Rate-distortion optimized quantization in multistage audio coding
2006 (English)In: Ieee Transactions on Audio Speech and Language Processing, ISSN 1558-7916, Vol. 14, no 1, 311-320 p.Article in journal (Refereed) Published
In this work, we develop a new method for quantization in multistage audio coding. Given a (perceptual) distortion measure and a bit-rate constraint, we analytically derive the optimal rate distribution between subcoders (stages) and the corresponding optimal quantizers using high-rate theory. The analytical solutions for optimal quantizers allow a coder to easily adapt to changes in bit-rate requirements. As an illustration of the new method, we consider quantization in a two-stage sinusoidal/wave form coder that is a widely used combination in audio coding. We show that at low total rates most of the rate should be assigned to the sinusoidal (model-based, subspace) subcoder, while at high total rates most of the rate should be assigned to the waveform (full-space) subcoder. We compare the new method to a reference quantization method that does not use rate-distortion optimization. A significantly higher performance of the new method is shown by means of a listening test.
Place, publisher, year, edition, pages
2006. Vol. 14, no 1, 311-320 p.
audio coding, high-rate theory, modified discrete cosine transform (MDCT), multistage coding, quantization, rate-distortion optimization, sinusoidal coding, waveform coding
IdentifiersURN: urn:nbn:se:kth:diva-15426DOI: 10.1109/tsa.2005.854104ISI: 000235369100030ScopusID: 2-s2.0-33744967700OAI: oai:DiVA.org:kth-15426DiVA: diva2:333467
QC 201005252010-08-052010-08-05Bibliographically approved