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Implemented Model for Post-Masking

  As can be seen in figure 4, the post-masking effect varies with the length of the masker burst, from 5-10 ms up to 200 ms. This effect is exploited in the coder by a one-pole filter on the masking threshold over time:

equation213

The final output mask is then taken as tex2html_wrap_inline1050 . With this definition, a short burst does not affect tex2html_wrap_inline1052 much, while a longer burst will sustain the masking for a number of frames even though tex2html_wrap_inline1054 goes low again.



Bosse Lincoln
Sat Mar 7 16:27:43 PST 1998