Packet loss concealment for overlapped transform codecs

A computer-readable medium having computer executable instructions for, concealing missing frames of coefficients of an overlapped transform of a signal by reconstructing blocks of samples of the signal corresponding to the missing frames of coefficients, said computer executable instructions comprising:

• determining which frames are missing from a set of received frames of the overlapped transform of the signal;
• locating an under-determined block of samples of the signal corresponding to a missing frame;
• extracting coefficients from at least one received frame;
• constructing from the extracted coefficients a set of linear equations representing partial constraints on the under-determined block of samples;
• modeling samples of the signal neighboring the under-determined block of samples;
• constructing from the modeled samples a basis for the under-determined block of samples;
• optimizing the coefficients of the under-determined block of samples with respect to the constructed basis and the partial constraints;
• and
• reconstructing a block of samples corresponding to the missing frame from the optimized coefficients with respect to the basis.

A method for reconstructing one or more missing data frames of an overlapped transform coded signal by reconstructing one or more of the missing data frames, comprising:

• storing received data frames of the coded signal to a signal buffer;
• determining whether any data frames are of the data frames are missing;
• constructing a set of under-determined linear equations from partial information extracted from at least one of a preceding neighboring frame and a succeeding neighboring frame, relative to a missing frame;
• modeling the at least one neighboring frame and using the at least one modeled neighboring frame for generating a basis for the missing frame;
• identifying an optimal solution to the set of under-determined linear equations as a function of the generated basis;
• reconstructing the missing frame from the identified optimal solution;
• and
• inserting the reconstructed missing frame into its proper position between corresponding neighboring frames in the signal buffer.