Phase reconstruction in a speech decoder

In a computer system that implements a speech decoder, a method comprising:

• receiving encoded data as part of a bitstream;
• decoding the encoded data to reconstruct speech, including:
• decoding residual values, including:
• decoding a sparseness value and correlation values;
• decoding one or more sets of magnitude values;
• decoding a set of phase values;
• and
• reconstructing the residual values, including:
• reconstructing complex amplitude values for one or more subframes of a current frame using the one or more sets of magnitude values and the set of phase values;
• applying an inverse frequency transform to the complex amplitude values for the respective subframes;
• and
• selectively adding noise to the residual values based at least in part on the correlation values and the sparseness value;
• and
• filtering the residual values according to linear prediction coefficients;
• and
• storing the reconstructed speech for output.

One or more computer-readable memory or storage devices having stored thereon encoded data as part of a bitstream, the encoded data including a set of coefficients, an offset value, and a slope value for a set of phase values, the encoded data being organized to facilitate decoding of the encoded data to reconstruct speech, with a speech decoder implemented using one or more processors, by operations comprising:

• decoding residual values, including:
• decoding the set of phase values using the set of coefficients, the offset value, and the slope value, including reconstructing at least some of the set of phase values using a weighted sum of basis functions;
• and
• reconstructing the residual values based at least in part on the set of phase values;
• and
• filtering the residual values according to linear prediction coefficients.