CONF . ON IMAGE PROCESSING 1 Digital Halftoning as 2 - D Delta - Sigma Modulation
نویسندگان
چکیده
|The error di usion algorithm for digital halftoning is equivalent in form to a noise-shaping feedback coder, a class of delta-sigma modulator. The white noise assumption of the quantizer error is known to be false; in fact, the quantizer error is seen to be highly correlated with the input image. To account for this correlation, we use a gain model for the quantizer. This model accurately predicts the edge sharpening and noise shaping caused by all error di usion schemes. It also permits an extension of error di usion to oversampled imagery.
منابع مشابه
Digital Halftoning as 2-D Delta-Sigma Modulation
|The error di usion algorithm for digital halftoning is equivalent in form to a noise-shaping feedback coder, a class of delta-sigma modulator. The white noise assumption of the quantizer error is known to be false; in fact, the quantizer error is seen to be highly correlated with the input image. To account for this correlation, we use a gain model for the quantizer. This model accurately pred...
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