UPMIX METHOD AND APPARATUS FOR CONVERTING STEREO CHANNEL INPUT SIGNAL TO MULTI-CHANNEL OUTPUT SIGNAL

摘要

PURPOSE: An up-mixing method for converting a stereo channel input signal into a multichannel output signal and an apparatus thereof are provided to apply a sound source separation technique in a stereo signal itself, thereby maintaining spatial properties including sound sources during a mixing process of a multichannel signal. CONSTITUTION: An up-mixing apparatus divides an input signal of a stereo channel into a plurality of sub-bands in a frequency range(S210). The sub-band with a highest mutual correlation is selected as a representative sub-band by measuring a mutual correlation between two channels of a stereo input signal(S220). A sound source level difference value between estimated two channels is determined as a first sound image fixing level difference value by analyzing the stereo input signal(S230). A sound image fixed sound source signal and reverberation signal are separated(S240). A sound image fixing level difference value is calculated with respect to a front channel of a multichannel speaker output system(S250). The up-mixing apparatus synthesizes the separated sound image fixed sound source signal and reverberation signal into a multichannel output signal(S260).