Is it shadow bug?

[excel]

This code works on two servers with different ImageMagick versions.

Code: Select all

exec("convert -size 200x200 xc:transparent -fill 'rgba(255, 87, 34, 0.5)' -draw 'circle 95,95 30,35'  \( +clone -background black -shadow 70x3+1+1 \) +swap -background none -layers merge +repage result.png");

Both servers based in Debian operating system.

First server:
ImageMagick 6.9.2-7 Q16 x86_64 2015-12-03

Second server:
ImageMagick 6.8.9-9 Q16 x86_64 2015-01-05

Why the different results?

From first server:



From second server:

[fmw42]

I can confirm the difference using IM 6.9.2.10 Q16 and 6.8.9.9 Q16 Mac OSX Snow Leopard. I know there was some partial transparency blending changes not too long ago, but do not know if this is related. The change seems to have occurred between 6.9.1.6 and 6.9.1.7.

[magick]

It appears to be a transient problem which fixed in recent releases of ImageMagick. The current release, ImageMagick 6.9.2-10, returns similar results to your first image, res1.png. The normalized RMSE metric for 6.9.2-10 vs 6.9.2-7 is 5.8503e-06, whereas for 6.8.9-9 vs 6.9.2-7, we get an RMSE of 0.0323784.