Patent ID: 9626976
Date: 2017-04-18
CPC Classifications: G10L,H04S

Claim:
1. A decoding method of decoding a signal, the decoding method comprising: receiving, by a decoding apparatus, a bitstream including a down mix signal, residual information and spatial information for expanding a down-mix signal to multi-channel signal, wherein the spatial information includes down-mix identification information indicating that the down-mix signal is 3D encoded and size information indicating a size in bits of the residual information; skipping, by the decoding apparatus, the residual information based on the size information; determining, by the decoding apparatus, based on the down-mix identification information, whether the down-mix signal is a first 3D down-mix signal obtained by performing a 3D rendering operation; correcting, by the decoding apparatus, the spatial information by replacing at least one of first spatial information corresponding to a first parameter band and second spatial information corresponding to a second parameter band with an average of the first spatial information and the second spatial information, the first parameter band being adjacent to the second parameter band; and generating by the decoding apparatus, an output signal using the downmix signal, the down-mix identification information and the corrected spatial information, wherein if the down-mix identification information indicates that the down mix signal is the first 3D down-mix signal obtained by performing a 3D rendering operation, the generating the output signal comprises: removing, by the decoding apparatus, 3D effects from the first 3D down-mix signal by performing a 3D rendering operation on the first 3D down-mix signal using a head related transfer function (HRTF), the 3D rendering operation being performed using an inverse filter of a filter used for generating the first 3D down-mix signal; and generating by the decoding apparatus, a multi-channel signal using a down-mix signal obtained by the removal and the spatial information, wherein the first 3D down-mix signal is a stereo down-mix signal with 3D effects which is reproduced as imaginary multi-channel signal, wherein if the down-mix identification information indicates that the down mix signal is not the first 3D down-mix signal, the generating the output signal comprises: generating a second 3D down-mix signal by performing the 3D rendering operation using the head related transfer function (HRTF).