On Tue, Aug 9, 2016 at 11:06 PM, Daniel Hoffman via bitcoin-dev <
bitcoin-dev@lists.linuxfoundation.org> wrote:

> I have updated the GitHub a lot (changed tones to be less chirpy, fixed
> some smalls) and made a couple of samples (see attachment for MP3 and FLAC
> of both tone tables, first 16 then 4). Is this good enough to warrant an
> official BIP number? I haven't built a decoder yet, but it seems like the
> encoder is working properly (looked at Audacity, seems like it is working),
> and some people on reddit want to "allow for decoding experiments"
> <https://www.reddit.com/r/btc/comments/4wsn7v/bip_proposal_addresses_over_audio_thoughts/d69m3st>
>
> What suggestions do you all have for it?
>


With DSP hat on, your decoder for noisy/distorted channels will be 99.9% of
the complexity and will completely control the design of the encoder.

It's not a proposal yet without a decoder, it's just an idea.  FSK modems
microphone-channel (terrible multipath) is quite challenging and several
other parties have tried to do bitcoin info over audio in the past without
success.

It's very interesting, but I think you do need to go through and get the
whole thing working to really gauge viability.