopped. getPlayerState()

• Dart API: .

• Dart API: .

• Dart API: .

• Dart API: .

• Dart API: .

This four verbs is used when the app wants to get the current Audio State of the player.

playerState is an attribut which can have the following values :

• isStopped /// Player is stopped

• isPlaying /// Player is playing

• isPaused /// Player is paused

Flutter Sound shows in the playerState attribut the last known state. When the Audio State of the background OS engine changes, the playerState parameter is not updated exactly at the same time. If you want the exact background OS engine state you must use PlayerState theState = await myPlayer.getPlayerState(). Acutually getPlayerState() is only implemented on iOS.

Example:

</div>

startPlayerFromStream()

• Dart API: startPlayerFromStream().

This functionnality needs, at least, and Android SDK >= 21

• The only codec supported is actually Codec.pcm16.

• The only value possible for numChannels is actually 1.

• SampleRate is the sample rate of the data you want to play.

Please look to

Example You can look to the three provided examples :

• shows how to play Live data, with Back Pressure from Flutter Sound

• shows how to play Live data, without Back Pressure from Flutter Sound

• shows how to play some real time sound effects.

Example 1:

</div>

Example 2:

</div>

recorderState, isRecording, isPaused, isStopped

• Dart API:

• Dart API:

• Dart API:

• Dart API:

This four attributs is used when the app wants to get the current Audio State of the recorder.

recorderState is an attribut which can have the following values :

• isStopped /// Recorder is stopped

• isRecording /// Recorder is recording

• isPaused /// Recorder is paused

Example:

</div>

onProgress

• Dart API: onProgress

The attribut onProgress is a stream on which FlutterSound will post the recorder progression. You may listen to this Stream to have feedback on the current recording.

Example:

</div>

startRecorder()

• Dart API: startRecorder

You use startRecorder() to start recording in an open session. startRecorder() has the destination file path as parameter. It has also 7 optional parameters to specify :

• codec: The codec to be used. Please refer to the to know which codecs are currently supported.

• toFile: a path to the file being recorded

• toStream: if you want to record to a Dart Stream. Please look to . This new functionnality needs, at least, Android SDK >= 21 (23 is better)

can be useful if you want to get access to some directories on your device.

Flutter Sound does not take care of the recording permission. It is the App responsability to check or require the Recording permission. is probably useful to do that.

Example:

</div>

pauseRecorder()

• Dart API: pauseRecorder

On Android this API verb needs al least SDK-24. An exception is thrown if the Recorder is not currently recording.

Example:

</div>

isEncoderSupported()

• Dart API: isEncoderSupported

This verb is useful to know if a particular codec is supported on the current platform; Return a Future.

Example:

</div>

waveToPCMBuffer()

• Dart API: waveToPCMBuffer()

This verb is usefull to convert a Wave buffer to a Raw PCM buffer. Note that this verb is not asynchronous and does not return a Future.

It removes the Wave envelop from the PCM buffer.

Example:

</div>

waveToPCM()

• Dart API: waveToPCM()

This verb is usefull to convert a Wave file to a Raw PCM file.

It removes the Wave envelop from the PCM file.

Example:

</div>

isFFmpegAvailable()

• Dart API: isFFmpegAvailable()

This verb is used to know during runtime if FFmpeg is linked with the App.

Example:

</div>

openAudioSession() and closeAudioSession()

• Dart API: openAudioSession

• Dart API:

A recorder must be opened before used. A recorder correspond to an Audio Session. With other words, you must open the Audio Session before using it. When you have finished with a Recorder, you must close it. With other words, you must close your Audio Session. Opening a recorder takes resources inside the OS. Those resources are freed with the verb closeAudioSession().

You MUST ensure that the recorder has been closed when your widget is detached from the UI. Overload your widget's dispose() method to close the recorder when your widget is disposed. In this way you will reset the player and clean up the device resources, but the recorder will be no longer usable.

