Public-key Cryptography - An Idea For a More Sophisticated Dash Camera

[SawMaster]

I too resist government intrusions into my rights, but only so far as it doesn't make my situation worse. My plan is simple: if at all possible I will swap the card in my cam for the spare I carry before a chance of confiscation occurs. I will not state that I have a cam unless they ask. I will not state that the cam was recording unless they ask. And I certainly will not state that the card in the cam is the same one which recorded the incident, which is a question they are highly unlikely to ask anyhow, so if they want what they see then let them have it. With any luck my attorney will have the card with the un-tampered-with evidence on it before they discover they've been had, and I've committed no crime which they can show any proof of having happened so they can't charge me with anything (corpus delecti).

If you can't overpower your opponent, outsmart them instead.

Phil

 

[fiji]

If you faint after the incident:
- police will found the dashcam and extract the sd card without asking;
- car is seized by police and the judge or the lawyer counterparty will ask to access to data into dashcam

So you really need public key cryptography or strong cryptography to protect your data.

I think an Android device (used as dashcam) can protect you too if you enable full encryption in the device. Android encryption is not so strong as iOS one, but everything is better than nothing

 

[Rajagra]

if at all possible I will swap the card in my cam for the spare I carry before a chance of confiscation occurs.

Hmmm. Have we found the real reason for the Mini0806 having two memory slots? One to record on and take out quickly, and the other to leave in for confiscation. Luckily slot B is the one it prefers to record on and is easiest to get at (unless you mount upside down.)

 

[Sabe]

Boy i'm glad to live in a country where i don't have to be afraid our own police.

 

[fiji]

If you kill someone on the street with your car going at 250 km/h and you have a dashcam in your car, I wish police of your country try to get the sdcard to analyze it. Police should do this ...
On the other side, if I kill someone with my car going at 250 km/h, I hope I'm using some cryptography and save my ass. This is the game, everyone tries to win ...

 

[SawMaster]

I'm not terribly worried about it. My main concern is two-fold: One, they may not know how to safely retrieve the data and end up erasing it. Two is that happening intentionally. My Lawyers are trustworthy and are legally compelled to share evidence with the authorities if they ask for it. That is served by them giving the authorities a true copy so the original is safe and beyond their control and they can't alter or destroy it. The original only needs to appear in actual Court proceedings, not until them.

One local Cop has a grudge against me, and I've dealt with several others whose IQ is in the negative digits. One threatened to arrest me when I called for assistance because I am almost deaf- yes he said that was his reason, and he did nothing about the situation which ended up costing a 3rd party who was involved $1700. Two others have refused to even look at clearly visible physical evidence, preferring witness statements which were clearly collusive and contrived.

Since the other Cops won't keep their own idiots restrained I now no longer trust or have much use for any of them. My lawyers are where any evidence I have goes to. At least they are not this stupid so I may have a fair chance then.

As to public-key encryption, some of the most widely used systems have a "back-door" and the US government sees whatever it wants to with them. Similar supposedly more secure systems used by banks for international transfers have been hacked already (not brute force but intelligent hacks). Governments can afford to hire folks who can do that so don't count on any simple encryption to be effective. But they can't read what they don't have so the simplest solution is to be sure they don't get the data in the first place

I don't fear what my cam shows, but other folks should fear it because it does not lie and it will clearly show that they do.

Phil

 

[arcticfire]

I thought the police could usually work out what speed you were going in a crash anyway without video footage? I stopped putting GPS co-ords stamps (and the speed with the Mini) and only show the date and time. This way if I'm going a few miles above the speed limit in an incident I can just supply a re-encoded copy of the video file without embedded GPS coords and not be demonised by someone being pedantic because I was doing 34mph in a 30mph limit. But, if I needed to prove my speed then I'll still have the option to use the GPS embedded video file instead. I appreciate that your speed could be roughly calculated by using the time stamp and the distance between two objects in the footage but could you argue that the time stamp isn't calibrated for such purposes and therefore wouldn't be accurate enough to use for such? I'm not sure, just making the assumption though.

The good thing I've found with having a dash cam is obviously it provides me with a pretty much indisputable witness to an incident but it also makes me very aware of my own driving because it works both ways!

If you aren't doing anything wrong then I don't see why you would need the encryption, it kind of reminds me of guns that have a finish which resists fingerprints. Password protecting the camera is good (for those which do it) for commercial purposes to stop drivings from tampering with the settings and couple that with a lockable card slot then it's even better!

 

[DT MI]

... appreciate that your speed could be roughly calculated by using the time stamp and the distance between two objects in the footage...

You don't need a time stamp or GPS data. All that's needed is the frame rate of the video (30FPS for example) and the distance between 2 points in the video and it's a simple calculation using the number of frames it takes to get from point A to point B.

 

[arcticfire]

Never thought of that, I guess that would make it pretty accurate? What about acceleration and deceleration?

 

[DT MI]

...What about acceleration and deceleration?

Measure how far you travel between individual frames - it will show acceleration, deceleration or constant speed. More accurate than any other method, including the speedometer.

 

[arcticfire]

Time for a new dash cam feature then, randomly varying FPS! lol

 

[DT MI]

Time for a new dash cam feature then, randomly varying FPS! lol

People are already 'creative' in trying to hide their own wrong-doing, let's not build a method into the technology designed to protect the innocent.

 

[jokiin]

Time for a new dash cam feature then, randomly varying FPS! lol

Variable frame rate does exist already actually

 

[kamkar]

Well if its just to hide your own stupid well then i am sorry but then i cant really care for that, just like i have allways said that dashcam footage with a radar detector in it is pretty dual standarts to me.

