Legacy ImageMagick Discussions Archive

Preliminary testing suggests that the Quadratic filter (2nd degree B-spline with support [-1.5,1.5]) works well with EWA (when upsampling; downsampling, of course, is always another story): Of course, it's blurry and halo free.

It is also essentially a fit of the Gaussian filter That explains why it has low aliasing effects, at the cost of blurry effects.

... or pushing the luma and chroma channels through EWA with BC-splines with different c: closer to Cubic for the chroma than for the luma, esp. when using chroma subsampling.