Page 1 of 1

possible -alpha Shape bug

Posted: 2017-05-03T19:40:15-07:00
by jwebst
I believe I may have the same issue that was reported as solved in a previous post https://www.imagemagick.org/discourse-s ... pe#p139313.

Input:
Image

Code: Select all

convert alpha_extract.png -background blue -alpha Shape alpha_shape.tiff
convert alpha_extract.png -background blue -alpha Shape alpha_shape.png
Both of these commands result in solid blue fields on ImageMagick 7.0.5-4 Q16 and ImageMagick 7.0.5-5 Q16 for OSX

Re: possible -alpha Shape bug

Posted: 2017-05-03T19:55:14-07:00
by fmw42
These commands work fine for IM 6.9.8.4 Q16

Code: Select all

convert moon.png -background red -alpha shape moon_red.miff

Code: Select all

convert moon.png -background red -alpha shape moon_red.mpc

Code: Select all

convert moon.png -background red -alpha shape moon_red.png

However, they produce a solid red image for IM 7.9.8.5 Q16 Mac OSX Sierra

Code: Select all

magick moon.png -background red -alpha shape moon_red.miff

Code: Select all

magick moon.png -background red -alpha shape moon_red.mpc

Code: Select all

magick moon.png -background red -alpha shape moon_red.png
So there is a bug in IM 7.0.5.5

Re: possible -alpha Shape bug

Posted: 2017-05-06T12:45:19-07:00
by magick
Thanks for the problem report. We can reproduce it and will have a patch to fix it in GIT master branch @ https://github.com/ImageMagick/ImageMagick later today. The patch will be available in the beta releases of ImageMagick @ http://www.imagemagick.org/download/beta/ by sometime tomorrow.

Re: possible -alpha Shape bug

Posted: 2017-05-08T12:23:50-07:00
by fmw42
I am still getting a solid red image for the PNG command in the latest beta as of today. The MPC and MIFF work fine.

Code: Select all

im7beta magick moon.png -background red -alpha shape moon_red.png

Re: possible -alpha Shape bug

Posted: 2017-05-08T17:03:13-07:00
by magick
Thanks for the problem report. We can reproduce it and will have a patch to fix it in GIT master branch @ https://github.com/ImageMagick/ImageMagick later today. The patch will be available in the beta releases of ImageMagick @ http://www.imagemagick.org/download/beta/ by sometime tomorrow.

Re: possible -alpha Shape bug

Posted: 2017-05-10T09:52:54-07:00
by fmw42
Thanks. It seems to be fixed for the PNG result in today's beta