HKU Bulletin August 2010 (Vol. 11 No. 3)

24 The University of Hong Kong Bulletin 25 August 2010 Crime conscious scholars have developed a state-of-the-art facial recognition system that could help law enforcement officers correctly identify suspects partially caught on surveillance video. The technology, developed by a five-man team in the Centre for Information Security and Cryptography, can detect and extract the features of a partial face caught on video and reconstruct a three dimensional model of the face, eliminating hours of manual labour and potential human error. Associate Director of the Centre, Dr Chow Kam-pui who led the team with funding of $1 million from the Innovation and Technology Fund, said, “In normal cases of facial recognition we usually have a frontal view of the face, like when you go through Immigration, but in this case the face has to be in the right position for the computer to recognize it. If not, it will tell you it does not correspond to the full frontal image on the database and therefore is not the same person. This is problematic. “Again, many surveillance videos of people often do not capture full frontal images and, in terms of law enforcement, this means trawling through hours of footage manually, which is time consuming and the quality may not be good so the recognition rate is low. What we are suggesting is automating the system so that if law enforcement officers have to go through surveillance video searching for a suspect they do not have to do it manually. It can be automated and thus save time and eliminate human error. “The idea we are using is quite interesting. The basis is a generic three-dimensional image of the head which can be manipulated to produce a full-frontal 3D image from the available photograph, giving us a very good match. This is new to the commercial market. We can reconstruct the hidden part of the face to create a full face, and this gives a 90 per cent match. At the current stage, the system is used on digital CCTV cameras, rather than the analogue ones which are still the norm. However, the team’s demonstration prototype has attracted much attention, including a visit from a team of Hong Kong Immigration officers. Dr Chow and his colleagues are now in talks with manufacturers to integrate the software into existing face-recognition systems. NEW TECHNOLOGY to help fight crime A unique innovation from the Department of Computer Science is turning heads. In most people’s minds rap music is associated with voices from the margins of society and with black ghetto angst in particular. So the notion of Chinese hip hoppers may seem rather absurd. Yet, the rap music scene in China is thriving. Since its emergence in Beijing in the 1980s it has spread to all major cities including Shanghai, Kunming, Tsingdao, Shenzhen, and even far-flung Urumchi. Of course, as with Communism, the Mainland’s take on rap is uniquely Chinese. “It’s fashionable because it’s a western art music form,” says Dr Lee Watkins, who studied rap in South Africa, before taking up his position as a Post-doctoral Fellow in the Department of Music, last year. “Hip hop is a fashion, it’s ‘cool’ to be a hip hopper and learn a few dance tricks. African American rap is quite in your face, it has a lot of anger, but the Chinese hip hoppers are saying they are not experiencing gangsterism, or drive-by’s, so there’s no need for them to sing about that.” Indeed, it seems rap is hot in China simply by dint of being a western art form. “If it’s western it’s considered fashionable” explains Professor Watkins. “Even western classical music is; there’s a strong drive to play western instruments, partly because they appear to be new but also because they allow a certain freedom that is not experienced so much in Chinese education, for example. Chinese culture has so many restraints to work through. “Rock music in China in the early 1980s was also embracing this newfound freedom in China after the Cultural Revolution, and allowing young people to express views that may not have been consonant with the interests of the rulers.” Today, the another youth-dominated music genre – punk – is still fashionable amongst Chinese high school students. “It’s usually a teenage phase and a way of expressing their frustrations with entrance examinations.” Government censorship relieves Chinese rap of the sting of its western counterpart, so no railing against the state here. “There’s a lot of censorship,” says Dr Watkins. “So language is used to suggest things, because if they say things in an outright manner it could elicit censorship.” “Censorship means they won’t make as much of an impact on the music scene or develop a fan base. Early on rappers had to use record producers approved by the state and of course they would not produce music with confrontational messages.” Having grown up in Cape Town, where South Africa’s first rap music scene flourished, Dr Watkins developed a natural interest in hip hop. “As an area of research it appeals to me because these are voices from the margins. It challenges one to think critically but also, musically, I find it fascinating the level of musical knowledge and creativity that these people have.” “Rap music actually brings together many different musical forms into a four minute piece of music. I find it fascinating how music from all these different locations work their way into one song. And I realized also that Chinese rap music is under-researched.” He’s now combining anthropology with the musicological aspects of rap music. “A lot of aspects of hip hop are underground,” he says, “and the opening up of the Internet has provided another avenue for expressing opinions. “As far as the government in China is concerned as long as it stays underground, if it doesn’t take to the street to mobilize the masses, then it’s okay. At the moment it happens in nightclubs, it’s seen as entertainment. In China, many of the symbolic associations of hip hop and rap music do not apply; they are only interested in one aspect of it, and turning it into a commodity. “If they sing about political or social issues at all they tend to concentrate on the growing divide between rich and poor, the difficulty in finding employment for young people. They don’t address state policies as such, there’s no direct confrontation with the state, it’s rather about issues affecting youth and so on. “It’s not like African American rap and French rap music where it’s very direct. In South Africa and the United States people have realized the potential of rap as a money-making activity, with clothing lines and production companies. But the Chinese may not be looking towards making fortunes from it.” TAKING the rap Hip hoppers are taking China by storm. Research