You maynot openAudioSession many recorders without releasing them. You will be very bad if you try something like :

openAudioSession() and closeAudioSession() return Futures. You may not use your Recorder before the end of the initialization. So probably you will await the result of openAudioSession(). This result is the Recorder itself, so that you can collapse instanciation and initialization together with myRecorder = await FlutterSoundPlayer().openAudioSession();

The four optional parameters are used if you want to control the Audio Focus. Please look to to understand the meaning of those parameters

Example:

</div>

duration()

• Dart API: duration()

This verb is used to get an estimation of the duration of a sound file. Be aware that it is just an estimation, based on the Codec used and the sample rate.

Note : this verb uses FFmpeg and is not available int the LITE flavor of Flutter Sound.

Example:

</div>

stopRecorder()

• Dart API: stopRecorder

Use this verb to stop a record. This verb never throws any exception. It is safe to call it everywhere, for example when the App is not sure of the current Audio State and want to recover a clean reset state.

Example:

</div>

pcmToWaveBuffer()

• Dart API: pcmToWaveBuffer()

This verb is usefull to convert a Raw PCM buffer to a Wave buffer.

It adds a Wave envelop in front of the PCM buffer, so that the file can be played back with startPlayerFromBuffer().

Note: the parameters numChannels and sampleRate are mandatory, and must match the actual PCM data. a discussion about Raw PCM and WAVE file format.

Example:

</div>

pcmToWave()

• Dart API: pcmToWave()

This verb is usefull to convert a Raw PCM file to a Wave file.

It adds a Wave envelop to the PCM file, so that the file can be played back with startPlayer().

Note: the parameters numChannels and sampleRate are mandatory, and must match the actual PCM data. a discussion about Raw PCM and WAVE file format.

Example:

</div>

getLastFFmpegCommandOutput()

• Dart API: getLastFFmpegCommandOutput()

This simple verb is used to get the output of the last FFmpeg command

Example:

</div>

getLastFFmpegReturnCode()

• Dart API:

executeFFmpegWithArguments()

• Dart API: executeFFmpegWithArguments()

This verb is a wrapper for the great FFmpeg application. The command "man ffmpeg" (if you have installed ffmpeg on your computer) will give you many informations. If you do not have ffmpeg on your computer you will find easyly on internet many documentation on this great program.

Example:

</div>

convertFile()

• Dart API: convertFile()

This verb is useful to convert a sound file to a new format.

• infile is the file path of the file you want to convert

• codecin is the actual file format

• outfile

Be careful : outfile and codecout must be compatible. The output file extension must be a correct file extension for the new format.

Note : this verb uses FFmpeg and is not available int the LITE flavor of Flutter Sound.

Example:

</div>

ffMpegGetMediaInformation()

• Dart API: ffMpegGetMediaInformation()

This verb is used to get various informations on a file.

The informations got with FFmpegGetMediaInformation() are .

Example:

</div>

How to use

First import the modules import 'flutter_sound.dart

The SoundPlayerUI provides a Playback widget styled after the HTML 5 audio player.

The player displays a loading indicator and allows the user to pause/resume/skip via the progress bar.

You can also pause/resume the player via an api call to SoundPlayerUI's state using a GlobalKey.

The SoundPlayerUI widget allows you to playback audio from multiple sources:

• File

• Asset

• URL

MediaFormat

When using the SoundPlayerUI you MUST pass a Track that has been initialised with a supported MediaFormat.

The Widget needs to obtain the duration of the audio that it is play and that can only be done if we know the MediaFormat of the Widget.

If you pass a Track that wasn't constructed with a MediaFormat then a MediaFormatException will be thrown.

The MediaFormat must also be natively supported by the OS. See mediaformat.md for additional details on checking for a supported format.

Example:

Sounds uses as the primary method of handing around audio data.

You can also dynamically load a Track when the user clicks the 'Play' button on the SoundPlayerUI widget. This allows you to delay the decision on what Track is going to be played until the user clicks the 'Play' button.

