Heiko
Purnhagen
 
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Signal Processing

Biography

Heiko Purnhagen was born in 1969 in Bremen, Germany. He received the M.S. degree (Dipl.-Ing.) in Electrical Engineering from the University of Hannover, Germany, in 1994, concluded by a final thesis project on Automatic Speech Recognition carried out at the Norwegian Institute of Technology, Trondheim, Norway. From 1996 to 2002, he was with the Information Technology Laboratory at the University of Hannover, where he worked on very low bit rate audio coding using parametric signal representations, and where he received the PhD degree (Dr.-Ing.) in 2008.

In 2002, he joined Coding Technologies (now Dolby Sweden) in Stockholm, Sweden, where he is working on research, development, and standardization of perceptual low bit rate audio and speech coding systems and related signal processing algorithms. He contributed to the development of parametric techniques for efficient coding of stereo and multichannel signals, and his recent research activities include work on the unified coding of speech and audio signals, on signal enhancement algorithms, and on audio communication systems.

From 1996 to 2011, he was an active member of the ISO MPEG standardization committee and editor or co-editor of several MPEG standards. He is the principal author of the MPEG-4 parametric audio coding specification known as HILN (Harmonic and Individual Lines plus Noise) and contributed to the standardization of MPEG-4 High Efficiency AAC, the MPEG-4 Parametric Stereo coding tool, MPEG Surround, and MPEG Unified Speech and Audio Coding (USAC).

Dr. Purnhagen is a member of the AES and a senior member of the IEEE, has published many papers on low bit rate audio coding and related subjects, and has received numerous patents. He enjoys listening to live performances of jazz and free improvised music, and tries to capture them in his concert photography.

Contact

e-mail:  mail@heikopurnhagen.net
web:  www.heikopurnhagen.net/sigproc - this page
AES:  www.aes.org/member/profile.cfm/heikopurnhagen
LinkedIn:  www.linkedin.com/in/heikopurnhagen


Publications

Overview

Books and Book Chapters

H. Purnhagen,
Very low bit rate parametric audio coding,
Dissertation, Universität Hannover, DE, 2008.  Abstract  Book  Slides

J. Herre and H. Purnhagen,
“General audio coding,”
in The MPEG-4 Book, F. Pereira and T. Ebrahimi, Eds., chapter 11. Prentice-Hall, Englewood Cliffs, NJ, US, 2002.  Info

Journal Papers

A.C. den Brinker, J. Breebaart, P. Ekstrand, J. Engdegård, F. Henn, K. Kjörling, W. Oomen, and H. Purnhagen,
“An Overview of the Coding Standard MPEG-4 Audio Amendments 1 and 2: HE-AAC, SSC, and HE-AAC v2,”
EURASIP Journal on Audio, Speech, and Music Processing, Volume 2009, Article ID 468971, 21 pages, 2009, doi:10.1155/2009/468971.  Abstract  Paper

J. Herre, K. Kjörling, J. Breebaart, C. Faller, S. Disch, H. Purnhagen, J. Koppens, J. Hilpert, J. Rödén, W. Oomen, K. Linzmeier, and K. S. Chong,
“MPEG Surround - The ISO/MPEG standard for efficient and compatible multichannel audio coding,”
J. Audio Eng. Soc., Vol. 56, no. 1, pp. 932-955, Nov. 2008.  Abstract

A. Woywodt, A. Herrmann, J. T. Kielstein, H. Haller, M. Haubitz, and H. Purnhagen,
“A novel multimedia tool to improve bedside teaching of cardiac auscultation,”
Postgraduate Medical Journal, vol. 80, pp. 355-357, June 2004.  Abstract

H. Purnhagen,
“Der MPEG-4 Audio Standard - ein Überblick,”
Rundfunktechnische Mitteilungen (RTM), vol. 44, no. 2, Apr. 2000.  Abstract

Conference Papers

M. Neuendorf, M. Multrus, N. Rettelbach, G. Fuchs, J. Robilliard, J. Lecomte, S. Wilde, S. Bayer, S. Disch, C. Helmric, R. Lefebvre, P. Gournay, B. Bessette, J. Lapierre, K. Kjörling, H. Purnhagen, L. Villemoes, W. Oomen, E. Schuijers, K. Kikuiri, T. Chinen, T. Norimatsu, C. Kok Seng, E. Oh, M. Kim, S. Quackenbush, B. Grill,
“MPEG Unified Speech and Audio Coding—The ISO/MPEG Standard for High-Efficiency Audio Coding of All Content Types,”
in AES 132nd Convention, Budapest, HU, Apr. 2012.  Info

