Is this expected behavior for -coalesce IM 6.7.9.0 Q16

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fmw42
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Is this expected behavior for -coalesce IM 6.7.9.0 Q16

Post by fmw42 »

IM 6.7.9.0 Q16 Snow Leopard

Is this expected behavior for -coalesce? Without -coalesce I get a meaningful result. With coalesce the result it totally transparent.

Image
Image
Image


convert -size 128x128 xc: logo3.jpg lena2.jpg zelda3.jpg miff:- |\
convert - -delete 0 -evaluate-sequence mean show:

convert -size 128x128 xc: logo3.jpg lena2.jpg zelda3.jpg miff:- |\
convert - -coalesce -delete 0 -evaluate-sequence mean show:
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magick
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Re: Is this expected behavior for -coalesce IM 6.7.9.0 Q16

Post by magick »

We'll take a look @ the problem. In the mean-time add -alpha off to your command line.
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fmw42
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Re: Is this expected behavior for -coalesce IM 6.7.9.0 Q16

Post by fmw42 »

magick wrote:We'll take a look @ the problem. In the mean-time add -alpha off to your command line.

Thanks. I just removed the -coalesce in my script and it works fine. But I wanted to be sure that this is what you expect when using -coalesce.
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anthony
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Re: Is this expected behavior for -coalesce IM 6.7.9.0 Q16

Post by anthony »

As you have not set disposals, and all later frames are opaque -coalesce should do nothing. I'd say something is haywire in the low level comparison functions due to alpha changes.

I have no time to look at it though.
Anthony Thyssen -- Webmaster for ImageMagick Example Pages
https://imagemagick.org/Usage/
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fmw42
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Re: Is this expected behavior for -coalesce IM 6.7.9.0 Q16

Post by fmw42 »

anthony wrote:As you have not set disposals, and all later frames are opaque -coalesce should do nothing. I'd say something is haywire in the low level comparison functions due to alpha changes.

I have no time to look at it though.
I believe Magick made a change already.


2012-08-16 6.7.9-1 Cristy <quetzlzacatenango@image...>
...
Don't add matte channel for -coalesce if input images don't have one.
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