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Scalable Audio Coding Employing Sorted Sinusoidal Parameters, M. Raad, I. Burnett, Alfred Mertins
Scalable Audio Coding Employing Sorted Sinusoidal Parameters, M. Raad, I. Burnett, Alfred Mertins
Faculty of Informatics - Papers (Archive)
This paper describes the use of sorted sinusoidal parameters to produce a fixed rate, scalable, wideband audio coder. The sorting technique relies on the perceptual significance of the sinusoidal parameters. Sinusoidal coding permits the representation of a given signal through the summation of sinusoids. The parameters of the sinusoids (the amplitudes, phases and frequencies) are transmitted to allow signal reconstruction. The sinusoidal parameters are sorted according to energy content and perceptual significance. The most significant parameters are transmitted first, allowing the use of only a small set of the parameters for signal reconstruction. The proposed scheme incurs a low delay …
Perfect Reconstruction Integer-Modulated Filter Banks, Alfred Mertins, T. Karp
Perfect Reconstruction Integer-Modulated Filter Banks, Alfred Mertins, T. Karp
Faculty of Informatics - Papers (Archive)
In this paper, we present design methods for perfect reconstruction (PR) integer-modulated filter banks, including biorthogonal (low-delay) filter banks. Both the prototype filter and the modulation sequences are composed of integers, thus allowing,efficient hardware implementations. To derive such filter banks, we first extend the PR conditions known for cosine modulation to other, more general, modulation schemes. We present solutions where the PR conditions on the prototype and the modulation are entirely decoupled and where some simple coupling is introduced. The conditions are derived for both even and odd numbers of channels. Design examples are presented for both cases.
Sew Representation For Low Rate Wi Coding, J. Lukasiak, I. S. Burnett
Sew Representation For Low Rate Wi Coding, J. Lukasiak, I. S. Burnett
Faculty of Informatics - Papers (Archive)
This paper considers low-rate waveform interpolation (WI) coding. It compares the existing, common slowly evolving waveform (SEW) quantisation scheme with two new schemes for representing and quantising the SEW. The first scheme uses a minimum phase estimate to reconstruct the SEW whilst the second scheme uses a pulse model whose parameters are implicitly transmitted in the quantised rapidly evolving waveform (REW). These new schemes maintain or reduce the bit rate required for transmission of the SEW. Results indicate that, for low rate WI coding, necessarily coarse SEW magnitude spectrum quantisation limits the contribution of the SEW to perceptual quality. Perceptual …
Audio Coding Using Sorted Sinusoidal Parameters, Mohammed Raad, I. Burnett
Audio Coding Using Sorted Sinusoidal Parameters, Mohammed Raad, I. Burnett
Faculty of Informatics - Papers (Archive)
This paper describes a new audio coding scheme based on sinusoidal coding of signals. Sinusoidal coding permits the representation of a given signal through the summation of sinusoids. The parameters of the sinusoids (the amplitudes, phases and frequencies) are transmitted to allow the signal reconstruction. In the proposed scheme, the sinusoidal parameters are sorted according to energy content and perceptual significance. The most significant parameters are transmitted first allowing the use of only a small set of the parameters for signal reconstruction. The proposed scheme incurs a low delay and uses a 20 ms frame length. Results show that the …