Assistant capability and reverse-engineering thereof about pbpctrl

[qzed]

Hi, sorry for the late reply. Somehow I forgot about this...

First off, I agree with you that the playback interruption is likely firmware based, I think you could probably try if that still works when it's not connected to an android device.

Regarding the AI assistant feature, I'm pretty sure it just forwards the microphone to the device somehow. There are some additional protocols beyond the maestro one (for controlling settings etc.), and I think that one of those is responsible for that. But I haven't looked into them at all yet, so I can't say which one or how exactly it works.

So for implementing something like that, I think we'd first need to figure out how the pixel app/android integration does that. Again, it's probably some kind of RFCOMM bluetooth protocol, so if we can figure that out, then I'm pretty sure we can make that work. IIRC I tried to figure out how the long-press-button event is being sent, but it's not via the maestro protocol.

The way I went for the maestro/settings stuff is by reverse engineering the pixelbuds apk, so something like that could work again. Unless it's somehow a deeper integration into android itself via some device-independent protocol.

I reckon they probably use NDK themselves, tapping into Android's bluetooth internals, and from the symbols & sniffing alone would it be possible to infer complete logic?

That should be possible as well, I think. If you can manage to make that work. I briefly tried some sniffing via wireshark but that didn't work out for me.