Method and apparatus for controlling audio frame loss concealment

An apparatus for creating a substitution frame for a lost audio frame, the apparatus comprising:

• at least one processor;
• at least one memory storing a computer program code that is executed by the processor to perform operations comprising:
• generating a prototype frame from a segment of a previously received or reconstructed audio signal;
• transforming the prototype frame into a frequency domain;
• analyzing a previously reconstructed signal frame and frame loss statistics to detect predetermined conditions that could lead to suboptimal signal reconstruction quality if a first concealment method is applied;
• applying the first concealment method responsive to when said predetermined conditions are not detected, wherein the first concealment method comprises:
• applying a sinusoidal model to the prototype frame to identify a frequency of a sinusoidal component of the audio signal, calculating a phase shift θk for the sinusoidal component and phase shifting the sinusoidal component by θk;
• applying a second concealment method, responsive to when at least one of said predetermined conditions is detected, wherein the second concealment method comprises:
• adapting the first concealment method by selectively adjusting a magnitude of the prototype frame spectrum;
• and
• creating the substitution frame by performing an inverse frequency transform of a frequency spectrum of the prototype frame.

A computer program product comprising a non-transitory computer readable medium storing computer program code which when executed by at least one processor causes the at least one processor to:

• generate a prototype frame from a segment of a previously received or reconstructed audio signal;
• transform the prototype frame into a frequency domain;
• analyze a previously reconstructed signal frame and frame loss statistics to detect predetermined conditions that could lead to suboptimal signal reconstruction quality if a first concealment method is applied;
• apply the first concealment method responsive to when said conditions are not detected, wherein the first concealment method comprises:
• applying a sinusoidal model to the prototype frame to identify a frequency of a sinusoidal component of the audio signal, calculating a phase shift θk for the sinusoidal component and phase shifting the sinusoidal component by θk;
• apply a second concealment method, responsive to when at least one of said conditions is detected, wherein the second concealment method comprises:
• adapting the first concealment method by selectively adjusting a magnitude of the prototype frame spectrum;
• and
• create the substitution frame by performing an inverse frequency transform of a frequency spectrum of the prototype frame.