In this Letter we describe a beamforming video recorder consisting of a video camera at the center of a 16 hydrophone array. A broadband frequency-domain beamforming algorithm is used to estimate the azimuth and elevation of each detected sound. These estimates are used to generate a visual cue indicating the location of the sound source within the video recording, which is synchronized to the acoustic data. The system provided accurate results in both lab calibrations and a field test. The system allows researchers to correlate the acoustic and physical behaviors of marine mammals during studies of social interactions.

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See EPAPS Document No. EPAPS-JASMAN-117-705501 for downloadable files containing the video files showing the beamforming video recorder output as it tracks whistles and clicks from a dolphin and places a + cue on the video image based on the beamformed array data.
A direct link to this document may be found in the online article’s HTML reference section. The document may also be reached via the EPAPS homepage (http://www.aip.org/pubservs/epaps.html) or from ftp.aip.org in the directory /epaps. See the EPAPS homepage for more information.
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