| 摘要 |
FIELD: information technology. ^ SUBSTANCE: in one version, the device has an input module for receiving an audio signal and generating time-domain input values representing the audio signal; a transform module for transforming the input values into spectral coefficients using a modified discrete cosine transform (MDCT) which is recursively split into at least a discrete cosine transform type IV (DCT-IV), a discrete cosine transform type II (DCT-II), or both the DCT-IV and DCT-II, where each such transform is of smaller dimension than the MDCT, wherein at least some multiplication operations of the MDCT are merged with a prior windowing operation applied to the input values. ^ EFFECT: reduction in complexity of the device and less memory usage. ^ 35 cl, 15 dwg |
