Synchronizing Input Streams for Acoustic Echo Cancellation

Abstract

Input streams for acoustic echo cancellation are associated with timestamps using reference times from a common clock. A render delay occurs between when an inbound signal is written to a buffer and when it is retrieved for rendering. A capture delay occurs between when a capture signal is written to a buffer and when it is retrieved for transmission. Both the render delay and the capture delay are variable and independent of one another. A render timestamp applies the render delay as an offset to a reference time at which the inbound signal is written to the buffer for rendering. A capture timestamp applies the capture delay as an offset to a reference time at which when the capture signal is retrieved for transmission. Applying the delay times as offsets to the reference times from the common clock facilitates synchronizing the streams for echo cancellation.

Dependencies are inferred from the claim text.