FINITE-PRECISION ANALYSIS OF THE PIPELINED ADPCM CODER

Roundoff error analysis of a pipelined adaptive differential pulse cod e modulation (ADPCM) coder is presented. The pipelined coder has been developed by employing the relaxed look-ahead technique. It is shown t hat the precision of the quantized prediction error and those of the p redictor coefficients are critical and analytical expressions for lowe r bounds on these precisions are derived. In addition, an expression f or the excess mean-squared prediction error due to finite-precision is also derived. Based on these expressions, a systematic method for ass igning precision to various signals in the coder is developed. Simulat ion results with real image data confirm the results of this analysis.