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Video watermarking/tracking on CH videos

Posted: Sun Mar 21, 2021 9:48 pm
by torachan
Hey guys,

I'm working on a Foot fetish Cock Hero series and wondering how you have been dealing with possible watermarks/fingerprints in videos? I have a sample which I'd like to share but need to mitigate any risks before doing that. Many of the videos I'm using in the CH series have a warning label that say they use "fingerprints" that can include some personal information/identifiable information. Does anyone have experience overcoming these? Or are they simply scare tactics?

At least for me it feels like an overkill for porn distributors to create such a content delivery system where they can identify the user/person by embedding some hidden frame/metadata pixels in the video. But I'm not as confident on this topic so hopefully someone can give me some tips :)

Cheers!

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 12:19 am
by fragrantEmulsion
What exactly are you worried about? You purchased proprietary content and they inserted your personal info into the video somewhere?

That's actually really interesting, I can see how that could work but I don't see how it would survive being compressed/edited etc. I'm only a shitty programmer, not a cryptographer. It does seem like overkill to embed your personal info into every frame of the video, especially if the video is high quality. But, assuming the clips are costly and niche enough, it might end up being worth it for the studio.

When you purchase a video, are you able to download it immediately or is there a lag time when it becomes available? If there is a lag time, it could be sent to some server to encode with your data. My guess is that if there is identifiable information, it would be in a specific frame that happens in every video i.e. a logo frame etc. It could also be hidden in the audio, like how Mick Gordon hid 666 in a waveform in the DOOM soundtrack.

My guess is as long as you have re-edited the footage and converted the clips using handbrake or something, that frame would be distorted or outright destroyed.

I think that the main purpose of these "fingerprints" (assuming they exist) is to prevent people from re-selling the clips. You should be completely fine with distributing a free CH video to a handful of people on the internet.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 12:32 am
by zingg2
Sometimes people will claim to watermark something and then not actually do it, relying on the threat alone. But there are some pretty fancy watermarking tricks out there, including ones that can survive the editing process.

The safest approach for remaining anonymous is probably to make sure that however you acquire content, the provider doesn't have any information that traces back to you. This may be difficult to accomplish with paid content, though.

The next best approach is for multiple people to acquire the content, so that you can compare the results and get more information about what kind of watermarking may be in use. That still requires a good deal of technical skill to figure out, though, and there are watermarking schemes that would be difficult or impossible to reliably remove even given the knowledge of how they're done.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 12:34 am
by fragrantEmulsion
zingg2 wrote: Mon Mar 22, 2021 12:32 am But there are some pretty fancy watermarking tricks out there, including ones that can survive the editing process.
Can you give me some examples? I'm doing some research on it now.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 7:34 am
by torachan
fragrantEmulsion wrote: Mon Mar 22, 2021 12:19 am What exactly are you worried about? You purchased proprietary content and they inserted your personal info into the video somewhere?
tldr; I'm worried that I lose my anonymity and get a surprise bill.

About the content itself:
- I purchased a subscription to a premium site and downloaded various different videos. So if they embed something, it would be embed the user ID, which in turn can be eventually traced back to me if they payment providers share my information on request.
- There is a short delay before downloading (maybe like 1-4 seconds)
- I heavily cut bits and pieces from dozens of videos
- I re-render and re-encode the video using a proper video editing software

But I did some research myself and there are software providers that can create watermarks to videos that are almost impossible to get rid of. The question really is, do they do that here. It would be hard to imagine that the software is capable of somehow embedding this info to all the frames in that short amount of time. So most likely it is in some metadata (which is easily to get rid of).

Still I'm a paranoid person, so these things worry me.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 10:07 am
by torachan
fragrantEmulsion wrote: Mon Mar 22, 2021 12:34 am
zingg2 wrote: Mon Mar 22, 2021 12:32 am But there are some pretty fancy watermarking tricks out there, including ones that can survive the editing process.
Can you give me some examples? I'm doing some research on it now.
Here are two examples:
1. Pallycon
2. Custos

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 3:15 pm
by eatsl
well, i dont think some piece of code smuggled into a random part of a videofile would be likely to survive encoding or even the upload on a streaming side, but im no forensic data expert.
even if they would make that sequence somehow visible to be readable by a crawler (which would be rly inefficient) i doubt that any pornstudio would try that hard.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 5:21 pm
by doremi
The fact that you purchased the content and you are asking yourself this question should be a warning not to ignore, don't use it. If you can find a good copy of the same clip, use the copy that you found instead. :-)

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 6:11 pm
by torachan
doremi wrote: Mon Mar 22, 2021 5:21 pm The fact that you purchased the content and you are asking yourself this question should be a warning not to ignore, don't use it. If you can find a good copy of the same clip, use the copy that you found instead. :-)
I wish it was that easy though :-/ I'm using clips from over 30+ different videos in the series. So finding an alternative source for each of them is not only hard, but also extremely demotivating. Also since this is a niche area, some videos I couldn't even find.

