×

Low-Complexity Packet Loss Concealment for Transcoded Audio Signals

  • US 20190311723A1
  • Filed: 04/09/2019
  • Published: 10/10/2019
  • Est. Priority Date: 04/09/2018
  • Status: Active Grant
First Claim
Patent Images

1. A method for concealing packet loss in a received audio stream, the method comprising:

  • receiving, by an audio communication system comprising one or more servers, packets of an audio stream, the received audio stream being in a non-lapped transform domain format, the packets having a sequential order, where a block of packets is missing in the sequence, the block of packets including at least one packet, each packet of the audio stream having a received window size;

    decoding, by the audio communication system, the received packets to a sequence of blocks of a raw audio signal;

    replacing, by the audio communication system, each missing packet in the sequence with a reduced-energy signal block, whereby the sequence of blocks of the raw audio signal comprises at least one reduced-energy signal block, wherein the reduced-energy signal block has a lower energy in comparison to remaining blocks of the raw audio signal, such that the reduced-energy signal block is distinguishable from remaining blocks of the received raw audio signal;

    modifying, by the audio communication system, each reduced-energy signal block of the raw audio signal at one of a beginning boundary and an ending boundary;

    shifting, by the audio communication system, the raw audio signal by a predetermined delay such that a start and end of each reduced energy block of the raw audio signal does not coincide with a peak of a transform window of a lapped transform domain format;

    encoding, by the server, the raw audio signal into transform windows having the lapped transform domain format, wherein packet loss concealment is performed for a selected transform window of the encoded audio signal, the selected transform window having a modified reduced energy signal block located at a center portion; and

    transmitting, by the audio communication system, the encoded audio signal to an endpoint.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×