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Image Scrubber: tool for anonymizing photographs taken at protests

everestpipkin.github.io

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Re: Image Scrubber: tool for anonymizing photographs taken at protests

#241

Post by 6nf »

pstuart wrote: post #114
hangphyr wrote: post #106

The timing of the release of this tool seems a bit innapropriate, given the state of rioting in a few US cities now. It's going to be incredibly draining on law enforcement in the US for a few years to identify and prosecute criminals involved in riots. Most victims already who have lost their homes, their businesses, and even their loved ones will mostly likely never see the criminals brought to justice given the sc…

What about identifying the police who are breaking the law? Not just the ones attacking peaceful protesters, but the agents provocateur? Peaceful protest is being squashed and de-legitimized. This is the flowering of fascism.

Looting and rioting and attacking shop owners trying to save their businesses and burning down cars and buildings. Not peaceful protests.

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#242

Post by kzrdude »

MauranKilom wrote: post #110
siberianbear wrote: post #56

Earlier quoted context omitted.

That wasn't really a "blur", though. A swirl like that is just moving pixels around. If know how the algorithm works, you can reverse it. Probably, it was done with a common program like Adobe Photoshop or Gimp or something. One could write a program that would just "unswirl" with various parameters and generate a bunch of images, and a human could pick out the one that looks like an unswirled image. If you can pick…

> That can't be done with a blur. In a blur, pixels are merged or averaged together and information is lost. I'd be careful with that assumption. The only thing that really loses information is the discretization back into 0-255 range, and that naturally loses very little information. If you consider the pixels as a large vector of values, you're effectively multiplying it by a matrix (plus discretization afterwards)…

So it would seem we should use a 0.5x + 0.5y blur to be sure to lose information - something that makes the matrix close to singular.

Also, how to handle the boundaries? We select a box in the image and blur that; we'd want to handle the boundaries in a way that also makes sure we lose information.

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#243

Post by jorblumesea »

anigbrowl wrote: post #97
Fezzik wrote: post #50

Earlier quoted context omitted.

For those who do not click through to the article: “Police say that there is no evidence the deaths have anything to do with the protests”. From my time in Portland, working at the courthouse as a court clerk during the Occupy movement, when hundreds of transient “protesters” camped out in the park, it is not surprising that some of those folks would OD or end up dead for reasons entirely not related to protesting bu…

What an amazing coincidence.

Given a large population of any individuals with only loose connections, is it not statistically likely that some will die? Especially given that those prone to protesting in the streets might have encountered trauma, or might have been from high risk populations in the first place.

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#244

Post by wizzwizz4 »

MauranKilom wrote: post #110
siberianbear wrote: post #56

Earlier quoted context omitted.

That wasn't really a "blur", though. A swirl like that is just moving pixels around. If know how the algorithm works, you can reverse it. Probably, it was done with a common program like Adobe Photoshop or Gimp or something. One could write a program that would just "unswirl" with various parameters and generate a bunch of images, and a human could pick out the one that looks like an unswirled image. If you can pick…

> That can't be done with a blur. In a blur, pixels are merged or averaged together and information is lost. I'd be careful with that assumption. The only thing that really loses information is the discretization back into 0-255 range, and that naturally loses very little information. If you consider the pixels as a large vector of values, you're effectively multiplying it by a matrix (plus discretization afterwards)…

You actually do lose information around the edges (it's cropped). But not much; the images are pretty compressible, so you can just predict those pixels.

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#245

Post by [deleted] »

yters wrote: post #155
throwaway2048 wrote: post #150

Earlier quoted context omitted.

This definitely seems like a good faith attempt to litigate the history of black oppression in the USA from first principles.

I am not aware of facts supporting the claim that african americans live under an authoritarian regime. I am aware that a number of african americans have been unjustly killed by police. That is a different claim than african americans are systematically oppressed by the US government. For instance, compare what is happening in the US to a real authoritarian regime such as the USSR. The government made millions of in…

[deleted]

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#246

Post by mceachen »

pgalvin wrote: post #121
mceachen wrote: post #62

Earlier quoted context omitted.

