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 ev...

Audio coding at very low bit rates requires very efficient evaluation of characteristics of the signal sources and of perceptual properties of the human ear. An overview of models for the signal source employed in different coding schemes is given. Some of the basic concepts for perceptual quantization and coding of model parameters are shown, including approaches for scaleability with respect ...

We developed a very low bit rate watercolor-like video form, which is constructed with a bi-level Y luminance component and a number of UV chrominance combinations. The bi-level Ycomponent outlines the features of an image and the UVcombinations describe the basic color information of the image. The UV combinations are dynamically chosen during encoding. The resultant video looks better than bi...

In order to obtain optimal visual quality while meeting the bit rate requirements, a video transcoder needs efficient rate-control with fine and dynamic adjustments. This paper proposes a new frequency domain complexity estimation scheme and an algorithm for adaptive bit allocation during transcoding. In conjunction with frame skipping mechanism, the proposed algorithm adaptively determines spa...

In this paper we present two methods of enhancing the eigen face approach for the compression of images of human faces. In earlier work, a series of image basis functions (eigen faces) is created using the KarhunenLoeve transform on a large set of face images (the training set). The image to be encoded can then be approximated by a linear combination of these basis functions. We propose a rever...

Traditional parametric coding of speech facilitates low rate but provides poor reconstruction quality because of the inadequacy of the model used. We describe how a WaveNet generative speech model can be used to generate high quality speech from the bit stream of a standard parametric coder operating at 2.4 kb/s. We compare this parametric coder with a waveform coder based on the same generativ...

Radiotelescope access to a certain part of the sky requires very low tracking rate in azimuth. At low rates, the magnitude of the dry rolling friction torques at the telescope wheels cause a nonsmooth azimuth motion and the limit cycling of a telescope, which, in turn, deteriorates its pointing precision. The improvement of the low-rate tracking pointing through the dither implementation is dis...

The paper considers the phase retrieval problem in N dimensional complex vector spaces. It provides two sets of deterministic measurement vectors which guarantee signal recovery for all signals, excluding only a specific subspace and a union of subspaces, respectively. A stable analytic reconstruction procedure of low complexity is given. Additionally it is proven that signal recovery from thes...

This paper presents a low-cost microgyroscope with a resolution in the rate-grade at atmospheric pressure, which is fabricated using a CMOS compatible nickel electroplating process. Angular rate resolution of the gyroscope is increased by matching the resonance frequencies of the drive and sense modes close to each other using symmetric suspensions and electrostatic frequency tuning; whereas, u...