Module instanciation

Dart definition (prototype) :

You do not need to instanciate the Flutter Sound Helper module. To use this module, you can just use the singleton offers by the module : flutterSoundHelper.

Example:

convertFile()

Dart definition (prototype) :

This verb is useful to convert a sound file to a new format.

• infile is the file path of the file you want to convert

• codecin is the actual file format

• outfile

Be careful : outfile and codecout must be compatible. The output file extension must be a correct file extension for the new format.

Note : this verb uses FFmpeg and is not available int the LITE flavor of Flutter Sound.

Example:

pcmToWave()

Dart definition (prototype) :

This verb is usefull to convert a Raw PCM file to a Wave file.

It adds a Wave envelop to the PCM file, so that the file can be played back with startPlayer().

Note: the parameters numChannels and sampleRate are mandatory, and must match the actual PCM data. a discussion about Raw PCM and WAVE file format.

Example:

pcmToWaveBuffer()

Dart definition (prototype) :

This verb is usefull to convert a Raw PCM buffer to a Wave buffer.

It adds a Wave envelop in front of the PCM buffer, so that the file can be played back with startPlayerFromBuffer().

Note: the parameters numChannels and sampleRate are mandatory, and must match the actual PCM data. a discussion about Raw PCM and WAVE file format.

Example:

waveToPCM()

Dart definition (prototype) :

This verb is usefull to convert a Wave file to a Raw PCM file.

It removes the Wave envelop from the PCM file.

Example:

waveToPCMBuffer()

Dart definition (prototype) :

This verb is usefull to convert a Wave buffer to a Raw PCM buffer. Note that this verb is not asynchronous and does not return a Future.

It removes the Wave envelop from the PCM buffer.

Example:

duration()

Dart definition (prototype) :

This verb is used to get an estimation of the duration of a sound file. Be aware that it is just an estimation, based on the Codec used and the sample rate.

Note : this verb uses FFmpeg and is not available int the LITE flavor of Flutter Sound.

Example:

isFFmpegAvailable()

Dart definition (prototype) :

This verb is used to know during runtime if FFmpeg is linked with the App.

Example:

executeFFmpegWithArguments()

Dart definition (prototype) :

This verb is a wrapper for the great FFmpeg application. The command "man ffmpeg" (if you have installed ffmpeg on your computer) will give you many informations. If you do not have ffmpeg on your computer you will find easyly on internet many documentation on this great program.

Example:

getLastFFmpegReturnCode()

Dart definition (prototype) :

This simple verb is used to get the result of the last FFmpeg command

Example:

getLastFFmpegCommandOutput()

Dart definition (prototype) :

This simple verb is used to get the output of the last FFmpeg command

Example:

FFmpegGetMediaInformation

Dart definition (prototype) :

This verb is used to get various informations on a file.

The informations got with FFmpegGetMediaInformation() are .

Example:

How to use

First import the modules import 'flutter_sound.dart

The SoundPlayerUI provides a Playback widget styled after the HTML 5 audio player.

The player displays a loading indicator and allows the user to pause/resume/skip via the progress bar.

You can also pause/resume the player via an api call to SoundPlayerUI's state using a GlobalKey.

The SoundPlayerUI widget allows you to playback audio from multiple sources:

• File

• Asset

• URL

MediaFormat

When using the SoundPlayerUI you MUST pass a Track that has been initialised with a supported MediaFormat.

The Widget needs to obtain the duration of the audio that it is play and that can only be done if we know the MediaFormat of the Widget.

If you pass a Track that wasn't constructed with a MediaFormat then a MediaFormatException will be thrown.

The MediaFormat must also be natively supported by the OS. See mediaformat.md for additional details on checking for a supported format.

Example:

Sounds uses as the primary method of handing around audio data.

You can also dynamically load a Track when the user clicks the 'Play' button on the SoundPlayerUI widget. This allows you to delay the decision on what Track is going to be played until the user clicks the 'Play' button.

