Error robust low delay audio coding using spherical logarithmic quantization
Stephan Preihs, Timm Lamprecht, Jörn Östermann · 2016
This paper reveals the potential gain in audio quality that can be achieved by combining Spherical Logarithmic Quantization (SLQ) with advanced broadband error robust low delay audio coding based on ADPCM. We briefly summarize the basic properties and mechanisms of SLQ and the employed ADPCM scheme and show how they can be combined in a freely parameterizable coding algorithm. The resulting codec includes techniques for error robustness and a shaping of the coding noise. We present results of optimizing the codec parameters in our framework for global optimization based on psychoacoustic measures. Our evaluation shows that by using SLQ instead of scalar quantization a PEAQ ODG-score improvement with a maximum of about 1 point and a mean of 0.2 can be achieved. An analysis of the bit-error behavior of the combined SLQ-ADPCM shows that a major improvement in bit-error performance results from our proposed efficient error detection and processing.