5 ms·

Most dystopic feature: > Audio Watermarks: Turn this on to embed a user's personal information into the audio as an inaudible watermark if they record during a

Most dystopic feature: > 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.

elldoubleyew 6y ago
I wonder how they are doing this. Wouldn't a low quality recording render this fingerprint invisible?
- diebeforei485 6y ago
  I'd love to see some analysis of what's going on as well. I assume this would work better for audio recorded on-device (eg. using screen capture software) than audio recorded externally after being played out on the speaker.
- grenoire 6y ago
  I wonder if it can be filtered out, on the other hand. Does anybody have knowledge on audio fingerprinting/watermarking? Or is it perhaps security theater?
  - jcelerier 6y ago
    most common technique is a spectral encoding, which can be quite resistant to degradation. here's some old (ugly) code - quite short as you can see: - encoding: https://github.com/jcelerier/libaudiotool/blob/master/src/libwatermark/watermark/SSWEncode.h#L43 https://github.com/jcelerier/libaudiotool/blob/master/src/li... - decoding: https://github.com/jcelerier/libaudiotool/blob/master/src/libwatermark/watermark/SSWDecode.h#L46 https://github.com/jcelerier/libaudiotool/blob/master/src/li...
  - banger180 6y ago
    My Guess is that it is mostly a security through obscurity thing for now, we do not know exactly how they mark the audio. When someone figures this out I believe that it should be possible to filter this out. 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.
    - slezyr 6y ago
      Just compare two records from two different users.
  - eigenvector 6y ago
    If the watermark is inaudible, can't it removed by re-encoding the audio with a bandpass filter tuned for audible range?
    - ithkuil 6y ago
      Inaudible just means that a person can't perceive it, not necessarily because it's outside the frequency range a human ear can sense. 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. https://en.m.wikipedia.org/wiki/Audio_watermark https://en.m.wikipedia.org/wiki/Audio_watermark
  - lozf 6y ago
    Streaming and downloaded audio from Universal Music Group, and some Sony releases has been "inaudibly watermarked" for some years now, but there are several cases of people complaining that the watermark is actually audible in their supposedly lossless FLAC/ALAC/WAV download. 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.
logicandreason 6y ago
*help identify the participant's account, but not the actual participant.
- qubex 6y ago
  That’s not much of a leap, though: if you know you were talking to some people, and then audio is leaked, then you can figure out which account did it. I’m not defending (or denouncing, for that matter) this feature, though I have opinions.
- WhyNotHugo 6y ago
  I guess this is targeted at corporate users. 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.
ktpsns 6y ago
This is really a terrible feature for anybody who doesn't like DRM. I only can hope clever hackers will identify these steganographic features in video and audio recordings of zoom sessions.
- ilogik 6y ago
  what does this have to do with DRM?
crazygringo 6y ago
What's dystopic about it? 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.
Awtem 6y ago
Attention tracking ... Oh great... I'm sure we all have been waiting for more big brother features like this one
ArlenBales 6y ago
Many game developers do this for any kind of NDA-enforced testing. Not necessarily to the audio but to the video.
- madeofpalk 6y ago
  Apple Retail has/had an internal communications iPad app called RetailMe that overlayed their employee number in a massive watermark on the screen to capture people to leak screenshots. It was slightly visible under normal use, but load it into photoshop and play with the curves and becomes super visible. 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.
renewiltord 6y ago
This is a fantastic feature. It isn't so much for the company to prevent it but a way for the guy being pressured to share the recording to say "I'm sorry, I can't. They embed details in it that if they were leaked would ruin me." i.e. technology that allows you to say no to things is great. 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.
- JadeNB 6y ago
  > 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.
  - renewiltord 6y ago
    Haha, right, that is the natural syllogism that one would arrive at. The missing pieces of the picture are the prior probabilities of accidental leaking vs. coerced leaking and the value of the individual. For a spy in danger of being exposed, yes, technology which guaranteed violent death on exposure would be fantastically desirable. I won't condescend to you by walking through the entire thing, but I think you can tell I'm not an extremist and have left out all the bits about the ROI etc.
  - hootguy 6y ago
    v6?
MR4D 6y ago
For companies in healthcare and finance, this is a good feature to protect clients.
derision 6y ago
Printers have done this for decades
vikramkr 6y ago
Dystopic? That's a privacy forward feature. Accountability to protect the privacy of meetings.
robbyt 6y ago
Apply some time stretch, pitch shift, slight distortion, and the watermark is likely destroyed.

