Communications Toolbox

dpcmopt

Optimize differential pulse code modulation parameters

Syntax

• predictor = dpcmopt(training_set,ord);
  [predictor,codebook,partition] = dpcmopt(training_set,ord,len);
  [predictor,codebook,partition] = ...
     dpcmopt(training_set,ord,initcodebook);
  

Description

predictor = dpcmopt(training_set,ord) returns a vector representing a predictive transfer function of order ord that is appropriate for the training data in the vector training_set. predictor is a row vector of length ord+1. See Representing Quantization Parameters for more about its format.

Note    dpcmopt optimizes for the data in training_set. For best results, training_set should be similar to the data that you plan to quantize.

[predictor,codebook,partition] = dpcmopt(training_set,ord,len) is the same as the syntax above, except that it also returns corresponding optimized codebook and partition vectors codebook and partition. len is an integer that prescribes the length of codebook. partition is a vector of length len-1. See either Representing Quantization Parameters or the reference page for quantiz in this chapter, for a description of the formats of partition and codebook.

[predictor,codebook,partition] = dpcmopt(training_set,ord,initcodebook) is the same as the first syntax, except that it also returns corresponding optimized codebook and partition vectors codebook and partition. initcodebook, a vector of length at least 2, is the initial guess of the codebook values. The output codebook is a vector of the same length as initcodebook. The output partition is a vector whose length is one less than the length of codebook.

Examples

See Example: Comparing Optimized and Nonoptimized DPCM Parameters for an example that uses dpcmopt.

See Also
dpcmenco, dpcmdeco, quantiz, lloyds

dpcmenco

encode