Sufficient conditions are presented for uniqueness of a locally optimal quantizer being a stationary point of the quantization distortion measure
![E[f(x,\\eta)]](/images/tex/5582.gif)
, the expected value of an error weighting function

, where

is a random variable to be quantized, where the probability density function

describing

is continuous and positive on some finite or infinite interval and zero outside it, and where

is the quantization error. The function

is assumed convex and symmetric in

and zero only for

. It is shown that in the cases of

and

, the simple condition of concavity of In

is sufficient for uniqueness of a locally optimal quantizer.