Multiplex communications – Packet communications
Reexamination Certificate
2003-03-21
2008-08-12
Matar, Ahmad F. (Department: 2614)
Multiplex communications
Packet communications
C370S465000, C370S352000, C370S230000, C704S207000, C704S218000, C704S214000
Reexamination Certificate
active
07411985
ABSTRACT:
A low complexity packet loss concealment method for use in voice-over-IP speech transmission calculates a cross-correlation of previous speech data to estimate the pitch period of the previous speech when speech frames have been lost. A tap interval used to calculate the cross-correlation is dynamically adapted, thereby reducing the computational complexity of the process. In addition, the pitch period estimation is bypassed completely when it is determined not to be necessary, as a result of the speech being unvoiced or silence. A waveform “bending” operation is performed into the current frame without inserting any algorithmic delay into each frame.
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Lee Minkyu
McGowan James William
Brown Kenneth M.
Le Karen
Lucent Technologies - Inc.
Matar Ahmad F.
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