Offcourse if Denmark was worse off than it allready is and the police got even more out of hand and even more incompetent in ther job, then my take on things might change.
But i do think if you put yourself above the law ( even if it is a pretty stupid law ) then you should face the consequence of that if you get busted.
I know its never fun beeing caught with the hand down the cookie jar, but when you stand there looking stupid it is even more stupid if you start to whine about it, and lying saying no thats not my hand in the jar, its a hand that suddenly grew out of my back and jumped in there on its own.

Be a man about it, and be done with it.
Like a wise American once said ( i think ) Dont do the crime if you cant do the time.

Regarding police performing bad, thats a frightning prospect and a issue that if a population in a country feel that if should go strait to the top of problems that need to be fixed in that country.
And if you dont do that well then you have taken the first step onto a slide that end back in the stoneage.

 

[fiji]

You should not incriminate yourself. In USA you can avoid actions damaging you. That is, if I have a video and it can use against me then I can avoid to show it. It's a logical concept, the same that allow you to not answer with or without your lawyer.

So, if I have a video and it can be used against me, it's my legitimate interest to hide the proof. The other car owner will do the same.

This is the same when police asks me to say the password of my encrypted hard disk or my iphone: I can say I don't remeber or I don't want to tell it. http://kernelmag.dailydot.com/issue...ctions/11071/police-force-password-cellphone/

If you like EFF, you should know they say you should have a strong password for everything.

 

[DT MI]

You should not incriminate yourself. In USA you can avoid actions damaging you. That is, if I have a video and it can use against me then I can avoid to show it. It's a logical concept, the same that allow you to not answer with or without your lawyer.

So, if I have a video and it can be used against me, it's my legitimate interest to hide the proof. ....

What you are referring to is the 'Fifth Amendment' to the U.S. Constitution.

What it says (in a simplistic sense) is that you cannot be compelled to testify against yourself. Physical evidence that you hold can be obtained and used against you. The act of hiding or destroying evidence can actually result in additional charges being brought against you.

https://www.law.cornell.edu/wex/fifth_amendment

 

[fiji]

Ok. If I have the video I have to give it to the police. But if video is password protected, do I have to give the password?

Turning over the password “is pretty clearly protected by the Fifth Amendment privilege against compelled incriminating testimony,” advices Fakhoury, but that’s not the end of it. “If the Fifth Amendment protects you, that doesn’t mean the government doesn’t get your cooperation”—meaning you might be expected to decrypt the device, but that anything found on it can’t be used against you in a court of law.

It also depends if the authorities already know what’s on the device. In one case where the defendant was accused of possessing child pornography, law enforcement had already seen some of the files prior to the device shutting down. The defendant was subsequently forced to surrender his password on the grounds that “providing access to the unencrypted Z drive adds little or nothing to the sum total of the Government’s information about the existence and location of the files that may contain incriminating information.”

If the devices under investigation are known to belong to you, the authorities are more likely to push for your password (even if it is still arguably unconstitutional), as compared to if they were in a shared property where plausible deniability might apply. The upshot of this is that law enforcement’s approach—and the legal recourse open to you—vary a great deal depending on the specifics of each individual case.

- See more at: http://kernelmag.dailydot.com/issue...orce-password-cellphone/#sthash.qdWcvi0l.dpuf

so:
1) device can belong to another person who share the car with you
2) who owns the password? You or your partner or the car owner?
3) what if I miss my password? I set it 5 years ago and I never checked my video files until now. I don't remember, please read in my brain using your Matrix program
4) password is 123456$$ ... ehi, what? doesn't work? maybe a bug in encrypt program / firmware or when I set the password I set the wrong one ... oh my God! Damn bugged firmware!
5) can't give the password, I used that dashcam to do a porn video with my wife yesterday
6) don't ask to me, ask to my lawyer
...

 

[Rajagra]

There is another method where an encrypted container file contains multiple sets of data each with its own encryption key. Some of these sets are user data, and the user should know the key. But other sets are dummy data with random keys and the user does not know the key. If authorities try to force you to divulge the keys, you can claim all but one data set is dummy data. You have plausible deniability - there is no way they can disprove your claim, as that is the way the system is designed to work.

Moreover, even if you are tortured, there is no reason to hand over any key, because they will continue to torture you to gain access to the dummy data which you don't have the keys to.

Downside is it must be very wasteful of space, so not much use on dash cams unless you are really paranoid.

 

[fiji]

I use truecrypt/veracrypt hidden volume on all my hard disks, it's not a wasteful of space: it's the space of your dummy data. So if you create an outer partition of 100% space, you put a dummy video (3% space) you can create a hidden volume of 97% space (where store all your real video). That is, you don't waste your space. It's quite strange you only used 3% of your sd card, but this is a free world, it's up to you ... Consider you should have a smart ui to hide this behaviour. That is, if police put the sd card in your dashcam and it autostart recording (in your hidden space, as default behaviour), when they umount the unit and access with fake password they don't see the video they just recorded, so ... Hidden volume is ok but you should have a smart way to tell your dashcam if record on hidden volume or outer volume and this is not a plug-&-play way to go ...

 

[EyeGaze]

Interesting discussion. I'm going to buy a dash cam form my car and the first problem I started thinking is " there is 50% of probability it will used against me"?
I mean: if a have a collision may be I will not able to get my dash cam (because i'm in a hospital, for example) There ere cases where a recording may be used against me, because I caused the collision... but also when a partial vision of the accident show me guilt even if I'm not (pedestrain incidents, for example, seems always to show the car as a killer, but is not always true)

Someone, in the previous page, linked to a discussion about a microSD adaptator capable to encript data on fly. Very interesting but I cant find if really there is such product and what' s the name... any idea?