Method and apparatus for synchronizing audio and video in encrypted videoconferences
View Patent ↗The invention provides a system that preserves the synchronization of the audio and video presented at a secure conferencing site without necessitating decryption, decompression, compression, and encryption of signals at the hub. The presently preferred embodiment of the invention provides an apparatus and method for synchronizing audio and video in encrypted videoconferences that comprises a plurality of conference sites; and a hub for receiving a compressed and encrypted, composite audio and video signal from each site, for determining a currently active site, and for transmitting said composite audio and video signal from said currently active site to all other sites; said hub receiving a compressed and encrypted audio only signal from each site; wherein said hub routes all incoming compressed and encrypted audio only signals to each site.
1. An apparatus for synchronizing audio and video in videoconferences, comprising:
a plurality of conference sites; and
a hub for receiving a composite audio and video signal from each site, determining for each site a currently displayed composite audio and video signal, and transmitting said currently displayed composite audio and video signal to each of said sites;
said hub receiving an audio only signal, separate from said received composite audio and video signal, from each site; and
wherein said hub routes all incoming received audio only signals to each site separately from said transmitted composite audio and video signal;
each site comprising:
an audio deselection and mixing device for deselecting an audio only signal corresponding to an audio portion of said currently displayed composite audio and video signal, and for mixing said audio portion of said composite audio and video signal for said currently active site with all other audio only signals at said site;
wherein audio associated with displayed video is synchronized with said displayed video.
2. The apparatus of claim 1 , wherein said audio only signal for a site comprises:
a mixed audio signal composed of audio obtained from several microphones at said site.
3. The apparatus of claim 1 , wherein said composite audio and video signals are encrypted.
4. The apparatus of claim 1 , wherein said composite audio and video signals are compressed.
5. The apparatus of claim 1 , wherein said composite audio and video signals are both encrypted and compressed.
6. The apparatus of claim 5 , each site comprising:
a decoder for decrypting and decompressing video within said currently displayed composite audio and video signal.
7. The apparatus of claim 1 , wherein said audio only signal from each site is encrypted and compressed, each site comprising:
a decoder for decrypting and decompressing said compressed and encrypted audio only signal from each site.
8. The apparatus of claim 1 , said audio deselection and mixing device further comprising:
delay circuitry for aligning said audio only signals with said composite audio and video signal.
9. The apparatus of claim 1 , wherein said hub transmits at least two composite audio and video signals to each site to provide a split screen display at each site.
10. The apparatus of claim 9 , wherein those of said audio only signals which correspond to said at least two composite audio and video signals are deselected at each said site.
11. The apparatus of claim 1 , further comprising:
an audio deselection hub for deselecting those audio only signals not directly associated with an ongoing conversation.