C. Helmrich, P. Carlsson, S. Disch; B. Edler, J. Hilpert, M. Neusinger, H. Purnhagen, N. Rettelbach, J. Robilliard, L. Villemoes,
“Efficient transform coding of two-channel audio signals by means of complex-valued stereo prediction,”
in Proc. IEEE Int. Conf. Acoustics, Speech, Signal Processing (ICASSP), Prague, CZ, May 2011, ASSP-P10.40.  Info

J. Engdegård, C. Falch, O. Hellmuth, J. Herre, J. Hilpert, A. Hölzer, J. Koppens, H. Mundt, H.-O. Oh, H. Purnhagen, B. Resch, L. Terentiev, M.L. Valero, L. Villemoes,
“MPEG Spatial Audio Object Coding—The ISO/MPEG Standard for Efficient Coding of Interactive Audio Scenes,”
in AES 129th Convention, San Francisco, CA, US, Nov. 2010, Preprint 8264.  Abstract

M. L. Valero, A. Hölzer, M. Schnell, J. Hilpert, M. Lutzky, J. Engdegård, H. Purnhagen, P. Ekstrand, K. Kjörling
“A New Parametric Stereo and Multichannel Extension for MPEG-4 Enhanced Low Delay AAC (AAC-ELD),”
in AES 128th Convention, London, UK, May 2010, Preprint 8099.  Abstract

J. Rödén, J. Breebaart, J. Hilpert, H. Purnhagen, E. Schuijers, J. Kippens, K. Linzmeier, A. Hölzer,
“A Study of the MPEG Surround Quality Versus Bit-Rate Curve,”
in AES 123rd Convention, New York, NY, US, Oct. 2007, Preprint 7219.  Abstract

H. Purnhagen, A. Ehret, J. Rödén, A. Gröschel,
“A novel approach to up-mix stereo to surround based on MPEG Surround technology,”
in AES 122nd Convention, Vienna, AT, May 2007, Preprint 6991.  Abstract

A. Ehret, A. Gröschel, H. Purnhagen, J. Rödén,
“Coding of "2+2+2" surround sound content using the MPEG Surround standard,”
in AES 122nd Convention, Vienna, AT, May 2007, Preprint 6992.  Abstract

J. Herre, K. Kjörling, J. Breebaart, C. Faller, S. Disch, H. Purnhagen, J. Koppens, J. Hilpert, J. Rödén, W. Oomen, K. Linzmeier, K. S. Chong,
“MPEG Surround - the ISO/MPEG standard for efficient and compatible multi-channel audio coding,”
in AES 122nd Convention, Vienna, AT, May 2007, Preprint 7084.  Abstract

J. Breebaart, J. Herre, C. Faller, J. Rödén, F. Myburg, S. Disch, H. Purnhagen, G. Hotho, M. Neusinger, K. Kjörling, W. Oomen,
“MPEG Spatial Audio Coding / MPEG Surround: overview and current status,”
in AES 119th Convention, New York, NY, US, Oct. 2005, Preprint 6599.  Abstract

L. Villemoes, J. Herre, J. Breebaart, G. Hotho, S. Disch, H. Purnhagen, K. Kjörling,
“MPEG Surround: The forthcoming ISO standard for spatial audio coding,”
in Proc. AES 28th Int. Conf., Piteå, SE, June 2006.  Abstract

J. Herre, H. Purnhagen, J. Breebaart, C. Faller, S. Disch, K. Kjörling, E. Schuijers, J. Hilpert, F. Myburg,
“The reference model architecture for MPEG spatial audio coding,”
in AES 118th Convention, Barcelona, ES, May 2005, Preprint 6447.  Abstract

A. Ehret, H. Hörich, K. Kjörling, H. Purnhagen, J. Rödén,
“aacPlus, only a low-bitrate codec?,”
in AES 117th Convention, San Francisco, CA, US, Oct. 2004, Preprint 6199.  Abstract

H. Purnhagen,
“Low complexity parametric stereo coding in MPEG-4,”
in Proc. Digital Audio Effects Workshop (DAFX), Naples, IT, Oct. 2004, pp. 163-168.  Abstract  Paper

E. Schuijers, J. Breebaart, H. Purnhagen, J. Engdegård,
“Low complexity parametric stereo coding,”
in AES 116th Convention, Berlin, DE, May 2004, Preprint 6073.  Abstract

