【单选题】

Britain, somewhat proudly, has been crowned the most watched society in the worlD、The country boasts 4.2 million security cameras (one for every 14 people) , a number expected to double in the next decade.

A、typical Londoner makes an estimated 300 closed-circuit televisionCCTV) appearances a day, according to theBritish nonprofit surveillance Studies Network, an average easily met in the short walk between Trafalgar Square and the Houses of Parliament. Public opinion on this state of affairs is generally positive, according to recent polls.And how useful isCCTV in busting bad guys Not much, according to Scotland YarD、In terms of cost benefit, the enormous expenditure has done very little in actually preventing and solving crime.
Right underBigBrother- s nose, a new class of guerrilla artists and hackers are comrnandeering the boring, grainy images of vacant parking lots and empty corridors for their own purposes. For about $ 80 at any electronics supply store and some technical know-how, it is possible to tap into London’sCCTV hotspots with a simple wireless receiver (sold with any home-security camera) and a battery to power it.Dubbed "video sniffing," the pastime evolved out of the days before broadband became widely available, when "war-chalkers" scouted the city for unsecured Wi-Fi networks and marked them with chalk using special symbols. Sniffing is catching on in other parts ofEurope, spread by a small but globally connected community of practitioners. "It’s actually a really relaxing thing to do on a Sunday," says Joao Wilbert, a master’s student in interactive media, who slowly paces the streets in London like a treasure hunter, carefully watching a tiny handheld monitor for something to flicker onto the screen.
The excursions pick up obscure, random shots from the upper corners of restaurants and hotel lobbies, or of a young couple shopping in a house wares department nearby.Eerily, baby cribs are the most common images. Wireless child monitors work on the same frequency as other surveillance systems, and are almost never encrypted or secureD、
Given that sniffing is illegal, some artists have found another way to obtain security footage: they ask for it, in a letter along with a check for ￡10. In making her film "Faceless,"Austrian- born artist Manu Luksch made use of a little-known law, included withinBritain- sData ProtectionAct, requiringCCTV operators to release a copy of their footage upon the request of anyone captured on their cameras. "Within the maximum period of 40 days I received some recordings in my mail," says Luksch. "And I thought, Wow, that works well. Why not make a feature length, science-fiction love story "After four years of performing, staging large dance ensembles in public atriums and submitting the proper paperwork, Luksch produced a haunting, beautifully choreographed film and social commentary, in which the operators have blocked out each and every performer’s face, in compliance withBritain- s privacy laws.
"TheDuelists," one of the more well knownCCTV movies, was shot by filmmakerDavid Valentine entirely with the security cameras in a mall in Manchester. He was able to cajole his way into the control booth for the project, but he is also credited with having advanced video sniffing to an art form and social tool. He’s collaborated with MediaShed, an organization based in Southend- on-Sea just outside London that works with homeless youth, using sniffing as a way to gain their interest and re-engage them with society.
In some cases video sniffing has morphed into a form of hacking, in which the sniffer does more than just watch. Using a transmitter strong enough to override the frequency that most cameras use, sniffers can hijack wireless networks and broadcast different images back to the security desk. Most sniffers, hijackers and artists usingCCTV are critical of the present level of surveillance, but they’ re als