Re: Video watermarking/tracking on CH videos

Posted: Mon Mar 22, 2021 10:39 pm
by torachan
Ok found an alternative source for the videos. It's a shame that I have to downgrade the quality from 4k to 1080p now. But at least I can sleep my nights in peace :-D

I'll be posting the sample for the CH this week :-)

Re: Video watermarking/tracking on CH videos

Posted: Tue Mar 23, 2021 1:01 am
by fragrantEmulsion
torachan wrote: Mon Mar 22, 2021 10:07 am Here are two examples:
1. Pallycon
2. Custos
This is interesting marketing material.

From the PallyCon article:
Spoiler: show
"The watermark detector then analyzes every frame of the pirated video content for identifying the original watermark. It uses the same secret key that the embedder used at the time of inserting the watermark. If the detection process finds the watermark payload, the session database can then be used for finding the session information that matches the payload key value."
From the Custos article:
Spoiler: show
"Even if an attacker knows that a media object is watermarked, it should be infeasible to remove the watermark without unacceptably damaging the host media in the process."

"A forensic watermark should not be audible or visible. To a human, a forensically watermarked media object should be indistinguishable from the unwatermarked original."

" For a watermark to be read reliably, “video registration” needs to be performed first, which is the reversal of clipping, rotation, timescale adjustment, and other reversible transforms. Independent software tools are available to do this, and Custos’ use of “bounty hunters” who voluntarily scan for watermarked content, puts “humans in the loop” who can intelligently reverse attacks to successfully read the watermark to claim a reward."
So this is a real technology that definitely exists. They are aware of common piracy tactics. It seems like your personal information will not be able to be exposed by just anyone (assuming that their private key store isn't ever leaked).

My immediate reaction is that you could defeat this via AI upscaling. Downscale the 4k content to 2k, then use AI upscaling to increase the resolution to 4k. Neither article even mentions neural networks or AI at all. AI upscaling basically dithers the content and then guesses what the missing pixels will look like. (This is an extreme oversimplification).

I might be wrong, but it would be fun to test. We'd need a bounty hunter key to do so.

It would also be fun to collect known samples of these videos and then see if we could train a neural network to detect the watermark. (It must have a pattern that would be perceivable to a machine).

As far as the practicality of this approach goes, it's probably not practical. I have used AI upscaling to make posters of low quality scans of old drawings. I know that there are people who use it to upscale older videos as well.

If you are able to find 1080p content that doesn't have your watermark, use that. 1080p at a good bitrate is perfectly acceptable.

Re: Video watermarking/tracking on CH videos

Posted: Tue Mar 23, 2021 5:28 am
by rawrrawr300
If you can acquire two copies of the same file from the same source with different credentials (accounts, ip addresses, etc.), it should be easy to determine if they are being altered. Just generate and compare checksums for the two files (e.g. see https://stackoverflow.com/questions/105 ... powershell). If they match, they should be safe to use.

Re: Video watermarking/tracking on CH videos

Posted: Tue Mar 23, 2021 7:51 am
by torachan
fragrantEmulsion wrote: Tue Mar 23, 2021 1:01 am As far as the practicality of this approach goes, it's probably not practical. I have used AI upscaling to make posters of low quality scans of old drawings. I know that there are people who use it to upscale older videos as well.

If you are able to find 1080p content that doesn't have your watermark, use that. 1080p at a good bitrate is perfectly acceptable.
I did some tests with some AI upscaling. The difference is quite small (at least on my eyes), need to test it with my 4k tv still. But at least on 1440p monitor the difference is too small to be worth it.

The bitrate in the videos is about ~3000kbps (on a 1080p video), this is about 40% of the source video bitrates. I tried comparing the quality with some other CHs and at least for me the difference is not too big. Need to try some upscaling techniques in the post-production.

Re: Video watermarking/tracking on CH videos

Posted: Tue Mar 23, 2021 7:55 am
by torachan
rawrrawr300 wrote: Tue Mar 23, 2021 5:28 am If you can acquire two copies of the same file from the same source with different credentials (accounts, ip addresses, etc.), it should be easy to determine if they are being altered. Just generate and compare checksums for the two files (e.g. see https://stackoverflow.com/questions/105 ... powershell). If they match, they should be safe to use.
I doubt this will work since the videos are using completely different bitrates/fps. Also the metadata is different. :/

Re: Video watermarking/tracking on CH videos

Posted: Tue Mar 23, 2021 4:30 pm
by pl3b
torachan wrote: Tue Mar 23, 2021 7:55 am
rawrrawr300 wrote: Tue Mar 23, 2021 5:28 am If you can acquire two copies of the same file from the same source with different credentials (accounts, ip addresses, etc.), it should be easy to determine if they are being altered. Just generate and compare checksums for the two files (e.g. see https://stackoverflow.com/questions/105 ... powershell). If they match, they should be safe to use.
I doubt this will work since the videos are using completely different bitrates/fps. Also the metadata is different. :/
I kind of don't get why it'd be impossible for you to find a torrent or so of a given scene at given resolution and then downloading that same scene at same resolution from the website. That or do it the other way around.