Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
linjuming
Posts: 122 Joined: 2011-01-25T00:09:50-07:00
Authentication code: 8675308
Post
by linjuming » 2011-03-16T21:05:18-07:00
how to create a completely transparent png?
convert -size 200x100
xc:transparent img/selected_overlay/selected_overlay.png (black color)
convert -size 200x100
xc:none img/selected_overlay/selected_overlay.png (black color)
convert -size 200x100 img/selected_overlay/selected_overlay.png (error)
anthony
Posts: 8883 Joined: 2004-05-31T19:27:03-07:00
Authentication code: 8675308
Location: Brisbane, Australia
Post
by anthony » 2011-03-16T21:17:15-07:00
there was a few versions that had problems in PNG output due to re-development work.
Upgrade to the very latest.
fmw42
Posts: 25562 Joined: 2007-07-02T17:14:51-07:00
Authentication code: 1152
Location: Sunnyvale, California, USA
Post
by fmw42 » 2011-03-16T21:26:56-07:00
this works just fine on IM 6.6.8.4 Q16 Mac OSX Tiger
convert -size 200x100 xc:none tmp.png
linjuming
Posts: 122 Joined: 2011-01-25T00:09:50-07:00
Authentication code: 8675308
Post
by linjuming » 2011-03-16T21:34:03-07:00
thank you , so I will update the vesion ,hope i will help.
fmw42
Posts: 25562 Joined: 2007-07-02T17:14:51-07:00
Authentication code: 1152
Location: Sunnyvale, California, USA
Post
by fmw42 » 2011-03-16T21:40:06-07:00
try on your current version
convert -size 200x100 xc:"rgba(0,0,0,0)" PNG32:tmp.png
or
convert -size 200x100 xc:"rgba(0,0,0,0)" -type truecolormatte PNG32:tmp.png
see if that helps before upgrading.
linjuming
Posts: 122 Joined: 2011-01-25T00:09:50-07:00
Authentication code: 8675308
Post
by linjuming » 2011-03-16T21:46:15-07:00
yes , it works
using "png32: " helps