Least squares quantization in PCM

  title={Least squares quantization in PCM},
  author={Stuart P. Lloyd},
  journal={IEEE Trans. Inf. Theory},
  • S. P. Lloyd
  • Published 1 March 1982
  • Computer Science
  • IEEE Trans. Inf. Theory
It has long been realized that in pulse-code modulation (PCM), with a given ensemble of signals to handle, the quantum values should be spaced more closely in the voltage regions where the signal amplitude is more likely to fall. It has been shown by Panter and Dite that, in the limit as the number of quanta becomes infinite, the asymptotic fractional density of quanta per unit voltage should vary as the one-third power of the probability density per unit voltage of signal amplitudes. In this… 

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