τ is composed with 4 modules :

• FlutterSoundPlayer, wich deal with everything about playbacks

• FlutterSoundRecorder, which deal with everything about recording

• FlutterSoundHelper, which offers some convenients tools

• FlutterSoundUI, which offer some Widget ready to be used out of the box

To use Flutter Sound you just do :

This will import all the necessaries dart interfaces.

Playback

1. Instance one ore more players. A good place to do that is in your init() function. It is also possible to instanciate the players "on the fly", when needed.

2. Open it. You cannot do anything on a close Player. An audio-session is then created.

3. Use the various verbs implemented by the players.

Recording

1. Instance your recorder. A good place to do that is in your init() function.

2. Open it. You cannot do anything on a close Recorder. An audio-session is then created.

3. Use the various verbs implemented by the players.

WidgetUIDemo

This is a Demo of an App which uses the Flutter Sound UI Widgets.

My own feeling is that this Demo is really too much complicated for doing something very simple. There is too many dependencies and too many sources.

Demo

Demo

This is a Demo of what it is possible to do with Flutter Sound. The code of this Demo app is not so simple and unfortunately not very clean :-( .

Flutter Sound beginners : you probably should look to SimplePlayback and SimpleRecorder

The biggest interest of this Demo is that it shows most of the features of Flutter Sound :

• Plays from various media with various codecs

• Records to various media with various codecs

• Pause and Resume control from recording or playback

It would be really great if someone rewrite this demo soon

The complete example source

SimplePlayback

SimplePlayback

This is a very simple example for Flutter Sound beginners, that shows how to play a remote file.

This example is really basic.

The complete example source

How to use

First import the modules import 'flutter_sound.dart

The SoundPlayerUI provides a Playback widget styled after the HTML 5 audio player.

The player displays a loading indicator and allows the user to pause/resume/skip via the progress bar.

You can also pause/resume the player via an api call to SoundPlayerUI's state using a GlobalKey.

The SoundPlayerUI widget allows you to playback audio from multiple sources:

• File

• Asset

• URL

MediaFormat

When using the SoundPlayerUI you MUST pass a Track that has been initialised with a supported MediaFormat.

The Widget needs to obtain the duration of the audio that it is play and that can only be done if we know the MediaFormat of the Widget.

If you pass a Track that wasn't constructed with a MediaFormat then a MediaFormatException will be thrown.

The MediaFormat must also be natively supported by the OS. See mediaformat.md for additional details on checking for a supported format.

Example:

Sounds uses as the primary method of handing around audio data.

You can also dynamically load a Track when the user clicks the 'Play' button on the SoundPlayerUI widget. This allows you to delay the decision on what Track is going to be played until the user clicks the 'Play' button.

•

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livePlaybackWithBackPressure

livePlaybackWithBackPressure

A very simple example showing how to play Live Data with back pressure. It feeds a live stream, waiting that the Futures are completed for each block.

This example get the data from an asset file, which is completely stupid : if an App wants to play an asset file he must use "StartPlayerFromBuffer().

If you do not need any back pressure, you can see another simple example : . This other example is a little bit simpler because the App does not need to await the playback for each block before playing another one.

The complete example source

livePlaybackWithoutBackPressure

livePlaybackWithoutBackPressure

A very simple example showing how to play Live Data without back pressure. It feeds a live stream, without waiting that the Futures are completed for each block. This is simpler than playing buffers synchronously because the App does not need to await that the playback for each block is completed playing another one.

This example get the data from an asset file, which is completely stupid : if an App wants to play a long asset file he must use .

Feeding Flutter Sound without back pressure is very simple but you can have two problems :

• If your App is too fast feeding the audio channel, it can have problems with the Stream memory used.

• The App does not have any knowledge of when the provided block is really played.

  For example, if it does a "stopPlayer()" it will loose all the buffered data.

