ERROR CONCEALMENT OR CORRECTION OF SOUND SIGNAL, IMAGE SIGNAL AND VIDEO SIGNAL

摘要

PROBLEM TO BE SOLVED: To enable error concealment or error correction of, especially a signal transmitted from a radio channel or an ATM channel by forming discrete Fourier transformation of a block consisting of signal samples and forming the inverse discrete Fourier transformation of a Fourier coefficient of the block to form an redundancy increase signal. SOLUTION: A fast Fourier transformation(FFT) processor 1 receives a sampled sound signal x(k) as blocks of N samples and forms a Fourier coefficient X(k). An output signal of the processor 1 reaches an inverse FFT processor 3 from a distortion processor 2 and forms a signal x(i) undergoing filter processing. An output signal of the processor 3 is applied to a sound encoder 4 and a channel encoder 5 which prepares transmission and arranges signals in a transmission frame. A channel decoder receiving a transmission signal returns the frame structure of the signal to the original state and identifies a frame that is disturbed due to transmission or is not received.