| 摘要 |
The invention relates to HFR (High-Frequency Reconstruction/Regeneration) of audio signals. In particular, the invention relates to a method and system for performing HFR of audio signals having large variations in energy level within the low-frequency range which is used for modification of high frequencies of the audio signal. A system is configured to generate a plurality of high-frequency subband signals covering a high frequency interval from a plurality of low-frequency subband signals. The system comprises facilities for receiving the plurality of low-frequency subband signals; facilities for receiving a set of target energies, each target energy covering a different target interval within the high-frequency interval and being indicative of the required energy of one or more high-frequency subband signals lying within the target interval; facilities for generating the plurality of high-frequency subband signals from the plurality of low-frequency subband signals and from a plurality of spectral gain factors associated with the plurality of low-frequency subband signals, respectively; and facilities for adjusting the energy of the plurality of high-frequency subband signals using the set of target energies. |
