Mobile radio – look as you listen?

Aug 01, 2007
Mobile radio – look as you listen?
A new audio service delivers images to go with the radio program – for instance CD covers or concert photos. © Fraunhofer HHI

Eyes can listen too: Researchers have developed a new audio service for cell phone radios in which the sound is accompanied with matching images – such as CD covers or concert photos. Sound and image take up only a quarter of the bandwidth of conventional radios.

The listener cheerfully hums along with the music playing on his cell phone radio. It wouldn’t be a bad idea to buy this song – but on which CD was it released?

A quick glance at the display reveals the answer: It shows additional information about each song in the form of images such as the CD cover, photos of one of the band’s concerts, or – if the music happens to be a soundtrack – screenshots from the film. What’s more, even including all pictures the service requires only a quarter of the bandwidth currently occupied by the conventional digital stereo signal via DAB. This cuts the cost of transmitting the image and the sound to only about 25 percent.

To achieve this result, the research scientists at the Fraunhofer Institute for Telecommunications, Heinrich-Hertz-Institut HHI in Berlin, who developed the “visual radio”, first had to compress the audio signal.

“Instead of the usual DAB format, we use the High-Efficiency Advanced Audio Coding (HE-AAC) radio format developed by our colleagues at Coding Technologies, a Fraunhofer spin-off,” says HHI head of department Dr. Ralf Schäfer. “This allowed us to reduce the bandwidth of the sound from 192 kilobits per second to 48 kilobits per second.” In order to economize on transmission capacity for the images, the experts compress those too. They do it with the same technology that is used for mobile television on the cell phone.

“Our goal in this case was to apply the compression technique efficiently to fixed images as well,” says Schäfer. “We succeeded: If we transmit a new image with the sound roughly every two seconds, it only adds about 10 to 15 kilobits per second to the load.” This is achieved by using the currently most efficient video coding method H.264/AVC, in the development and standardization of which the HHI researchers played a significant role.

Visual radio is set to go into trial operation in several regions of Germany this August – on various public radio stations. Anyone who is interested can also try out visual radio at the joint Fraunhofer stand at the IBC trade fair, to be held in Amsterdam from September 7 to 11 (Hall 8, Stand 381). Schäfer sees visual radio as a new service primarily for mobile TV networks. In the long term, the researcher hopes, the new visual format could take the place of traditional radio.

Source: Fraunhofer-Gesellschaft

Explore further: Faradair team determined to make hybrid BEHA fly

add to favorites email to friend print save as pdf

Related Stories

Audi to develop Tesla Model S all-electric rival

9 hours ago

The Tesla Model S has a rival. Audi is to develop all-electric family car. This is to be a family car that will offer an all-electric range of 280 miles (450 kilometers), according to Auto Express, which ...

New largest number factored on a quantum device is 56,153

10 hours ago

(Phys.org)—Researchers have set a new record for the quantum factorization of the largest number to date, 56,153, smashing the previous record of 143 that was set in 2012. They have shown that the exact same room-t ...

Recommended for you

Faradair team determined to make hybrid BEHA fly

17 hours ago

Aiming to transform their concept into a real success, the Faradair team behind a six-seat Bio-Electric-Hybrid-Aircraft (BEHA) have taken this hybrid aircraft project into a crowdfunding campaign on Kickstarter. ...

How polymer banknotes were invented

Nov 26, 2014

The Reserve Bank of Australia (RBA) and CSIRO's 20-year "bank project" resulted in the introduction of the polymer banknote – the first ever of its kind, and the most secure form of currency in the world. ...

Enabling the hearing impaired to locate human speakers

Nov 26, 2014

New wireless microphones systems developed at EPFL should allow the hearing impaired to aurally identify, even with closed eyes, the location of the person speaking. This new technology will be used in classrooms ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.