MP3 compression of Doppler ultrasound signals

Poepping, Tamie L.; Gill, Jeremy; Fenster, Aaron; Holdsworth, David W.

doi:10.1016/S0301-5629(02)00696-8

« Previous Next »Ultrasound in Medicine and Biology
Volume 29, Issue 1 , Pages 65-76, January 2003

MP3 compression of Doppler ultrasound signals

Tamie L. Poepping
- Dr. Poepping’s present address is: Medical Physics, University of Edinburgh, Chancellor’s Building, 49 Little France Crescent, Edinburgh, EH16 4SA, UK.
- The John P. Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
Jeremy Gill
- The John P. Robarts Research Institute, London, Ontario, Canada
- Department of Physics and Astronomy, The University of Western Ontario, London, Ontario, Canada
Aaron Fenster
- The John P. Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
- Department of Diagnostic Radiology and Nuclear Medicine, The University of Western Ontario, London, Ontario, Canada
David W. Holdsworth
- The John P. Robarts Research Institute, London, Ontario, Canada
- Department of Medical Biophysics, The University of Western Ontario, London, Ontario, Canada
- Department of Diagnostic Radiology and Nuclear Medicine, The University of Western Ontario, London, Ontario, Canada
- Address correspondence to D. W. Holdsworth, Imaging Research Laboratories, The John P. Robarts Research Institute, 100 Perth Drive, P.O. Box 5015, London, Ontario, N6A 5K8, Canada

Received 6 February 2002; accepted 11 September 2002.

Abstract

The effect of lossy, MP3 compression on spectral parameters derived from Doppler ultrasound (US) signals was investigated. Compression was tested on signals acquired from two sources: 1. phase quadrature and 2. stereo audio directional output. A total of 11, 10-s acquisitions of Doppler US signal were collected from each source at three sites in a flow phantom. Doppler signals were digitized at 44.1 kHz and compressed using four grades of MP3 compression (in kilobits per second, kbps; compression ratios in brackets): 1400 kbps (uncompressed), 128 kbps (11:1), 64 kbps (22:1) and 32 kbps (44:1). Doppler spectra were characterized by peak velocity, mean velocity, spectral width, integrated power and ratio of spectral power between negative and positive velocities. The results suggest that MP3 compression on digital Doppler US signals is feasible at 128 kbps, with a resulting 11:1 compression ratio, without compromising clinically relevant information. Higher compression ratios led to significant differences for both signal sources when compared with the uncompressed signals. (E-mail: david.holdsworth@imaging.robarts.ca)

Keywords: MPEG-1 Layer 3, MP3 compression, Pulsed Doppler ultrasound, Directional audio signal, Phase quadrature signal, Peak velocity, Mean velocity, Spectral width, Doppler spectral power, Carotid bifurcation, Pulsatile flow