Stefan Wabnik

Learn More
Due to the demographic change, the number of older people will grow steadily within the next decades [1]. Technical systems, methods and algorithms developed in the context of Ambient Assisted Living (AAL) aim to enable these people to live self-determined and safe in their own homes as long as possible. To ensure this, these homes may have to be equipped(More)
Worldwide, ageing societies are bringing challenges for independent living and healthcare. Health-enabling technologies for pervasive healthcare and sensor-enhanced health information systems offer new opportunities for care. In order to identify, implement and assess such new information and communication technologies (ICT) the 'Lower Saxony Research(More)
Many societies across the world are confronted with demographic changes, usually related to increased life expectancy and, often, relatively low birth rates. Information and communication technologies (ICT) may contribute to adequately support senior citizens in aging societies with respect to quality of life and quality and efficiency of health care(More)
The paper presents a comparison of a previous and a new approach to shape quantization noise in low bit rate predictive audio coding. The previous approach uses an adaptation of the step size of a uniform quantizer, the new approach uses a quantizer with clipping. Both approaches are evaluated using a predictive audio coding scheme. The presented results of(More)
In this paper we present and evaluate several concealment strategies for packet losses in the context of a low delay predictive audio coder. Our goal is to minimize the audible impact of a packet loss. The problem is that the predictive coder is backward adaptive, hence depending on past values. There is a predictor reset, but to increase coding efficiency,(More)
The goal of the schemes we present in this paper is to obtain an ultra low delay audio coder with a good performance even at low bit rates (around 64 kb/s). The problem to be solved is to gain sufficient frequency resolution at low frequencies for precise low frequency psycho-acoustics and quantization noise shaping, because the ear has a higher frequency(More)
This paper compares two prediction structures for predictive perceptual audio coding in the context of the Ultra Low Delay (ULD) coding scheme. One structure is based on the commonly used AR signal model, leading to an IIR predictor in the decoder. The other structure is based on an MA signal model, leading to an FIR predictor in the decoder. We find that(More)
  • 1