Patent ID: 8214200
Filing Date: 2012-07-03
Classification: G06F,G10L

Abstract:
1. a method for generating an audio sine wave directly in the transform domain by approximating an MDCT coefficient of a block of a sinusoidal sequence having a defined frequency, the block being multiplied by a window sequence and having a block length and a block index, said method comprising: defining a finite trigonometric series to approximate the window sequence, pre-computing a window summation table using said finite trigonometric series and the defined frequency, said window summation table having a row corresponding to the MDCT coefficient, computing a block phase with the defined frequency of the sinusoidal sequence, the block length and the block index, computing a phase vector corresponding to the MDCT coefficient using said block phase, approximating the value of the MDCT coefficient by computing a dot product of said row of said window summation table with said phase vector, and performing the above steps using a processor to generate said audio sine wave.