Cedar Audio has secured as second patent for its Unwrap – a process that makes previously unusable audio clear and intelligible.
Wrapping is an form of clipping distortion where, instead of being flattened at the maximum and minimum amplitudes of the audio format used, samples are wrapped around and appear with the right shape but at the wrong amplitude. This form of distortion only occurs on digital recorders, but has been encountered on devices ranging from small, handheld units such as interview recorders to large, professional recorders used in the music and movie industries. The audible consequence of wrapping is a loud and aggressive form of distortion that can appear to obliterate the wanted signal.
Unwrap eliminates wrapping errors and offers an Auto Level control that automatically normalises the unwrapped signal to 0dB. The results can be dramatic, even revealing speech and making it completely clean and intelligible where none was audible in the first place. Where other problems in the audio exist, these can then be addressed using additional Cedar processes such as broadband noise reduction, crackle and hum removal.
‘For many years, customers sent us similar sounding audio samples that couldn’t be repaired using any existing technology. The problem was sample wrapping, an unusual form of clipping distortion where, instead of being flattened at the maximum and minimum amplitudes of the audio format used, samples appear with the right shape but at the wrong amplitude,’ explains Cedar Audio MD, Gordon Reid. ‘Although relatively rare, this was being encountered on digital audio recordings made using devices ranging from small, handheld units such as interview recorders to the large, professional recorders used in the film and broadcast industries, and the consequence was a loud and aggressive form of distortion that could totally obliterate the wanted signal and render the audio useless.
‘Unable to resist the challenge, we developed a unique algorithm to identify and correct sample wrapping distortion, and today we’re proud to announce that our second patent for this technology – first unveiled in our Unwrap module for Cedar Cambridge – has been granted.’
More: www.cedaraudio.com
