Notes
Slide Show
Outline
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360 degrees video and audio recording and broadcasting employing a parabolic mirror camera and a spherical 32-capsules microphone array
  • Leonardo Scopece1, Angelo Farina2, Andrea Capra2


  • 1 RAI CRIT, Turin, ITALY
  • 2 University of Parma, ITALY
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The origin of a new multichannel shooting and recording system
  • The project was started by Rai Research Centre and Advanced Industrial Design in Acoustic (A.I.D.A.), spin-off of the University of Parma, in 2009


  • It resulted in the patent of an innovative system for live shooting and recording, called 3D Virtual Microphone System


  • Starting from a sperical microphone probe, the system can synthesize up to 7 virtual microphones, which can be moved in realtime, with variable directivity (zooming) capability
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Previous experience
  • At UNIPR-Aida we had 10 years of experience employing 1st-order Ambisonics microphones (Soundfield TM, DPA-4, Tetramic, Brahma)
  • At RAI-CRIT, the Holophone HD was employed as the stanadard microphone system for surround recording
  • Both systems were unsatisfactory in terms of spatial resolutiion and stability of the polar patterns with frequency
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Capturing Ambisonics signals
  • A tetrahedrical microphone probe was developed by Gerzon and Craven, originating the Soundfield microphone
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Soundfield microphones
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Soundfield Recordings
  • The Soundfield (TM) microphone provides 4 signals:
    1 omnidirectional (pressure, W) and 3 figure-of-8 (velocity, X, Y, Z)
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Directivity of transducers
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Computation of filter coefficients
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Computation of filter coefficients
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STEP2: Target Directivity
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Hardware for 360° video
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Video unwrapping
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Video Sample: ScreenRecording
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Video Sample: Parlato
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Video Sample: Arlecchino
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Example of post-processing with 7 fixed microphones
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Video Sample: Boheme
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Video Sample: Tchaikovsky
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First realtime broadcasting: 21 june 2011
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Lucia di Lammermoor
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Audio/Video Samples download
  • The audio/video samples employed during the presentation can be downloaded from


  • HTTP://pcfarina.eng.unipr.it/Public/EBU-2011