AES Vienna 2007: Paper Session P4

P4 - Audio Archiving, Storage, Restoration, and Content Management

Saturday, May 5, 14:00 — 18:30

Chair: Dietrich Schüller, Austrian Academy of Sciences - Vienna, Austria

P4-1 Sound Archiving—A Challenge for the Audio Engineering Society [Invited Paper]—Dietrich Schuller, Phonogrammarchiv Vienna - Vienna, Austria

P4-2 150 Years of Time-Base in Acoustic Measurement and 100 Years of Audio's Best Publicity Stunt—2007 as a Commemorative Year—George Brock-Nannestad, Patent Tactics - Gentofte, Denmark
Léon Scott's invention of the phonoautograph in 1857 made a long time-base available for recording of vibrations, and it was also the first time an air-borne sound was recorded. Although his invention formed the basis, both for sound recording and reproduction and for acoustical science as we know it, it has been largely forgotten. Neither Scott nor the instrument maker Koenig are mentioned in the series “Benchmark Papers of Acoustics.” Today we take sound archives for granted, but the whole sound archive movement would not have received any attention in the general public, if one particular event had not occurred: the sealed deposit in 1907 of important shellac records and a gramophone in the vaults below the Paris Opera house. They were intended to remain untouched for 100 years, and they have survived to this day. The paper will provide the documentation for these historical events that form the basis of so many of our professional activities.
Convention Paper 7007 (Purchase now)

P4-3 Knowledge: The Missing Element in Archiving and Restoration? —Sean W. Davies, SW Davies, Ltd. - Aylesbury, UK
This admittedly provocative title nevertheless calls attention to a situation that already exists and may become critical in the future. No sound recording can be considered in isolation from the technical system that produced it. A proper working knowledge of such a system is an essential requirement for any person working on the transfer of such a recording. This paper examines the range of such required knowledge and the means by which it may be taught to personnel likely to be involved with archival material.
Convention Paper 7008 (Purchase now)

P4-4 Noncontact Phonographic Disk Digitization Using Structured Color Illumination—Louis Laborelli, Jean-Hugues Chenot, Alain Perrier, INA (Institut National de l'Audiovisuel) - Bry sur Marne, France
We propose an innovative contact-less optical playing device for 78 rpm and 33 rpm lateral modulation phonographic disks using structured color illumination. An area of the disk is illuminated by a beam of rays, with color depending on the direction of incidence, that are reflected by the groove wall toward a camera image. In contrast with standard methods that measure the velocity of the groove at a single location, direct access to the audio signal value is obtained here directly from pictures through color decoding, and the whole height of the groove wall is exploited. This color coding allows for the detection of occluding dust and automated interpolation of the missing audio signal. Results on distortion, S/N ratio, and bandwidth are presented.
Convention Paper 7009 (Purchase now)

P4-5 Improvement of Cylindrical Record Reproduction Utilizing Inharmonic Frequency Analysis GHA—Teruo Muraoka, Shota Nakagomi, Tohru Ifukube, University of Tokyo - Tokyo, Japan
Cylindrical records were important sound media around the beginning of 20th century, and a lot of historical recordings were made by using them. We have engaged in the research of cylindrical record reproduction and noise-reduction of damaged SP records utilizing inharmonic frequency analysis of GHA (Generalized Harmonic Analysis). Surface noise of cylindrical records are more serious than SP records, so we challenged its noise reduction by modifying GHA noise-reduction.
Convention Paper 7010 (Purchase now)

P4-6 Method Comparison of Pick-Up and Preprocessing of Bias Signal for Wow and Flutter Correction—Nadja Wallaszkovits, Franz Pavuza, Phonogrammarchiv Austrian Academy of Sciences - Vienna, Austria; Heinrich Pichler, Audio Consultant - Vienna, Austria
This paper discusses the practical implementation of high frequency bias signal retrieval from analog magnetic tapes at original replay speeds by using slightly modified standard playback facilities. Based on an implementation within an archival workflow and prior studies of bias signal retrieval from analog magnetic tape, the authors focus on a comparison of reproduction and preprocessing methods of the bias signal. Previous approaches are compared to the authors’ proposed method. The signal preprocessing in the analog as well as digital domain is outlined and, based on analyses of bias signals from professional and semi-professional recordings, the various practical problems are discussed: level instability and unknown frequency of the recorded bias signal, frequency variations mainly with semiprofessional devices of older types of recording equipment due to the instability of the bias oscillator, as well as effects of signal distortions, interferences, signal aliasing problems, and ultrasonic artifacts. The practical applicability within a standard archival transfer is discussed.
Convention Paper 7011 (Purchase now)

P4-7 Improved Magneto-Optical ¼-Inch Audio Tape Player for Preservation—Marcel Guwang, Hi-Stor Technologies - Colomiers, France
This improved quarter-inch audio tape player features a multitrack magneto-optical reader to reduce preservation cost through speed, adjustment automation, and compatibility. The benefits of this 32-channel head, connected to a digital signal processor, are high speed capability, compatibility, and automatic detection of any number of audio tracks, real time automatic adjustment of the best digital playback azimuth, and filtering of crosstalk and partial track erasures.
Convention Paper 7012 (Purchase now)

P4-8 Analysis and Restoration of Faulty Audio CDs—Hélène Galiègue, Université Pierre et Marie Curie - Paris, France; Jean-Marc Fontaine, Laboratoire d'Acoustique Musicale - Paris, France; Laurent Daudet, Université Pierre et Marie Curie - Paris, France
Many audio CDs (mostly CD-Rs but also CD-ROMs) have defects that appear due to bad manufacturing, careless use, or simple aging of its physical constituents. Here, we study such audio CDs that are still readable with a standard player (computer CD/DVD drive or standalone audio player with digital output), but whose defects are not fully handled by error correction codes, resulting in a highly distorted signal. This paper is two-fold: first, we characterize these errors on a few example discs; and second, we study different means to restore the audio content, by fusion of multiple reads and interpolation schemes.
Convention Paper 7013 (Purchase now)

P4-9 Techniques for the Authentication of Digital Audio Recordings—Eddy B. Brixen, EBB-consult - Smørum, Denmark
In forensic audio one important task is the authentication of audio recordings. Standards and procedures already exists regarding analog recordings. In the field of digital recording and digital media the conditions are different. A rock solid methodology is needed here, but does not exist yet. This paper reviews existing techniques and presents some results regarding an additional number of tools, the ENF criterion, which should be considered to become a standard within the AES as well as in the forensic community as a whole.
Convention Paper 7014 (Purchase now)

P4-10 Using Multiple Feature Extraction with Statistical Models to Categorize Music by Genre—Benjamin Fields, Goldsmiths College, University of London - London, UK
In recent years, large capacity portable personal music players have become widespread in their use and popularity. Coupled with the exponentially increasing processing power of personal computers and embedded devices, the way people consume and listen to music is ever changing. To facilitate the categorization of these personal music libraries, a system is employed using MPEG-7 feature vectors as well as Mel-Frequency Cepstral Coefficients classified through multiple trained Hidden Markov Models and other statistical methods. The output of these models is then compared and a genre choice is made based on which model gives the best fit. Results from these tests are analyzed and ways to improve the performance of a genre sorting system are discussed.
Convention Paper 7015 (Purchase now)