LDAC support?

[dagbdagb]

Seeing how aptX/aptX-HD may become a reality, I wanted to point at the even better(?) LDAC codec, which appears to be available under the apache license:

git clone https://android.googlesource.com/platform/external/libldac

[arkq]

Yes, why not. However, I've got no headset and/or audio source for testing LDAC.

[gpatounas]

+1

[arkq]

If anyone has a device (source or sink) with LDAC support and is willing to help during development (mostly testing), please let me know in the comment below or directly to me (via email). Otherwise, LDAC support in bluez-alsa will be possible only if someone provides pull request :)

[akatrevorjay]

@arkq I have an LDAP source (pixel2xl) and sink (sony headphones) and I'd love to help!

[akatrevorjay]

I have latest master with ldac support merged in, I'll test it out in a sec.

[dagbdagb]

@akatrevorjay
Great! I have tested the feature with Arkq the last week, but no success so far. Next step is getting a BT dump from a phone talking to an LDAC sink.
Have you enabled developer options on your phone? Can you try the Bluetooth HCI log feature to see if you can get a log when connecting and playing back audio from the 2XL to the headphones?

https://www.google.at/search?q=bluetooth+hci+snoop+log

[arkq]

Hi @akatrevorjay

Like @dagbdagb said, we've been trying to make LDAC work for the last week but without success... If your phone allows generating HCI log, that might be a major breakdown in this work. You might also try to connect your phone with bluealsa (with PC) and try to get logs on the PC side, e.g:

• compile ldac branch of bluealsa with LDAC support
• run bluealsa as follows (might be as root): bluealsa -p a2dp-sink --a2dp-force-audio-cd
• run (as root) tcpdump -i bluetooth0 -w /tmp/bt.dump
• connect phone with PC (check in logs of bluealsa if LDAC Sink has been used)
• play some music (few seconds)
• done

Of course, we've been trying this procedure as well, however in the generated log there was no packets with audio transfer.... maybe your phone will send data.

[akatrevorjay]

My phone does in fact support that I believe. I can also snoop externally if needed, but I doubt that's much more useful than a device hci dump ;) Should have time this weekend, I'll post results here!