Day: 20 July 2016

Pixellating or Blurring Text in Photoshop Creates Identifiable Patterns ⇥ fusion.net

Kashmir Hill summarizes for Fusion a study by Steven Hill, et. al. (PDF):

“In many online communities, it is the norm to redact names and other sensitive text from posted screen shots,” write the researchers, specifically citing Reddit. “Mosaicing and blurring have also been used for the redaction of high-profile government documents and celebrity social media.”

They should probably stop doing that. The UC-San Diego researchers found that they could use statistical models—”so-called hidden Markov models”—to generate the blurring or pixelation of lots of numbers, letters, and words, to the point that their software program could match a known redaction to an unknown redaction to figure out what it says. The biggest challenge is figuring out the font and size of the underlying text which the researchers need for their deciphering. They say it works better than a brute-force technique for deciphering pixelated images discussed by Dheera Venkatraman in 2007.

There’s a great reason why intelligence agencies redact documents by placing an oversized black bar on top of the text in question, then printing and scanning the document to make it unrecoverable. The latter steps were not performed by the New York Times in 2014, and it lead to the unintentional exposure of sensitive information from a Snowden-leaked NSA document.

Limiting Harassment, Not Speech

Madeleine Sweet:

While [Milo] Yiannopoulos uses the term “free speech” to declare what Twitter, in his opinion, deprived him of — he clearly could not have meant it in the legal sense, though he likely meant to evoke the same sense that many horrible Americans have; this sense that they can spew whatever bigotry they want without repercussion because “the first amendment”. Perhaps he did mean it in the legal sense, in which case he is as dumb as all of his bigoted drones trolling the #FreeMilo hashtag (also: free him from what?) and attempting to make some correlation between the bill of rights and [Twitter] banning a bigot and a hate-monger from their forum.

Much like when Brendan Eich was removed as Mozilla’s CEO after his contributions to Prop 8 became known, and when Charles Johnson was banned from Twitter for raising funds to “take out” DeRay Mckesson, it was entirely within the realm of reason for Yiannopoulos to be banned as well. By goading his followers into targeted harassment repeatedly and expressing no contrition for it, he became an unwelcome and toxic presence.

Yiannopoulos’ defence is that Twitter is a “safe space for Muslim terrorists and Black Lives Matter extremists”. Racism and xenophobia aside, it should be noted that, last summer, Twitter began a crackdown on accounts that tweeted in support of ISIS. The result? A 40% decline in related activity.

In a weird way, Yiannopoulos is right: Twitter has a much bigger problem with abuse than any single user can represent. But he’s part of the problem. Twitter should not be a safe space for inciting hatred and targeted violence.

Update: Leigh Alexander, writing for the Guardian:

Banning one man won’t undo the small but poisonous cultural legacy he’s created, nor erase the playbook for defamation and harassment online that he’s played a key role in scripting. Twitter has far, far more work to do.

Without this further work, Yiannopoulos’s ban – and even the subsequent catty gloating from us folks on the left – all just stands to aggravate a wound that’s been attracting flies to social media discourse for too long already. An isolated ban just lets Yiannopoulos make himself a martyr for “free speech” – it enables him to argue that social media offers special treatment to those on the political left that it does not accord the right, and perpetuates the pernicious myth that the main interest of the progressive left is in shutting its ears to offensive things or in “censoring” those who ruffle feathers.