Encoding device and method, decoding device and method, and program

摘要

The present technology relates to an encoding device and method, a decoding device and method, and a program that enable audio of a high audio quality to be obtained with a smaller code amount.;The encoding device multiplexes low frequency encoding data obtained by encoding a low frequency component of an input signal and high frequency encoding data obtained by encoding data including an estimation coefficient to acquire a high frequency component of the input signal by estimation and outputs multiplexed data. When the input signal is encoded, a calculation unit calculates pseudo high frequency subband power to be an estimation value of power of the high frequency component from an estimation coefficient selected in a frame immediately before a frame of a processing target and the high frequency component of the input signal. In addition, a determination unit determines whether reuse of the estimation coefficient of the immediately previous frame is enabled in the frame of the processing target, on the basis of a comparison result of the calculated pseudo high frequency subband power and actual high frequency component power. The present invention can be applied to the encoding device.

主权项

1. An encoding device including:
a subband division unit that performs band division of an input signal and generates high frequency subband signals of subbands of a high frequency side of the input signal; a calculation unit that calculates pseudo high frequency subband power to be an estimation value of high frequency subband power of the high frequency subband signal of a frame of a processing target, on the basis of a feature amount obtained from a low frequency signal of the input signal and an estimation coefficient selected in a frame immediately before the frame of the processing target of the input signal among a plurality of estimation coefficients prepared in advance; a generation unit that, when reuse of the estimation coefficient of the immediately previous frame is enabled in the frame of the processing target, on the basis of the pseudo high frequency subband power and the high frequency subband power obtained from the high frequency subband signal, generates data to obtain the reuse enabled estimation coefficient; a low frequency encoding unit that encodes the low frequency signal and generates low frequency encoding data; and a multiplexing unit that multiplexes the data and the low frequency encoding data and generates an output code string.