Hans L. Cycon

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In this paper, we propose a very low bit rate video coding scheme based on a discrete wavelet transform (DWT), block-matching motion estimation (BME) and overlapped block motion compensation (OBMC). Our approach reveals that the coding process works more eeciently if the quan-tized wavelet coeecients will be pre-processed by a mechanism exploiting the(More)
This paper describes a video coding algorithm that combines new ideas in motion estimation and wavelet-based coding techniques. A motion estimation technique using an image warping model is employed to reduce temporal redundancies in a given image sequence. The underlying continuous motion model is based on a bilin-ear warp of a grid of quadrangles. It has(More)
In this paper we present a new method to do automatic sleep stage classification. The algorithm consists of basically three modules. A wavelet packet transformation (WPT) is applied to 30 seconds long epochs of EEG recordings to provide localized time-frequency information, a feature generator which quantifies the information and reduce the data set size,(More)
This paper presents an algorithm for very low bit-rate video coding that combines new ideas in motion estimation, wavelet lter design, and wavelet-based coding techniques. A new motion compensation technique using image warping and overlapped block motion compensation is proposed to reduce temporal redundancies in a given image sequence. This combined(More)
In this paper, we propose a spatially adaptive wavelet thresholding method using a context model that has been inspired by our prior work on image coding. The proposed context model relies on an estimation of the weighted variance in a local window of scale and space. Appropriately chosen weights are used to model the predominant correlations for a reliable(More)
In this paper, we propose a very low bit-rate video coding scheme based on a discrete wavelet transform (DWT), block-matching motion estimation (BME), and overlapped block motion compensation (OBMC). Our approach reveals that the coding process works more efficiently if the quantized wavelet coefficients are preprocessed by a mechanism exploiting the(More)
In recent years the capabilities of the common Internet infrastructure have increased to an extent where data intensive communication services may mature to become popular, reliable applications. Videoconferencing over IP can be seen as such a highly prominent candidate. However, heavy infrastructure and complicated call handling hinder acceptance of(More)
The purpose of this paper is twofold: On the one hand, we propose a fast wavelet-based video codec which is implemented into a real-time video conferencing tool. The proposed codec uses temporal frame difference coding, a computationally low-complex 5/3 tap wavelet transform, and a fast entropy coding scheme based on Golomb-Rice codes. On the other hand, we(More)
A rapidly growing number of carriers offer wireless video services to their customers, taking advantage of high quality video codecs implemented in dedicated hardware of selected mobile devices. In this paper we introduce a video conferencing software, which seamlessly integrates mobile with stationary users in a provider and device independent fashion.(More)