1. Apparatus for processing an audio signal to acquire control information for a speech enhancement filter, comprising: a feature extractor for acquiring a time sequence of short-time spectral representations of the audio signal and for extracting at least one feature in each frequency band of a plurality of frequency bands for a plurality of short-time spectral representations, the at least one feature representing a spectral shape of a short-time spectral representation in a frequency band of the plurality of frequency bands; and a feature combiner for combining the at least one feature for each frequency band using combination parameters to acquire the control information for the speech enhancement filter for a time portion of the audio signal.