日本某电器巨头公司新近研发了一种智能广告牌，能够通过面部识别技术分辨路人的性别和年龄，然后“投其所好”播放不同类型的广告内容，比如，看到女性就会播放香水广告等。

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A virtual mannequin appearing in the digital billboards.

In Steven Spielberg's sci-fi film Minority Report, an interactive³（交互式的） ad shouts to Tom Cruise's character "John Anderton, you could use a Guinness!" – having identified him by scanning his iris⁴（虹膜） . In Japan, sci-fi prophecy（预言） is now becoming reality, with the first digital billboards（广告牌） tailored（裁制） to passing shoppers tried out in malls.

Produced by the electronics giant NEC, the ad signage uses facial recognition software and can identify the shopper's gender⁵ (with 85-90% accuracy), ethnicity and approximate age. With obvious attractions for marketers, they can then be targeted with ads for appropriate products – perfumes for women, for example.

Still in the future for now are individual-specific ads as in Minority Report, but the potential is there for the software to measure the distance between features – a distinctive⁶ aspect of our face that does not change with disguises（伪装，假装） or even surgery – and then find a match on a database in less than a second. The ad panels have so far caused little concern in Japan, where there is less sensitivity to big business keeping tabs on citizens; but NEC now plans to introduce them abroad, and western consumers may be more resistant⁷.

"We don't expect the billboard¹ to look back at us, but that is exactly what is happening now," says Marc Rotenberg, the director of the Electronic Privacy Information Center (Epic), a Washington DC-based research centre that aims to protect privacy. "Companies are increasingly impatient to get to us, and once these practices are commonplace it will be hard to reverse them."

But NEC insists there is little to fear: "As our system does not store any images – it stores only the analysed results [viewers' age and sex] based on those images – we feel there is no privacy issue."

Along with Blade Runner-style 3D ads, Tokyo now also boasts a camera-equipped vending⁸ machine（自动售货机） that suggests drinks to consumers according to their age and gender. Weather conditions and the temperature are taken into account too.