Song-swapping portal Napster has licensed new 'acoustic fingerprinting' technology after its attempts to enforce an effective filtering system were branded 'disgraceful' by a US federal Judge.

The TRM (This Recognises Music) system, made by US company Relatable, identifies audio recordings based on the acoustic properties of their waveforms.

Napster was ordered to implement a file-filtering system to block visitors to its site from downloading music files after being taken to court by the Recording Industry of America Association over copyright infringements.

"Digital fingerprinting technologies are developing rapidly, and Relatable's new acoustic fingerprinting technology shows great promise," said Hank Barry, Napster's interim CEO.

"We are working closely with Relatable's engineers to coordinate their technology with our file-filtering systems. We hope they will be a substantial part of our overall filtering system," said Barry.

The TRM system will be applied to Napster's new subscription service, set to begin in July. TRM will also be introduced to the current Napster site as soon as it has been refined.

Napster's future is dependent on its ability to successfully implement a file-filtering system blocking the download of copyrighted materials. Let's hope this attempt is more successful than previous ones.