Variable Frame Rate Parameter Encoding Via Adaptive Frame Selection Using Dynamic Programming

This paper presents a block-coded VFR strategy that removes the familiar "anchor frame" constraint in favor of a generalized delayed decision analysis. This approach is referred to as adaptive frame selection using dynamic programming (AFS/DP). The AFS/DP algorithm determines optimal breakpoint locations using a perceptually-based performance measure, accommodates fixed bit-rate operation, and operates with fixed delay and low complexity. The AFS/DP algorithm has been implemented in the context of the MELP vocoder at 2400 bits/sec, and has demonstrated comparable performance to block VFR methods, with lower coder delay.