[FFmpeg-user] Apparently the ffmpeg software scaler "sucks"

[Peter Rabbitson]

According to a test image taken from 
http://www.4p8.com/eric.brasseur/gamma.html ffmpeg's scaler does not 
properly deal with... well scaling.

The following pipeline produces a "SUCKS" verdict on ffmpeg 2.8.6:

   curl -s http://www.4p8.com/eric.brasseur/gamma-1.0-or-2.2.png \
| ffmpeg -f image2pipe -i - \
   -vf 'scale=w=iw/2:h=ih/2' -vframes 1 \
   -c:v bmp -f image2pipe - \
| ffplay -i -

Is this a real issue worthy of a bugreport, or is the test image/method 
flawed?

Thank you!