This paper addresses progressive wavelet image coding within the trellis-coded space-frequency quantization (TCSFQ) framework [1]. A method similar to that in [2] is used to approximately invert TCSFQ when decoding at rates lower than the encoding rate. Our experiments show that the loss incurred for progressive transmission is within 1 dB in peak signal-to-noise ratio and that the progressive ...

In quantisation of any source with a nonuniform probability density function, the entropy coding of the quantizer output can result in a substantial decrease in bit rate. A straight-forward entropy coding scheme presents us with the problem of the variable data rate. A solution in a space of dimensionality N is to select a subset of elements in the N-fold cartesian product of a scalar quantiaer...

Motivated by the recent work of Laroia and Farvardin, this paper presents new reducedcomplexity methods for avoiding the bu ering problems associated with entropy-coded, scalar quantization. Basically, given a xed-size source block, these methods use dynamic programming and other techniques to search the sequences produceable by an entropycoded, scalar quantizer for one with minimum distortion ...

Trellis Coded Modulation [5] combines the Viterbi Algorithm [4] with PSK or QAM signalling to achieve a coding gain, using signal set expansion as an alternative to bandwidth expansion. Optimum detection of TCM requires the calculation of Euclidean distances in the signal set space. Circular Quantization of received signal vectors as an alternative to Euclidean distance calculation has been sho...

A visually-optimal quantization and rate-control strategy based on results of recent contrast sensitivity and suprathreshold summation experiments is proposed. At suprathreshold contrasts, masked detection thresholds for wavelet subband quantization distortions were approximately equal for scale-3, 4, and 5 distortions; approximately 52% greater for scale-2 distortions; and approximately 84% gr...

In this paper, we propose a practical approach to minimizing embedding impact in steganography based on syndrome coding and trellis-coded quantization and contrast its performance with bounds derived from appropriate rate-distortion bounds. We assume that each cover element can be assigned a positive scalar expressing the impact of making an embedding change at that element (single-letter disto...

In this paper, we evaluate the choice of suitable quantization characteristics for both the decoder messages and the received samples in Low Density Parity Check (LDPC) coded systems using M-QAM (Quadrature Amplitude Modulation) schemes. The analysis involves the demapper block that provides initial likelihood values for the decoder, by relating its quantization strategy of the decoder. A mappi...

| This paper describes two new xed-rate entropy-coded quantization methods for stationary memoryless sources where the structure of code-words are derived from a variable-length scalar quantizer. In the rst method, we formulate the quantization as a zero-one integer optimization problem. We show that the resulting integer program can be closely approximated by solving a simple linear program. T...

A combined source/channel coding scheme without explicit error protection is proposed to transmit images through binary noisy channels. Unlike the error protection with re-transmission scheme and error concealment scheme by inserting synchronization codewords to entropy-coded bitstream, the proposed coding scheme employs transform coding, "xed-rate uniform threshold trellis coded quantization (...

We propose a new vector quantization approach, which consists of Hidden Markov Models(HMMs) and entropy coding scheme. The entropy coding system is determined depending on the speech status modeled by HMMs, so the proposing approach can adaptively allocate suitable numbers of bits to the codewords. This approach realizes about 0.3[dB] coding gain in cepstrum distance(8 states HMMs). In other wo...