John F. Arnold

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Audio-visual and other multimedia services are seen as important sources of traffic for future telecommunication networks, including wireless networks. A major drawback with some wireless networks is that they introduce a significant number of transmission errors into the digital bitstream. For video, such errors can have the effect of degrading the quality(More)
Widespread use of digital imagery has resulted in a need to manage large collections of images. Systems providing query by example (QBE) capability offer improved access to contents of image libraries by retrieving matches to a query image. Texture is an important feature to consider in the matching process. However, standard approaches often employ a(More)
This paper describes a rate control algorithm for a variable bit-rate (VBR) video coder. The algorithm described varies the quantizer step size of the coder according to properties of an image sequence that affect the perception of errors. The algorithm also limits the output bit-rate of the coder without the use of buffers to more efficiently use network(More)
Image segmentation can be viewed as the process of classifying regions in a picture into groups with common properties (e.g., texture). A difficulty arising is that a common texture can be classified differently when viewed at different scales and rotated viewpoints. The paper presents a feature vector based on the DT-CWT (dual-tree complex wavelet(More)
We investigate the problem of robust video transmission over packet loss networks. A resilient video coding framework is important to ensure quality video over these networks. We propose a combination of multiple description coding and an optimized packetization method to constitute the error resilient codec. Multiple description coding technique utilizes(More)
It is well known that tile-boundary artifacts occur in wavelet-based lossy image coding. However, until now, their cause has not been understood well. In this paper, we show that boundary artifacts are an inescapable consequence of the usual methods used to choose tile size and the type of symmetric extension employed in a wavelet-based image decomposition(More)
Signal-to-noise ratio (SNR) scalability has been incorporated into the MPEG–2 video-coding standard to allow for the delivery of two services with the same spatial and temporal resolution but different levels of quality. In this paper, we begin by reviewing the performance of a single-loop SNR scalable encoder that is compliant with the MPEG–2 standard and(More)