Pitch delay modification during frame erasures
AssigneeLucent Technologies Inc.
InventorYair Shoham
Life of this patent
Estimating the term…
Abstract
In a speech decoder which experiences frame erasure, the pitch delay associated with the first of consecutive erased frames is incremented. The incremented value is used as the pitch delay for the second of consecutive erased frames. Pitch delay associated with the first of consecutive erased frames may correspond to the last correctly received pitch delay information from a speech encoder (associated with a non-erased frame), or it may itself be the result of an increment added to a still previous value of pitch delay (associated with a still previous erased frame).
Claims5
A method for use in a speech decoder which falls to receive reliably at least a portion of each of first and second consecutive frames of compressed speech information, the speech decoder including a codebook memory for supplying a vector signal in response to a signal representing pitch-period information, the vector signal for use in generating a decoded speech signal, the method comprising:
- storing a signal having a value representing pitch-period information corresponding to said first frame;
- and
- incrementing said value of said signal for use in said second frame, such that said codebook memory supplies a vector signal in response to the incremented value of said signal.
A method for use in a speech decoder which fails to receive reliably at least a portion of a frame of compressed speech information for first and second consecutive frames, the speech decoder including an adaptive codebook memory for supplying codebook vector signals for use in generating a decoded speech signal in response to a signal representing pitch-period information, the method comprising:
- storing a signal having a value representing pitch-period information corresponding to said first frame;
- and
- if said stored value does not exceed a threshold, incrementing said value of said signal for use in said second frame.
Dependencies are inferred from the claim text.