公开(公告)号：WO2022170003A1

公开(公告)日：2022-08-11

申请号：PCT/US2022/015158

申请日：2022-02-03

Applicant: ZOOM VIDEO COMMUNICATIONS, INC.

Inventor： RAO, Yu ,  WANG, Yangzhong ,  LI, Jianglong

IPC: H03G3/30

Abstract: Disclosed are systems and methods for automatic control of gain in audio and video conferencing applications to maintain a predetermined and stable audio level. In one embodiment, a first stage applies a first stage gain based on a long-term estimate of signal level, while a second stage gain, based on a short-term estimate of signal level assists the first stage gain to achieve a target level. Some embodiments of long-term level estimation utilize statistical analysis of a buffer to validate or arrive at a more accurate long-term signal level estimate.

公开(公告)号：WO2023014738A1

公开(公告)日：2023-02-09

申请号：PCT/US2022/039205

申请日：2022-08-02

Applicant: ZOOM VIDEO COMMUNICATIONS, INC.

Inventor： RAO, Yu

IPC: G10L21/0316 ,  H03G9/00 ,  H04M3/56 ,  H04R27/00 ,  G10L21/0216 ,  H03G7/002 ,  H03G7/007 ,  H03G9/005 ,  H04M3/18 ,  H04M3/568

Abstract: Disclosed are systems and methods for a frontend capture module of a video conferencing application, which can modify an input signal, received from a microphone device to match predetermined signal characteristics, such as voice signal level and expected noise floor. An Input stage, a suppression module and an output stage amplify the voice signal portion of the input signal and suppress the noise signal of input signal to predetermined ranges. The input stage selectively applies gains defined by a gain table, based on signal level of the input signal. The suppression module selectively applies a suppression gain to the input signal based on presence or absence of voice signal in the input signal. The output stage further amplifies the input signal in portions having a voice signal and applies a gain table to maintain a consistent noise floor.