The quantization is an adaptive non-uniform

scalar quantization.

A residual is calculated at each node as before, but is divided by the square root of the corresponding residual variance estimate prior to the scalar quantization operation.

R+1] symbols, TCQ requires only 4 multiplies, 2N + 4 adds, N compares, and 4 rate-(R - 1) scalar quantizations per data sample, where N is the number of states in the encoding trellis.

Then, for the proposed QF scheme, the complexity of the

scalar quantization is thus analyzed here.

Leonid, "Switched

scalar quantization with adaptation performed on both the power and the distribution of speech signal", Telfor Journal, vol.

Na, "Asymptotic formulas for variance-mismatched fixed-rate

scalar quantization of a Gaussian source", IEEE Trans.

Besides, after nonuniform

scalar quantization and being scrambled by the couple chaotic systems, the low frequency wavelet coefficients of 7 MSBs of the stego-image are converted into binary sequence as fragile watermark to be embedded into the stego-image by an improved LSB steganographic scheme.

This paper is organized as follows: A general analysis of non-uniform scalar quantization and A-law companding is given in Section 2.

One simple technique is switched codebook adaptive scalar quantization.

In this paper, we have presented and analyzed semilogarithmic A-law compounding characteristic for nonuniform scalar quantization of Gaussian source in a wide range of input signal's power.

Adaptive

scalar quantization without side information // IEEE Transactions on Image Processing, 1997.