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• Trolls in trouble

  6 juin 2013, par Mans — Law and liberty

  Life as a patent troll is hopefully set to get more difficult. In a memo describing patent trolls as a “drain on the American economy,” the White House this week outlined a number of steps it is taking to stem this evil tide. Chiming in, the Chief Judge of the Court of Appeals for the Federal Circuit (where patent cases are heard) in a New York Times op-ed laments the toll patent trolling is taking on the industry, and urges judges to use powers already at their disposal to make the practice less attractive. However, while certainly a step in the right direction, these measures all fail to address the more fundamental properties of the patent system allowing trolls to exist in the first place.

  System and method for patent trolling

  Most patent trolling operations comprise the same basic elements :

  1. One or more patents with broad claims.
  2. The patents of (1) acquired by an otherwise non-practising entity (troll).
  3. The entity of (2) filing numerous lawsuits alleging infringement of the patents of (1).
  4. The lawsuits of (3) targeting end users or retailers.
  5. The lawsuits of (3) listing as plaintiffs difficult to trace shell companies.

  The recent legislative actions all take aim at the latter entries in this list. In so doing, they will no doubt cripple the trolls, but the trolls will remain alive, ready to resume their wicked ways once a new loophole is found in the system.

  To kill a patent troll

  As Judge Rader and his co-authors point out in the New York Times, “the problem stems largely from the fact that, [...] trolls have an important strategic advantage over their adversaries : they don’t make anything.” This is the heart of the troll, and this is where the blow should be struck. Our weapon shall be the mightiest judicial sword of all, the Constitution.

  The United States Constitution contains (in Article I, Section 8) the foundation for the patent system (emphasis mine) :

  The Congress shall have Power [...] To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries.

  Patent trolls are typically not inventors. They are merely hoarders of other people’s discarded inventions, and that allowing others to reap the benefits of an inventor’s work would somehow promote progress should be a tough argument. Indeed, it is the dissociation between investment and reward which has allowed the patent trolls to rise and prosper.

  In light of the above, the solution to the troll menace is actually strikingly simple : make patents non-transferable.

  Having the inventor retain the rights to his or her inventions (works for hire still being recognised), would render the establishment of non-practising entities, which most trolls are, virtually impossible. The original purpose of patents, to protect the investment of inventors, would remain unaffected, if not strengthened, by such a change.

  Links

  • Taking on Patent Trolls to Protect American Innovation
  • Fact Sheet : White House Task Force on High-Tech Patent Issues
  • Make Patent Trolls Pay in Court
  • Constitution of the United States

• Greed is Good ; Greed Works

  25 novembre 2010, par Multimedia Mike — VP8

  Greed, for lack of a better word, is good ; Greed works. Well, most of the time. Maybe.

  Picking Prediction Modes
  VP8 uses one of 4 prediction modes to predict a 16x16 luma block or 8x8 chroma block before processing it (for luma, a block can also be broken into 16 4x4 blocks for individual prediction using even more modes).

  So, how to pick the best predictor mode ? I had no idea when I started writing my VP8 encoder. I did not read any literature on the matter ; I just sat down and thought of a brute-force approach. According to the comments in my code :

  // naive, greedy algorithm :
  //   residual = source - predictor
  //   mean = mean(residual)
  //   residual -= mean
  //   find the max diff between the mean and the residual
  // the thinking is that, post-prediction, the best block will
  // be comprised of similar samples
  

  After removing the predictor from the macroblock, individual 4x4 subblocks are put through a forward DCT and quantized. Optimal compression in this scenario results when all samples are the same since only the DC coefficient will be non-zero. Failing that, when the input samples are at least similar to each other, few of the AC coefficients will be non-zero, which helps compression. When the samples are all over the scale, there aren’t a whole lot of non-zero coefficients unless you crank up the quantizer, which results in poor quality in the reconstructed subblocks.

  Thus, my goal was to pick a prediction mode that, when applied to the input block, resulted in a residual in which each element would feature the least deviation from the mean of the residual (relative to other prediction choices).

  Greedy Approach
  I realized that this algorithm falls into the broad general category of "greedy" algorithms— one that makes locally optimal decisions at each stage. There are most likely smarter algorithms. But this one was good enough for making an encoder that just barely works.

  Compression Results
  I checked the total file compression size on my usual 640x360 Big Buck Bunny logo image while forcing prediction modes vs. using my greedy prediction picking algorithm. In this very simple test, DC-only actually resulted in slightly better compression than the greedy algorithm (which says nothing about overall quality).

  prediction mode	quantizer index = 0 (minimum)	quantizer index = 10
  greedy	286260	98028
  DC	280593	95378
  vertical	297206	105316
  horizontal	295357	104185
  TrueMotion	311660	113480

  As another data point, in both quantizer cases, my greedy algorithm selected a healthy mix of prediction modes :

  • quantizer index 0 : DC = 521, VERT = 151, HORIZ = 183, TM = 65
  • quantizer index 10 : DC = 486, VERT = 167, HORIZ = 190, TM = 77

  Size vs. Quality
  Again, note that this ad-hoc test only measures one property (a highly objective one)— compression size. It did not account for quality which is a far more controversial topic that I have yet to wade into.

• Neutral net or neutered

  4 juin 2013, par Mans — Law and liberty

  In recent weeks, a number of high-profile events, in the UK and elsewhere, have been quickly seized upon to promote a variety of schemes for monitoring or filtering Internet access. These proposals, despite their good intentions of protecting children or fighting terrorism, pose a serious threat to fundamental liberties. Although at a glance the ideas may seem like a reasonable price to pay for the prevention of some truly hideous crimes, there is more than first meets the eye. Internet regulation in any form whatsoever is the thin end of a wedge at whose other end we find severely restricted freedom of expression of the kind usually associated with oppressive dictatorships. Where the Internet was once a novelty, it now forms an integrated part of modern society ; regulating the Internet means regulating our lives.

