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+
+artifact types:
+---------------------------------------------------------------------
+ringing
+ wave or noise like patterns around sharp edges
+ bad: sinc, lanczos (with high filter length)
+ acceptable: lanczos (with low filter length), cubic, spline
+ ok: area, (fast)blinear, gauss, point
+
+blur
+ loss of detail / high frequency
+ bad: gauss with high variance
+ acceptable: (fast)bilinear, area
+ ok: others
+
+aliasing (only downscale)
+ straight lines look like staircases
+ areas of high detail look worse
+ regular patterns turn into a funny looking mess (moire patterns)
+ bad: fast bilinear, point, gauss with low variance
+ acceptable: area
+ ok: others
+
+blocky (upscale only)
+ looks like the image is made of rectangular blocks like a mosaic
+ bad: point
+ ok: others
+
+recommendations: (based upon my personal opinion many ppl might disagree ...)
+---------------------------------------------------------------------
+
+the recommended scalers for upscaling:
+fast_bilinear, point if speed is important
+cubic, spline, lanczos if quality is important
+
+the recommended scalers for downscaling:
+fast_bilinear, point if speed is important
+gauss, bilinear if quality is important
+cubic, spline, lanczos if a sharper picture is important
+
+note: when encoding at a limited amount of bits (not constant quantizer)
+then a slightly blurred input might look better after decoding than a slightly
+sharpened one, especially for lower bitrates
+
+sws numbers / names / artifact types
+-------------------------------------------------------------------------
+r ringing
+b blurry
+a aliasing (downscale only)
+m mosaic (blocky) (upscale only)
+
+-sws 0 fast bilinear bA
+-sws 1 bilinear b
+-sws 2 bicubic high sharpness r
+ low sharpness b
+-sws 3 experimental ????
+-sws 4 nearest neighbour AM
+-sws 5 area ba
+-sws 6 luma bicubic / chroma bilinear r
+-sws 7 gauss low sharpness B
+ high sharpness AM
+-sws 8 sinc R
+-sws 9 lanczos long filter R
+ short filter b
+-sws 10 bicubic spline r
+
+Notes:
+ area upscale is identical to bilinear