> Audio Watermarks: Turn this on to embed a user's personal information into the audio as an inaudible watermark if they record during a meeting. If the audio file is shared without permission, Zoom can help identify which participant recorded the meeting.
Movie studios have done watermarking in the past with DVD screeners. Color laser printers output almost-invible patterns of yellow dots to match a document to a printer. When you download an academic paper as PDF, the PDF generally imprints the IP address and time of the downloader. Watermarking is nothing new.
For a company or government worried about employees leaking sensitive information to the press, this is an intriguing feature.
And if you're a determined whistleblower, this isn't going to stop you anyways.
The most extreme example is a secret that if I shared with you, I'd die painfully. You can't threaten me with death or torture because that's what's going to happen to me if I share it with you.
I say this regretfully because I really like the slogan "technology that allows you to say no to things is great", and, of course, it's not what you meant; but, taken to its extreme, the combination of this paragraph with the logic from your first paragraph:
> This is a fantastic feature … technology that allows you to say no to things is great.
means that an imaginary Zoom feature by which it would kill you painfully if you leaked sensitive data would be fantastic.
here's some old (ugly) code - quite short as you can see:
- encoding: https://github.com/jcelerier/libaudiotool/blob/master/src/li...
- decoding: https://github.com/jcelerier/libaudiotool/blob/master/src/li...
It would be interesting if they found a way to watermark the audio in such a way that removing the mark makes the audio unusable.
A common technique is to add pseudo noise to encode data over the whole audio spectrum. It's related to the spread spectrum techniques used for radio communications resistant to signal degradation (natural or jamming), common in many radio protocols, like your GPS receiver in your phone.
AFAIK these are just used to identify the streaming / download source (e.g. Spotify / TIDAL / Qobuz etc.), rather than the individual user as will be the case with Zoom. It'll be interesting to see what, if anything, has changed with the technology.
One day there was an Ars Technica article leaking some news, included a screenshot of RetailMe. I put the screenshot into Photoshop and low and behold there was the employee's ID.
I’m not defending (or denouncing, for that matter) this feature, though I have opinions.
If a watermarked audio is leaked, the owner of the account will be liable. If he shared he's zoom credentials, is just as bad as sharing the recording.