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Cannot apply watermark to GIF

Posted: 2012-01-08T13:46:31-07:00
by smantscheff
I'm trying to add a watermark stamp to a gif image. I have a script which works fine for JPGs:

Code: Select all

composite -gravity south -geometry +0+10 stamp.png  %1 %2
But when applied to GIF files they result in a grey only bitmap. I tried to convert stamp.png to stamp.gif first, but to no avail.

Input looks like that:
Image:
Image
Stamp:
Image

IM runtime is ImageMagick 6.7.1-0 2011-07-06 Q16 (Windows 7) and ImageMagick 6.5.7-8 2010-12-02 Q16 (Ubuntu). Result is the same on both: Image

How can I apply this watermark to the image?

Re: Cannot apply watermark to GIF

Posted: 2012-01-08T13:54:05-07:00
by fmw42
jpg does not support transparency. you would likely need to flatten your transparent image with some background color first. Or save your output as png or gif or tif

Re: Cannot apply watermark to GIF

Posted: 2012-01-08T14:30:33-07:00
by smantscheff
Or save your output as png or gif or tif.
This is what I am trying. Input is GIF and PNG, output is GIF. But the merging of the two yields bad results.

Re: Cannot apply watermark to GIF

Posted: 2012-01-08T15:06:02-07:00
by fmw42
try this, it works for me. note your large image has two frames and a virtual canvas. use +repage to remove the virtual canvas and use just the first frame.

convert zahnarzt1.gif[0] stamp.png +repage -gravity south -geometry +0+10 -compose over -composite result.gif

Re: Cannot apply watermark to GIF

Posted: 2012-01-08T19:21:03-07:00
by anthony
Also see Animation Modifications
http://www.imagemagick.org/Usage/anim_mods/#annotating
And Image Annotation, Watermarking
http://www.imagemagick.org/Usage/annota ... termarking

Fred however is right you have two frames with slight differences in 'dithering', Especially in E-Dither 'speckle' on the Ken Doll's pants. But no real animated differences between the two frames.

For more help more detail of what you want to achieve is needed.

Re: Cannot apply watermark to GIF

Posted: 2012-01-09T01:53:09-07:00
by smantscheff
Thanks for your help, it worked.
Someday I will be grown up and understand all this - or at least some of it.