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AES Barcelona 2005
Paper Session K - Signal Processing, Part 1

Last Updated: 20050401, mei

Monday, May 30, 10:00 — 13:00

Chair: Vicki Melchior, Signal Processing Consultant - San Anselmo, CA, USA

K-1 Generalized Harmonic Analysis (GHA) and Its Application to Intensive Noise ReductionYoshihiro Kanda, Kiriu Shinya, Kenji Katayama, Teruo Muraoka, Musashi Institute of Technology - Setagaya-ku, Tokyo, Japan
GHA is an inharmonic frequency analysis proposed by N. Wiener and featured with its excellent frequency resolution. However, it has not been examined practically until we obtained quite powerful computers due to the difficulty of requiring a huge amount of calculations. Recently an elegant algorithm enabling the reduction calculations was announced by Dr. Hirata, and the authors have proved the algorithm profitable to practical applications. Consequently, it realized both processing speed and accuracy in practical stages. In order to utilize GHA’s advantages of precise frequency detection and separation, the authors have been trying to apply GHA to signal processing in audio engineering. Scratch noise reduction of damaged SP records will be reported as an example.
Convention Paper 6432 (Purchase now)

K-2 Efficient Error Vector Calculation in Affine Projection Algorithms for Active Noise ControlAlberto González, María de Diego, Miguel Ferrer, Gema Piñero, Universidad Politécnica de Valencia - Valencia, Spain
Adaptive affine projection (AP) algorithms show good trade-off between computational effort and convergence speed. Nevertheless, the computational complexity of the AP algorithms increases with the projection order. Therefore low-computational versions, named fast AP (FAP) algorithms, have been proposed for practical applications. In this paper an improved algorithm that uses fast error vector calculation is applied for active noise control (ANC). The proposed version is based on the filtered-x filtering configuration instead of the modified filtered-x one, which is the more commonly applied for the AP algorithm. A comparative practical study of the different filtering configurations and fast AP versions have been carried out in order to validate the use of the proposed method.
Convention Paper 6433 (Purchase now)

K-3 Challenges of Acoustic Echo Cancellation in Low Cost ApplicationsAlexander A. Goldin, Alango Ltd. - Haifa, Israel; Alexey Budkin, Alango Ltd. - St. Petersburg, Russia
The paper presents challenges of performing effective acoustic echo cancellation in time-delay sensitive applications where the quality of used acoustic components is low, the acoustic design may be pure, and the cost of used digital components must be reduced as low as possible. The situation is typical for mass-market applications such as mobile and regular telephones, office speakerphones, and low cost conferencing systems. Using low cost components in compact enclosures introduces large amounts of nonlinear distortions into the loudspeaker signal causing pure performance of classical acoustic echo cancellation algorithms. Unfortunately, more sophisticated algorithms require more processing power and larger processing delays. The paper discusses possible trade-offs as well as solutions implemented in the Alango Voice Communication Package.
Convention Paper 6434 (Purchase now)

K-4 An Efficient, Fine-Grain Scalable Audio Compression SchemeHuan Zhou, Alfred Mertins, Stefan Strahl, University of Oldenburg - Oldenburg, Germany
To address the fine-grain scalable audio compression issue, a novel combined significance tree technique is proposed for high compression efficiency. The core idea is to dynamically adopt a set of locally optimal significance trees instead of following the common approach of using a single type of tree. Two different encoding strategies are proposed: the spectral coefficients can be encoded either in a threshold-by-threshold manner or in a segment-by-segment manner. The former yields rate and fidelity scalability, and the latter additionally yields bandwidth scalability. Experimental results show that our proposed scheme significantly outperforms the existing schemes using single-type trees and performs comparably with the MPEG AAC coder while achieving fine-grain scalability.
Convention Paper 6435 (Purchase now)

K-5 Program Loudness: Nuts & BoltsJean Paul Moerman, VRT, Belgian National Broadcasters for the Flemish Community - Brussels, Belgium
Program loudness is still one of the topics of discussion between broadcasters. This paper is not another attempt to give explanation on the causes. Instead it is a practical guide how the problem for the viewer has been solved at VRT, Belgium’s National Broadcaster. Program makers are to be convinced of the importance of sound to get their message to the viewer. The technical management have to realize the necessity of processing units all over the production chain. Settings have to be carefully integrated throughout every department. How the settings are achieved and convincing the management is one of the many topics described in this practical paper.
Convention Paper 6436 (Purchase now)

K-6 Automated Speech/Other Discrimination for Loudness MonitoringMark Vinton, Charlie Robinson, Dolby Laboratories - San Francisco, CA, USA
Inter-program audio level discrepancies continue to plague the content creation and broadcast industries. In particular, end users are often compelled to make adjustments to audio playback levels. It has previously been established that leveling programs based on dialog loudness can improve listener satisfaction; however, it is difficult to measure as it requires a human to continuously monitor an audio stream and measure only the loudness during speech portions of the content. This paper presents an automated speech discrimination system that provides a means to detect portions of audio content that contain primarily speech. The speech/other discrimination system takes advantage of well known speech characteristics to achieve a total error of approximately 3.5 percent despite delay and computational limitations.
Convention Paper 6437 (Purchase now)

©2005 Audio Engineering Society, Inc.