elldoubleyew 6y ago

I wonder how they are doing this. Wouldn't a low quality recording render this fingerprint invisible?

diebeforei485 6y ago
I'd love to see some analysis of what's going on as well. I assume this would work better for audio recorded on-device (eg. using screen capture software) than audio recorded externally after being played out on the speaker.
grenoire 6y ago
I wonder if it can be filtered out, on the other hand. Does anybody have knowledge on audio fingerprinting/watermarking? Or is it perhaps security theater?
- jcelerier 6y ago
  most common technique is a spectral encoding, which can be quite resistant to degradation. here's some old (ugly) code - quite short as you can see: - encoding: https://github.com/jcelerier/libaudiotool/blob/master/src/libwatermark/watermark/SSWEncode.h#L43 https://github.com/jcelerier/libaudiotool/blob/master/src/li... - decoding: https://github.com/jcelerier/libaudiotool/blob/master/src/libwatermark/watermark/SSWDecode.h#L46 https://github.com/jcelerier/libaudiotool/blob/master/src/li...
- banger180 6y ago
  My Guess is that it is mostly a security through obscurity thing for now, we do not know exactly how they mark the audio. When someone figures this out I believe that it should be possible to filter this out. 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.
  - slezyr 6y ago
    Just compare two records from two different users.
- eigenvector 6y ago
  If the watermark is inaudible, can't it removed by re-encoding the audio with a bandpass filter tuned for audible range?
  - ithkuil 6y ago
    Inaudible just means that a person can't perceive it, not necessarily because it's outside the frequency range a human ear can sense. 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. https://en.m.wikipedia.org/wiki/Audio_watermark https://en.m.wikipedia.org/wiki/Audio_watermark
- lozf 6y ago
  Streaming and downloaded audio from Universal Music Group, and some Sony releases has been "inaudibly watermarked" for some years now, but there are several cases of people complaining that the watermark is actually audible in their supposedly lossless FLAC/ALAC/WAV download. 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.

logicandreason 6y ago

*help identify the participant's account, but not the actual participant.

qubex 6y ago
That’s not much of a leap, though: if you know you were talking to some people, and then audio is leaked, then you can figure out which account did it. I’m not defending (or denouncing, for that matter) this feature, though I have opinions.
WhyNotHugo 6y ago
I guess this is targeted at corporate users. 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.

ktpsns 6y ago

This is really a terrible feature for anybody who doesn't like DRM. I only can hope clever hackers will identify these steganographic features in video and audio recordings of zoom sessions.

ilogik 6y ago
what does this have to do with DRM?

crazygringo 6y ago

What's dystopic about it? 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.

Awtem 6y ago

Attention tracking ... Oh great... I'm sure we all have been waiting for more big brother features like this one

ArlenBales 6y ago

Many game developers do this for any kind of NDA-enforced testing. Not necessarily to the audio but to the video.

madeofpalk 6y ago
Apple Retail has/had an internal communications iPad app called RetailMe that overlayed their employee number in a massive watermark on the screen to capture people to leak screenshots. It was slightly visible under normal use, but load it into photoshop and play with the curves and becomes super visible. 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.

renewiltord 6y ago

This is a fantastic feature. It isn't so much for the company to prevent it but a way for the guy being pressured to share the recording to say "I'm sorry, I can't. They embed details in it that if they were leaked would ruin me." i.e. technology that allows you to say no to things is great. 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.

JadeNB 6y ago
> 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.
- renewiltord 6y ago
  Haha, right, that is the natural syllogism that one would arrive at. The missing pieces of the picture are the prior probabilities of accidental leaking vs. coerced leaking and the value of the individual. For a spy in danger of being exposed, yes, technology which guaranteed violent death on exposure would be fantastically desirable. I won't condescend to you by walking through the entire thing, but I think you can tell I'm not an extremist and have left out all the bits about the ROI etc.
- hootguy 6y ago
  v6?

MR4D 6y ago

For companies in healthcare and finance, this is a good feature to protect clients.

derision 6y ago

Printers have done this for decades

vikramkr 6y ago

Dystopic? That's a privacy forward feature. Accountability to protect the privacy of meetings.

robbyt 6y ago

Apply some time stretch, pitch shift, slight distortion, and the watermark is likely destroyed.