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Old 16th March 2013, 03:37   #4  |  Link
akupenguin
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Join Date: Sep 2004
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Quote:
Originally Posted by benwaggoner
Heck, an optimal scaling algorithm has as many taps as the source frame has pixels that overlap with the region that the output pixel comes from, so that'd be 25+ even in the 1080p -> 192p case.
Are there any scaling algorithms that don't do that? Other than nearest neighbor.

Quote:
Originally Posted by xooyoozoo
multiple steps of 0.5 reductions each time using gaussian and bilinear
Why would you do that, rather than composing all of those steps into a single FIR filter? Same ideal result, less intermediate rounding, less cache thrashing.
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