J. Engdegård, H. Purnhagen, J. Rödén, L. Liljeryd,
“Synthetic ambience in parametric stereo coding,”
in AES 116th Convention, Berlin, DE, May 2004.  Abstract

M. Wolters, K. Kjörling, D. Homm, H. Purnhagen,
“A closer look into MPEG-4 High Efficiency AAC,”
in AES 115th Convention, New York, NY, US, Oct. 2003, Preprint 5871.  Abstract

H. Purnhagen,
“Parameter estimation and tracking for time-varying sinusoids,”
in Proc. 1st IEEE Benelux Workshop on Model based Processing and Coding of Audio (MPCA-2002), Leuven, BE, Nov. 2002, pp. 5-8.  Paper

N. Meine and H. Purnhagen,
“Fast sinusoid synthesis for MPEG-4 HILN parametric audio decoding,”
in Proc. Digital Audio Effects Workshop (DAFX), Hamburg, DE, Sept. 2002.  Paper

H. Purnhagen, N. Meine, B. Edler,
“Sinusoidal coding using loudness-based component selection,”
in Proc. IEEE Int. Conf. Acoustics, Speech, Signal Processing (ICASSP), Orlando, FL, US, May 2002, pp. II-1817 - II-1820.  Abstract

H. Purnhagen, B. Edler, N. Meine,
“Error protection and concealment for HILN MPEG-4 parametric audio coding,”
in AES 110th Convention, Amsterdam, NL, May 2001, Preprint 5300.  Abstract

H. Purnhagen, N. Meine, B. Edler,
“Speeding up HILN - MPEG-4 parametric audio encoding with reduced complexity,”
in AES 109th Convention, Los Angeles, CA, US, Sept. 2000, Preprint 5177.  Abstract

B. Edler and H. Purnhagen,
“Parametric audio coding,”
in Proc. International Conference on Signal Processing (ICSP2000), Beijing, CN, Aug. 2000.  Abstract

H. Purnhagen and N. Meine,
“HILN - the MPEG-4 parametric audio coding tools,”
in Proc. IEEE Int. Symposium on Circuits and Systems (ISCAS), Geneva, CH, May 2000, pp. III-201 - III-204.  Abstract

H. Purnhagen,
“Advances in parametric audio coding,”
in Proc. IEEE Workshop on Applications of Signal Processing to Audio and Acoustics (WASPAA), Mohonk, New Paltz, NY, US, Oct. 1999, pp. 31-34.  Abstract

H. Purnhagen,
“An overview of MPEG-4 audio version 2,”
in Proc. AES 17th Int. Conf. (High-Quality Audio Coding), Florence, IT, Sept. 1999, pp. 157-168.  Abstract

B. Edler and H. Purnhagen,
“Concepts for hybrid audio coding schemes based on parametric techniques,”
in AES 105th Convention, San Francisco, CA, US, Sept. 1998, Preprint 4808.  Abstract

H. Purnhagen, B. Edler, C. Ferekidis,
“Object-based analysis/synthesis audio coder for very low bit rates,”
in AES 104th Convention, Amsterdam, NL, May 1998, Preprint 4747.  Abstract

H. Purnhagen and B. Edler,
“Objektbasierter Analyse/Synthese Audio Coder für sehr niedrige Datenraten,”
in ITG-Fachtagung 'Codierung für Quelle, Kanal und Übertragung', Aachen, DE, Mar. 1998, pp. 35-40.  Info

B. Edler, H. Purnhagen, C. Ferekidis,
“ASAC - analysis/synthesis audio codec for very low bit rates,”
in AES 100th Convention, Copenhagen, DK, May 1996, Preprint 4179.  Abstract

T. Svendsen, F. K. Soong, H. Purnhagen,
“Optimizing baseforms for HMM-based speech recognition,”
Proc. EUROSPEECH, Sept. 1995.  Abstract

Patents

In addition to the granted patents listed below, there are further pending patents.

