[Android 11] Crash on app start

[aca-info]

Hello,

Thank you for forking this project. I wanted to test the audio stream to an airport express but the application is crashing as soon as I launch it. I'm using the v0.5.0 on a Pocophone F1 on Android 11. The exception says that it needs android.permission.FOREGROUND_SERVICE.

Can you help me ?

[warren-bank]

That was a dumb oversight on my part.. thanks for letting me know; I'll add the permission today.. along with a minor release.

Funny that when I tested the app in Android 8.. it didn't crash with this exception.

However, regarding audio..

• the upstream app doesn't support playback of audio
• this fork treats audio files the same as video files.. by streaming the URL of the locally hosted audio file to the "/play" AirPlay endpoint
  • AirPlay v1 does not support playing audio streams in this way
  • AirTunes v1 uses RTSP streams, which is not something I have any intention to implement
  • it will (most likely) only work on ExoAirPlayer receiver
  • which is the only receiver that I can test.. and (to be perfectly honest) have any interest in supporting

[warren-bank]

PS: there are other apps out there that specifically implement AirTunes v1..

• I haven't tested any of them..
• but that's where you're most likely to find a successful outcome using real (but outdated) Apple hardware

PPS: actually, you can ignore that last comment..

• those apps are implementations of AirTunes v1 receivers..
  • which isn't what you want
  • since you already own a real one
• there are almost certainly AirTunes v1 senders/clients..
  • but I haven't done any searching to find good implementations
  • maybe if we do stumble across a good one, I could borrow some of its code and support real audio streams in this app
  • with an option to switch between RTSP audio and ExoAirPlayer supported audio
  • but unlikely to happen

PPPS: this is interesting..

• I tested sending audio files from Toaster Cast Android app to ExoAirPlayer receiver
  • didn't expect it to work, because I would expect that this app would use RTSP to stream the audio
  • what's interesting.. and good for me.. but bad for you.. is that this completely separate/unaffiliated app sends audio the exact same way as my client app
  • using the "/play" AirPlay v1 endpoint
  • which is perfectly compatible with ExoAirPlayer
  • but (most likely) won't work with your Apple hardware
    • maybe it will.. I honestly don't know.. and can't test

[warren-bank]

v0.5.1 release adds some missing permissions.. so you should now be able to test the client app and see what (if anything) happens on your airport express receiver.

[aca-info]

Wow ! Thank you very much for the release and your fast answer. :)

I'm not a fan of Apple but I was using the airport as a cheap DAC to stream some audio into a very old HK amplifier. On linux, I was using this so I think you're right about the RTSP audio. The only app that works so far on Android is this one. But unfortunately it's not open source and only a trial... I didn't know about Toaster Cast maybe it will work for me also.

There's no crash on the new release anymore but I'm stuck with "No services found". Maybe it can't detect airport receiver ?

[aca-info]

I've also found this repo and this one which seems to have an Airtunes player implementation. I will try to look both this weekend.

[warren-bank]

I completely forgot about AirMusic..

• when I looked at your link, it looked really really familiar
• then I remembered that I'd already played around with it and had it installed on my phone
• not that I have any use for it.. but you're right.. it looks like it does a great job (for its purpose)

I took only a super fast browse through this repo so far..

• the package name "com.grandstream.cast" doesn't have any Google search results
• based on the other apps jammed into this same repo, I'm guessing this isn't the original author.. but I can't find any copies of this app elsewhere
  • how in the world did you find this? :)
• it looks like it's running Bonjour services for discovery, and netty HTTP servers as a receiver..
  • I'm thinking the easiest way to see what it actually does.. is to just build the thing and run it
  • any interest in a copy of the APK when I do?

[warren-bank]

wait wait wait.. your 2nd repo.. this one is most definitely client code.. and it looks good!

PS: the upstream repo is ahead by a PR

interesting comment from the developer about its current state and audio format limitations. It currently only supports .wav files.. there's no built-in transcoders to convert other audio formats to .wav before streaming. I'd want to refer to the AirTunes v1 spec.. to see what it has to say about this.

[warren-bank]

spec says.. supported audio codecs are:

• PCM
• Apple Lossless (ALAC)
• AAC
• AAC ELD (Enhanced Low Delay)

discussion on SO says.. WAV is a container format that 99.9% of the time contains PCM data (following a mandatory header).

[warren-bank]

this blog has a great tutorial that outlines how to transcode audio files in any format that is natively supported by Android.. to PCM

rather than writing the PCM buffers to an AudioTrack.. it would be written to the RTSP stream

touch points:

• code:

  private FileInputStream input = null;

• code:

  public void setAudioInput(String path) throws FileNotFoundException {
    input = new FileInputStream(path);
    currentPos = 0;
  }

[warren-bank]

Before making any improvements to the "Peeler" app.. I'm curious if its basic functionality works.

I forked it and built an APK.. would you be willing to test it? ..remember, this version only supports WAV files.

[aca-info]

how in the world did you find this? :)

By searching in the depths of github ^^ (Really just using "airplay/airport express android" search terms and focusing on code instead of repositories)

any interest in a copy of the APK when I do?

Of course, I can to test it.

Concerning Peeler, that's some great news ! :) I installed the apk but no luck so far, the "Devices" tab is not showing any receiver and there's nothing in the logs...

[warren-bank]

Hmm.. that's not encouraging.

If this client could discover your receiver and play PCM from an audio file, then I'd be willing to tinker with it. But since it apparently needs much more work.. I apologize, but I'm out.

[aca-info]

No problem I understand. I'll try it myself. Thank you for all the information. :)