  Terrorism

  Following the brutal murder of British soldier Lee Rigby in Woolwich, attempts were made in the UK to revive the controversial Communications Data Bill, also dubbed the snooper’s charter. The bill would give police and security services unfettered access to details (excluding content) of all digital communication in the UK without needing so much as a warrant.

  The powers afforded by the snooper’s charter would, the argument goes, enable police to prevent crimes such as the one witnessed in Woolwich. True or not, the proposal would, if implemented, also bring about infrastructure for snooping on anyone at any time for any purpose. Once available, the temptation may become strong to extend, little by little, the legal use of these abilities to cover ever more everyday activities, all in the name of crime prevention, of course.

  In the emotional aftermath of a gruesome act, anything with the promise of preventing it happening again may seem like a good idea. At times like these it is important, more than ever, to remain rational and carefully consider all the potential consequences of legislation, not only the intended ones.

  Hate speech

  Hand in hand with terrorism goes hate speech, preachings designed to inspire violence against people of some singled-out nation, race, or other group. Naturally, hate speech is often to be found on the Internet, where it can reach large audiences while the author remains relatively protected. Naturally, we would prefer for it not to exist.

  To fulfil the utopian desire of a clean Internet, some advocate mandatory filtering by Internet service providers and search engines to remove this unwanted content. Exactly how such censoring might be implemented is however rarely dwelt upon, much less the consequences inadvertent blocking of innocent material might have.

  Pornography

  Another common target of calls for filtering is pornography. While few object to the blocking of child pornography, at least in principle, the debate runs hotter when it comes to the legal variety. Pornography, it is claimed, promotes violence towards women and is immoral or generally offensive. As such it ought to be blocked in the name of the greater good.

  The conviction last week of paedophile Mark Bridger for the abduction and murder of five-year-old April Jones renewed the debate about filtering of pornography in the UK ; his laptop was found to contain child pornography. John Carr of the UK government’s Council on Child Internet Safety went so far as suggesting a default blocking of all pornography, access being granted to an Internet user only once he or she had registered with some unspecified entity. Registering people wishing only to access perfectly legal material is not something we do in a democracy.

  The reality is that Google and other major search engines already remove illegal images from search results and report them to the appropriate authorities. In the UK, the Internet Watch Foundation, a non-government organisation, maintains a blacklist of what it deems ‘potentially criminal’ content, and many Internet service providers block access based on this list.

  While well-intentioned, the IWF and its blacklist should raise some concerns. Firstly, a vigilante organisation operating in secret and with no government oversight acting as the nation’s morality police has serious implications for freedom of speech. Secondly, the blocks imposed are sometimes more far-reaching than intended. In one incident, an attempt to block the cover image of the Scorpions album Virgin Killer hosted by Wikipedia (in itself a dubious decision) rendered the entire related article inaccessible as well as interfered with editing.

  Net neutrality

  Content filtering, or more precisely the lack thereof, is central to the concept of net neutrality. Usually discussed in the context of Internet service providers, this is the principle that the user should have equal, unfiltered access to all content. As a consequence, ISPs should not be held responsible for the content they deliver. Compare this to how the postal system works.

  The current debate shows that the principle of net neutrality is important not only at the ISP level, but should also include providers of essential services on the Internet. This means search engines should not be responsible for or be required to filter results, email hosts should not be required to scan users’ messages, and so on. No mandatory censoring can be effective without infringing the essential liberties of freedom of speech and press.

  Social networks operate in a less well-defined space. They are clearly not part of the essential Internet infrastructure, and they require that users sign up and agree to their terms and conditions. Because of this, they can include restrictions that would be unacceptable for the Internet as a whole. At the same time, social networks are growing in importance as means of communication between people, and as such they have a moral obligation to act fairly and apply their rules in a transparent manner.

  Facebook was recently under fire, accused of not taking sufficient measures to curb ‘hate speech,’ particularly against women. Eventually they pledged to review their policies and methods, and reducing the proliferation of such content will surely make the web a better place. Nevertheless, one must ask how Facebook (or another social network) might react to similar pressure from, say, a religious group demanding removal of ‘blasphemous’ content. What about demands from a foreign government ? Only yesterday, the Turkish prime minister Erdogan branded Twitter ‘a plague’ in a TV interview.

  Rather than impose upon Internet companies the burden of law enforcement, we should provide them the latitude to set their own policies as well as the legal confidence to stand firm in the face of unreasonable demands. The usual market forces will promote those acting responsibly.

  Further reading

  • Tory-Labour pact could save data bill, says Lord Howard
  • Internet companies warn May over ‘snooper’s charter’
  • Snooper’s charter ‘should be replaced by strengthening of existing powers’
  • Exclusive : ‘Snooper’s charter’ would not have prevented Woolwich attack, says MI5
  • Search engines urged to block more online porn sites
  • Why technology must be the solution to child abuse material online
  • Google must take more action to police explicit content, says Vince Cable
  • Facebook bows to campaign groups over ‘hate speech’
  • Facebook sexism campaign attracts thousands online
  • Türkischer Ministerpräsident : Twitter ist eine Plage
  • Valls : « La traque sur Internet doit être une priorité pour nous »
  • La Cnil, futur juge d’Internet
  • “National security matter” : Third agency caught unilaterally blocking web sites