Transform coding using adaptive bases and quantization
This paper considers the problem of universal transform coding based on estimating the Karhunen-Loeve transform from quantized data. The use of quantized data in the estimation allows the encoder and decoder to maintain the same state without any side information. A theorem is presented that proves, under certain conditions, that consistent estimation of all the required moments is possible from uniformly scalar quantized data regardless of the quantization coarseness. This consistent estimation requires the solution of nonlinear equations. Very simple approximations that avoid these nonlinear equations are used to develop a practical adaptive coding technique. Promising experimental results obtained with this method are presented.