Device and method for reducing quantization noise in a time-domain decoder

摘要

The present disclosure relates to a device and method for reducing quantization noise in a signal contained in a time-domain excitation decoded by a time-domain decoder. The decoded time-domain excitation is converted into a frequency-domain excitation. A weighting mask is produced for retrieving spectral information lost in the quantization noise. The frequency-domain excitation is modified to increase spectral dynamics by application of the weighting mask. The modified frequency-domain excitation is converted into a modified time-domain excitation. The method and device can be used for improving music content rendering of linear-prediction (LP) based codecs. Optionally, a synthesis of the decoded time-domain excitation may be classified into one of a first set of excitation categories and a second set of excitation categories, the second set including INACTIVE or UNVOICED categories, the first set including an OTHER category.

主权项

1. A device implemented in a CELP decoder for reducing quantization noise in a sound signal contained in a decoded CELP time-domain excitation to be processed through a LP synthesis filter to produce a synthesis thereof, the device comprising:
at least one processor; and a memory coupled to the processor and comprising non-transitory code instructions that when executed cause the processor to implement:
a converter of the decoded CELP time-domain excitation, before synthesis, into a frequency-domain excitation;a mask builder responsive to the frequency-domain excitation to produce a weighting mask for retrieving spectral information lost in the quantization noise;a modifier of the frequency-domain excitation to increase spectral dynamics by application of the weighting mask to the frequency-domain excitation; anda converter of the modified frequency-domain excitation into a modified CELP time-domain excitation containing a quantization noise-reduced version of the sound signal.