Low-Rate Signal Compression Incorporating Decimation

The paper presents results for PCM- and DPCM-like signal compression schemes that incorporate lowpass -filtering and downsampling prior to the actual encoder, and corresponding upsampling and filtering to reconstruct the signal to the original rate after the decoder. This scheme is suggested by rate-distortion theory for coding signals with monotonically decaying spectra at low rate. The cutoff frequencies are optimized for best performance