E. Schuijers, G. Hotho, H. Purnhagen, W. Schildbach, H. Hoerich, K. Kjoerling, J. Roeden,
Audio decoding,
EP2088580, granted 2011.  Info

J. Hilpert, K. Linzmeier, J. Herre, R. Sperschneider, A. Hölzer, L. Villemoes, J. Engdegard, H. Purnhagen, K. Kjörling, J. Breebaart, W. Oomen
Apparatus and method for multi -channel parameter transformation,
EP2082397, granted 2011.  Info

A. Biswas, H. Purnhagen, K. Kjörling, B. Resch, L. Villemoes, P. Hedelin,
Audio encoder and decoder,
EP2077551, granted 2011.  Info

J. Engdegard, L. Villemoes, H. Purnhagen, B. Resch,
Enhanced coding and parameter representation of multichannel downmixed object coding,
EP2068307, granted 2011.  Info

J. Engdegård, L. Villemoes, H. Purnhagen, B. Resch,
Enhanced coding and parameter representation of multichannel downmixed object coding,
EP2054875, granted 2011.  Info

E. Schuijer, G. Hotho, H. Purnhagen, W. Schildbach, H. Hörich, K. Kjörling, J. Rödén,
Audio encoding and decoding,
EP1902443, granted 2009.  Info

G. Hotho, J. Breebaart, E. Schuijers, B. den Brinker, L. Villemoes, H. Purnhagen, J. Rödén,
Multi-channel audio coding,
EP1866912, granted 2010.  Info

K. Kjörling, H. Purnhagen, J. Rödén, J. Engdegård,
Interpolation and signalling of spacial reconstruction parameters for multichannel coding and decoding of audio sources,
EP1807824, granted 2008.  Info

P. Ekstrand, L. Villemoes, H. Purnhagen,
Partially complex modulated filter bank,
EP1789954, granted 2008.  Info

H. Purnhagen, J. Breebaart, E. Schuijers, L. Villemoes, J. Rödén, J. Engdegård,
Stereo compatible multi-channel audio coding,
EP1784819, granted 2008.  Info

M. van Loon, J. Breebaart, G. Hotho, E. Schuijers, H Purnhagen, J. Rödén
Method, device, encoder apparatus, decoder apparatus and audio system,
EP1769655, granted 2011.  Info

J. Breebaart, E. Schuijers, H. Purnhagen, J. Rödén,
Audio channel conversion,
EP1769491, granted 2009.  Info

J. Rödén, J. Engdegård, H. Purnhagen, J. Breebaart, E. Schuijers, S. van de Par, J. Hilpert, J. Herre,
Energy dependent quantization for efficient coding of spatial audio parameters,
EP1754222, granted 2007.  Info

L. Villemoes, K. Kjörling, H. Purnhagen, J. Rödén, J. Breebaart, G. Hotho,
Multi parameterization based multi-channel reconstruction,
EP 1738353, granted 2007.  Info

H. Purnhagen, L. Villemoes, J. Engdegård, J. Rödén, K. Kjörling,
Method for representing multi-channel audio signals,
EP1735775, granted 2007.  Info

L. Villemoes, K. Kjörling, H. Purnhagen, J. Rödén, J. Breebaart, G. Hotho,
Multi-channel audio energy loss compensation,
EP1730726, granted 2007.  Info

H. Purnhagen, L. Villemoes, J. Engdegård, J. Rödén, K. Kjörling,
Apparatus and method for generating a level parameter and apparatus and method for generating a multi-channel representation,
EP1695338, granted 2007.  Info

L. Villemoes, P. Ekstrand, H. Purnhagen, E. Schuijers, F. de Bont,
Audio signal encoding or decoding,
EP1683133, granted 2007.  Info

N. Meine, H. Purnhagen,
Method and device for coding/decoding,
EP1206840, Granted 2003.  Info

Talks

H. Purnhagen,
Audio Coding - Overview and Latest Developments in MPEG-4,
presented at Medieteknikdagarna Norrköping, SE, April 1, 2004.  Info  Abstract

H. Purnhagen,
Parametric Audio Coding in MPEG-4,
presented at NTNU, Trondheim, NO, April 25, 2001.  Abstract  Slides

H. Purnhagen,
Parametrische Audiocodierung in MPEG-4,
präsentiert im Rahmen der Vortragsreihe 'Media Event' an der TU Ilmenau, Ilmenau, DE, Dezember 12, 2000.  Abstract  Slides

H. Purnhagen, B. Edler,
Perceptual Audio Coders - What to listen for: Artifacts of Parametric Coding,
presented at Workshop W9 "Perceptual Audio Coders - What to listen for", 109th AES Convention, Los Angeles, Sept. 2000,
revised version presented at Workshop W4 "Listening to Perceptual Audio Coders", 112th AES Convention, Munich, May 2002.  Abstract  Slides

B. Edler, H. Purnhagen,
Perceptual Audio Coders - What to listen for: Speech Codecs and Music,
presented at Workshop W9 "Perceptual Audio Coders - What to listen for", 109th AES Convention, Los Angeles, Sept. 2000,
revised version presented at Workshop W4 "Listening to Perceptual Audio Coders", 112th AES Convention, Munich, May 2002.  Abstract  Slides