Google Photos isn't going to provide you with any authenticity claims, and metadata gets scrambled by both their "high quality" and "original" settings. If you want to make sure the actual, original image gets stored safely on another device automatically, use SyncThing or Resilio Sync.

> metadata gets scrambled by both their "high quality" and "original" settings. This is NOT true, at least for the "original" setting. Upload an image, download it again - the checksums are identical. If you modify the time/date or add comments within Google Photos, that new information is kept in a .json file instead of the exif data, but Google NEVER modifies the original photo if you select "original" quality.

That's not my experience with a couple Google Pixels, using original quality.

If you fetch your image via takeout or via the API, the image bytes are the same, but the EXIF headers have been changed.

I've tried in both a standard Gmail account and a custom domain. Same behavior.

Are you saying your file SHA is the same from your device and your takeout?

I wonder if I am seeing US-account-exclusive behavior?

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#247

Post by yters »

throwanem wrote: post #240
yters wrote: post #238

Earlier quoted context omitted.

There's the homicide rate, which jumped from 33.8% in 2014 to 55.4% in 2015, and has stayed above 50% since. https://en.wikipedia.org/wiki/Crime_in_Baltimore#Crime_stati... A little further down: "Homicides in Baltimore are heavily concentrated within a small number of high-poverty neighborhoods." So, my prima facie impression from these data points is the stand down has not benefitted the poor.

Would that be the homicide rate that's shown no significant first-derivative variance from the national rate since 2015? - the homicide rate that you're not even bothering to cite correctly? Those are figures per hundred thousand , not per hundred as you give them here. In either case, you're massively misrepresenting the "stand down" order, which was not a policy of indefinite disengagement, but rather a specific in…

This article from USA Today in 2018 implies the effect has been indefinite. Interesting graph, too, that shows the drop in police actively stopping petty crime correlates with a growth in homicides. I heard a Baltimore radio show in 2019 that said pretty much the same thing, highlighted by the police commissioner getting mugged in broad daylight as he was walking down the street with his wife.

https://www.usatoday.com/story/news/nation/2018/07/12/baltim...

“These guys aren’t stupid. They realize that if they do something wrong, they’re going to get their head bit off. There’s no feeling that anybody’s behind them anymore, and they’re not going to do it,” he says. “Nobody wants to put their head in the pizza oven when the pizza oven is on.”

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#248

Post by GreedCtrl »

noja wrote: post #64
wongarsu wrote: post #55

Earlier quoted context omitted.

Blurring isn't that good at destroying information, I think we mostly use it because it's the best looking censoring attempt. I would pixelate the faces to be just 4x4 giant pixels. It destroys nearly as much information as blacking them out while still not disrupting the image too much

I would guess that pixelisation for videos rather than pictures probably reveals more information the longer the video.

Yes, you would need to fix the pixels to an initial or average value. I remember Nintendo didn't do this a couple years ago, accidentally leaking the name of a new game mode [1] for Smash Ultimate.

[1] https://twitter.com/Lattie9001/status/1027204063811850240

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#249

Post by aith »

comboy wrote: post #239

Really weird that nobody in the thread is pointing out that this is basically a website that says "give me your photos, specifically from protests, which have details that you want to keep private". It doesn't matter that it theoretically all happen in the browser. You can serve different versions to different IPs etc. Every heuristic in me would be screaming don't use that if I would have a need for such tool.

It's a simple static site with no server involved. Everything happens client side. You could turn off your internet while you're using it if you wanted to make sure no data is exposed.

Re: Image Scrubber: tool for anonymizing photographs taken at protests

#250

Post by movedx »

comboy wrote: post #239

Really weird that nobody in the thread is pointing out that this is basically a website that says "give me your photos, specifically from protests, which have details that you want to keep private". It doesn't matter that it theoretically all happen in the browser. You can serve different versions to different IPs etc. Every heuristic in me would be screaming don't use that if I would have a need for such tool.

If it's all served in the browser, then simply download the page and use it offline.
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