Re: [Gimp-developer] Tuning and choosing resampling methods in GEGL/GIMP

[Nicolas Robidoux <nicolas robidoux gmail com>]

Let r be the downsampling ratio (approximately equal to the output and
input widths in pixels).

I would not expect NoHalo to give great results if r * OFFSET_0 is much
smaller than 1, and LoHalo if r * OFFSET_0 is much smaller than 2.

Specifically, if OFFSET_0 is 16, I would not expect any of the two methods
to give great results if downsizing to 1% original size (r * 16 = .16 which
is much smaller than 1). Tolerable results? Maybe. Great? Probably not.

This limitation used to be overcome by relying on mipmaps. For speed +
stability reasons, they've been taken out. (I do wonder if using one mipmap
level could make enough of a difference.)

Short version: Big time downsampling most likely will not be as good as it
used to be.