Audio encoder, audio decoder and related methods for enhancing transient processing, computer program

An audio post-processor (100) for post-processing an audio signal (102) having a time-varying high-frequency gain information (104) as secondary information comprises: a band extractor (110) for extracting a high-frequency band (112) from the audio signal (102) and a low-frequency band (114) from the audio signal (102); a high-band processor (120) for performing a time-varying modification of the high-frequency band (112) according to the time-varying high-frequency gain information (104) to obtain a processed high-frequency band (122); and a combiner (130) for combining the processed high-frequency band (122) and the low-frequency band (114). In addition, a preprocessor is illustrated. (Automatic translation with Google Translate, no legal value)