H. Purnhagen,
MPEG-4 Version 2 Audio Workshop: HILN - Parametric Audio Coding,
presented at Workshop W3 "MPEG-4 Version 2 Audio ­ What is it about?", 108th AES Convention, Paris, February 2000.  Abstract  Slides

H. Purnhagen,
Überblick über MPEG-4 Audio Version 2,
präsentiert auf der ITG-Diskussionssitzung "Stand der Audiocodierung heute", Institut für Rundfunktechnik, München, November 1999.  Abstract  Slides

H. Purnhagen,
Parametrische Audiocodierung bei sehr niedrigen Datenraten,
präsentiert auf der ITG-Diskussionssitzung "Stand der Audiocodierung heute", Institut für Rundfunktechnik, München, November 1999.  Abstract  Slides

Other Publications

Editor or co-editor of several parts of MPEG standards, including ISO/IEC 14496-3 (MPEG-4 Audio) and ISO/IEC 23003-1 (MPEG Surround).

H. Purnhagen and B. Edler,
“Speech Coding Artifacts,”
in Perceptual Audio Coders: What to Listen For, AES Tutorial CD-ROM, 2001.  Info

H. Purnhagen,
Some mathematics behind multi-channel prediction, Internal Technical Memo, Universität Hannover, Institut für Theoretische Nachrichtentechnik und Informationsverarbeitung, Sept. 1994.  Abstract  Paper

H. Purnhagen,
N-best search methods applied to speech recognition,
Diploma thesis (Diplomarbeit), Universitetet i Trondheim, Norges Tekniske Høgskole, Institutt for Teleteknikk, May 1994.  Abstract  Thesis

H. Purnhagen,
Implementation und Untersuchung eines Verfahrens zur Reduktion der Stereo-Redundanz bei der Codierung von Audiosignalen,
Thesis (Studienarbeit), Universität Hannover, Institut für Theoretische Nachrichtentechnik und Informationsverarbeitung, Dec. 1992.  Abstract  Thesis

H. Purnhagen,
Digitaler Synthesizer II,
Wettbewerbsbeitrag (Technik), Jugend Forscht, 1987.  Wettbewerbsbeitrag

H. Purnhagen,
Digitaler Synthesizer,
Wettbewerbsbeitrag (Technik), Jugend Forscht, 1986.  Wettbewerbsbeitrag

H. Purnhagen,
“ELO-Computing: 1-Bit-Spracherkennung (2)”,
in ELO - Das Magazin für Elektronik und Computer, 7/1986, Seite 60-62, Franzis-Verlag München, Juli 1986.

H. Purnhagen, B. Eder,
“ELO-Computing: 1-Bit-Spracherkennung (1)”,
in ELO - Das Magazin für Elektronik und Computer, 6/1986, Seite 40-43, Franzis-Verlag München, Juni 1986.

H. Purnhagen,
1-Bit-Spracherkennung,
Wettbewerbsbeitrag (Technik), Jugend Forscht, 1985.  Wettbewerbsbeitrag

H. Purnhagen,
“Jugend forscht: Spektrometer im Selbstbau”,
in LC - Lehrmittel Computer (Zeitschrift für die Schulpraxis und Weiterbildung), 2.85, Seite 29-31, Westermann, Mai 1985.

H. Purnhagen,
Spektrometer mit Microcomputersteuerung und -Auswertung,
Wettbewerbsbeitrag (Physik), Jugend Forscht, 1984.  Wettbewerbsbeitrag

H. Purnhagen,
Bau eines Ultraschall-Radargerätes mit zweidimensionaler Echodarstellung auf einem Computerbildschirm,
Wettbewerbsbeitrag (Physik), Jugend Forscht, 1983.  Wettbewerbsbeitrag

H. Purnhagen,
Bau eines Plotters aus Fischer-Technik und Erstellung von Demonstrationsprogrammen in Basic für den Betrieb des Plotter,
Wettbewerbsbeitrag (Technik), Jugend Forscht, 1982.  Wettbewerbsbeitrag

H. Purnhagen,
Glücksspielautomat mit Münzprüfer und Gewinnausgabe,
Wettbewerbsbeitrag (Technik), Jugend Forscht, 1981.  Wettbewerbsbeitrag

H. Purnhagen,
Erarbeitung von Gewinnstrategien für das Spiel "Mühle",
Wettbewerbsbeitrag (Mathematik/Informatik), Jugend Forscht, 1980.  Wettbewerbsbeitrag