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Radios muffle firefighters' speech
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TM©20TH CENTURY FOX/REX
TECHNOLOGY
Movie pirates tracked to seat DIGITAL watermarks built into movies now make it possible to identify the seat a video pirate was sitting in when they made an illegal camcorder copy. Cheap copies of major movies such as Slumdog Millionaire (pictured) hit the streets as soon as the film is out. But now Noboru Babaguchi of Osaka University in Japan and colleagues claim that if you know which cinema a pirate operates from, you can locate where they were sitting by adding an audio watermark into the movie’s soundtrack. This is introduced during the mixing of the soundtrack by slightly varying the waveform of music and speech at regular intervals. Babaguchi created an audio watermark with a specific signal for each separate “channel” of a soundtrack, broadcast from different loudspeakers in the cinema. By analysing the recorded audio from
a camcorder copy, the team worked out how far away the camera’s microphone was from each of the loudspeakers, pinning it down to a specific seat. “This is a brand new application of the digital watermarking technique,” they write in a paper to be published in IEEE
“Audio watermarks tell you how far the pirate is from the cinema’s speakers, even identifying the seat” Transactions on Multimedia (DOI: 10.1109/tmm.2009.2012938. But the only way to identify the culprit would be to photograph ticket buyers, something which could create privacy problems in many countries, says Stephen Jenner of the Australian Federation Against Copyright Theft in Sydney, Australia.
–Slumdog watermark nails pirates –
Latest Taser is fired by shotgun
Digital radios hinder fire rescue
TASER stun guns are going wireless, doubling their range. The Taser XREP is an electrically charged dart that can be fired from up to 20 metres away with a 12-gauge shotgun. Upon impact, its barbed electrodes penetrate a victim’s skin, discharging a 20-second burst of electricity to “distract, disorient and entice the subject to grab the projectile”, says Taser. But grabbing the dart routes the shock through the hand, making it difficult to let go and spreading the pain further. While the XREP delivers a lower voltage for a longer time, a spokeswoman for Taser says its effect is similar to existing versions. Commercial production of the XREP is due to start later this month, with US police departments and the US military expected to be using the weapons by the end of 2009.
MANY firefighters in the US can no longer hear their colleagues amidst the noisy maelstrom of a fire rescue. The problem? Their brand new digital two-way radios. The US has been equipping its emergency crews with digital radios because they take up half the radio spectrum of the old analogue ones. But fire crews complain that they cannot hear what their colleagues are saying. It turns out the problem is in the “vocoders” that digitise speech and then compress the bits into a 12.5-kilohertz band of radio spectrum. Vocoders are designed
60
The percentage of US employees who steal proprietary company data when they are fired or leave their job voluntarily
for normal human speech, so their output degrades in the presence of loud background noise, or if a breathing mask muffles the firefighter’s voice. DJ Atkinson at the Institute for Telecommunication Sciences in Boulder, Colorado, who tested the radios, points out that most emergency workers can step away from noisy spots to talk, but firefighters cannot. Now radio manufacturers, fire safety groups and government agencies are attempting to fix the problem by designing radios that work with breathing masks, and developing new procedures that keep microphones closer to the mouth and away from other sources of noise.
“Rights holders are now in the driving seat” Amazon explains why it has given in to demands by the Authors Guild to allow publishers to disable the text-to-speech feature on its Kindle 2 ebook reader. The guild fears that computerised vocalisation will harm sales of audio books (The New York Times, 27 February)
7 March 2009 | NewScientist | 17
TM©20TH CENTURY FOX/REX
TECHNOLOGY
Movie pirates tracked to seat DIGITAL watermarks built into movies now make it possible to identify the seat a video pirate was sitting in when they made an illegal camcorder copy. Cheap copies of major movies such as Slumdog Millionaire (pictured) hit the streets as soon as the film is out. But now Noboru Babaguchi of Osaka University in Japan and colleagues claim that if you know which cinema a pirate operates from, you can locate where they were sitting by adding an audio watermark into the movie’s soundtrack. This is introduced during the mixing of the soundtrack by slightly varying the waveform of music and speech at regular intervals. Babaguchi created an audio watermark with a specific signal for each separate “channel” of a soundtrack, broadcast from different loudspeakers in the cinema. By analysing the recorded audio from
a camcorder copy, the team worked out how far away the camera’s microphone was from each of the loudspeakers, pinning it down to a specific seat. “This is a brand new application of the digital watermarking technique,” they write in a paper to be published in IEEE
“Audio watermarks tell you how far the pirate is from the cinema’s speakers, even identifying the seat” Transactions on Multimedia (DOI: 10.1109/tmm.2009.2012938. But the only way to identify the culprit would be to photograph ticket buyers, something which could create privacy problems in many countries, says Stephen Jenner of the Australian Federation Against Copyright Theft in Sydney, Australia.
–Slumdog watermark nails pirates –
Latest Taser is fired by shotgun
Digital radios hinder fire rescue
TASER stun guns are going wireless, doubling their range. The Taser XREP is an electrically charged dart that can be fired from up to 20 metres away with a 12-gauge shotgun. Upon impact, its barbed electrodes penetrate a victim’s skin, discharging a 20-second burst of electricity to “distract, disorient and entice the subject to grab the projectile”, says Taser. But grabbing the dart routes the shock through the hand, making it difficult to let go and spreading the pain further. While the XREP delivers a lower voltage for a longer time, a spokeswoman for Taser says its effect is similar to existing versions. Commercial production of the XREP is due to start later this month, with US police departments and the US military expected to be using the weapons by the end of 2009.
MANY firefighters in the US can no longer hear their colleagues amidst the noisy maelstrom of a fire rescue. The problem? Their brand new digital two-way radios. The US has been equipping its emergency crews with digital radios because they take up half the radio spectrum of the old analogue ones. But fire crews complain that they cannot hear what their colleagues are saying. It turns out the problem is in the “vocoders” that digitise speech and then compress the bits into a 12.5-kilohertz band of radio spectrum. Vocoders are designed
60
The percentage of US employees who steal proprietary company data when they are fired or leave their job voluntarily
for normal human speech, so their output degrades in the presence of loud background noise, or if a breathing mask muffles the firefighter’s voice. DJ Atkinson at the Institute for Telecommunication Sciences in Boulder, Colorado, who tested the radios, points out that most emergency workers can step away from noisy spots to talk, but firefighters cannot. Now radio manufacturers, fire safety groups and government agencies are attempting to fix the problem by designing radios that work with breathing masks, and developing new procedures that keep microphones closer to the mouth and away from other sources of noise.
“Rights holders are now in the driving seat” Amazon explains why it has given in to demands by the Authors Guild to allow publishers to disable the text-to-speech feature on its Kindle 2 ebook reader. The guild fears that computerised vocalisation will harm sales of audio books (The New York Times, 27 February)
7 March 2009 | NewScientist | 17