This example uses the object to resynchronize the output stream before doing a

The complete example source

soundEffect

soundEffect

startPlayerFromStream can be very efficient to play sound effects in real time. For example in a game App. In this example, the App open the Audio Session and call startPlayerFromStream() during initialization. When it want to play a noise, it has just to call the synchronous verb feed. Very fast.

The complete example source

Playback

The complete running example is there

1. FlutterSoundPlayer instanciation

To play back something you must instanciate a player. Most of the time, you will need just one player, and you can place this instanciation in the variables initialisation of your class :

2. Open and close the audio session

Before calling startPlayer() you must open the Session.

When you have finished with it, you must close the session. A good places to put those verbs are in the procedures initState() and dispose().

3. Play your sound

To play a sound you call startPlayer(). To stop a sound you call stopPlayer()

Recording

The complete running example

1. FlutterSoundRecorder instanciation

To play back something you must instanciate a recorder. Most of the time, you will need just one recorder, and you can place this instanciation in the variables initialisation of your class :

2. Open and close the audio session

Before calling startRecorder() you must open the Session.

When you have finished with it, you must close the session. A god place to pute those verbs is in the procedures initState() and dispose().

3. Record something

To record something you call startRecorder(). To stop the recorder you call stopRecorder()

Install

For help on adding as a dependency, view the documentation.

Flutter Sound flavors

Flutter Sound comes in two flavors :

• the FULL flavor : flutter_sound

• the LITE flavor : flutter_sound_lite

The big difference between the two flavors is that the LITE flavor does not have mobile_ffmpeg embedded inside. There is a huge impact on the memory used, but the LITE flavor will not be able to do :

• Support some codecs like Playback OGG/OPUS on iOS or Record OGG_OPUS on iOS

• Will not be able to offer some helping functions, like FlutterSoundHelper.FFmpegGetMediaInformation() or FlutterSoundHelper.duration()

Here are the size of example/demo1 iOS .ipa in Released Mode. Those numbers include everything (flutter library, application, ...) and not only Flutter Sound.

Linking your App directly from pub.dev

Add flutter_sound or flutter_sound_lite as a dependency in pubspec.yaml.

The actual versions are :

• flutter_sound_lite: ^5.0.0 (the LTS version without FFmpeg)

• flutter_sound: ^5.0.0 (the LTS version with FFmpeg embedded)

• flutter_sound_lite: ^6.0.0 (the current version without FFmpeg)

or

Linking your App with Flutter Sound sources (optional)

The Flutter-Sound sources .

There is actually two branches :

• V5. This is the Long Term Support (LTS) branch which is maintained under the version 5.x.x

• master. This is the branch currently developed and is released under the version 6.x.x.

If you want to generate your App from the sources with a FULL flavor:

and add your dependency in your pubspec.yaml :

If you prefer to link your App with the LITE flavor :

and add your dependency in your pubspec.yaml :

FFmpeg

flutter_sound FULL flavor makes use of flutter_ffmpeg. In contrary to Flutter Sound Version 3.x.x, in Version 4.0.x your App can be built without any Flutter-FFmpeg dependency. flutter_ffmpeg audio-lts is now embedding inside the FULL flutter_sound.

If your App needs to use FFmpeg audio package, you must use the embedded version inside flutter_sound instead of adding a new dependency in your pubspec.yaml.

If your App needs an other FFmpeg package (for example the "video" package), use the LITE flavor of Flutter Sound and add yourself the App dependency that you need.

Post Installation

• On iOS you need to add usage descriptions to info.plist:

• On Android you need to add a permission to AndroidManifest.xml:

Flutter Web

To use Flutter Sound in a web application, you can either :

Static reference

Add those 4 lines at the end of the <head> section of your index.html file :

or Dynamic reference

Add those 4 lines at the end of the <head> section of your index.html file :

Please to understand how you can specify the interval of the versions you are interested by.

Troubles shooting

Problem with Cocoapods

If you get this message (specially after the release of a new Flutter Version) :

you can try the following instructions sequence (and ignore if some commands gives errors) :

If everything good, the last pod install must not give any error.