convert output changes with recent update

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jamtat
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convert output changes with recent update

Post by jamtat » 2019-05-31T12:47:09-07:00

A recent ImageMagick update (to version 7.0.8-47) on my system has resulted in production of errant results from a script I've been running for a few months now. The script overlays onto an image some text that I download from the internet at regular intervals, adding a blurred shadow effect to the text and positioning it on an image. For reference, the script is as follows:

Code: Select all

convert -size 240x180 xc:none -gravity center -stroke black -strokewidth 2 -pointsize 36 -annotate 0 \
"$(cat /home/user/weather/currnt-cond.txt)" -background none -shadow 100x3+0+0 +repage -stroke none \
-fill lightblue -annotate 0 "$(cat /home/user/weather/currnt-cond.txt)" /home/user/weather/wmap-hi_res.gif \
+swap -gravity northeast -geometry +0-3 -composite /home/user/weather/wmap-hi_res-NE.gif
Whereas previous to the upgrade this would add a gently blurring greyish shadow around text placed in the appropriate position on the image, now, though the text winds up in the right place on the image being overlayed, it is surround by a very dark, blocky shadow. Plus the shadow is clearly being trimmed. I'm trying to discover what sort of corrective I might apply to restore the lighter, gently blurring shadow I was able previously to achieve.

I do not understand especially well the technical workings of IM, rather having arrived at the incantation above mainly by looking over examples in the documentation and performing experiments based on those. So there may well be problems with what I previously put together that, only with the recent update, have begun to surface. Or perhaps some bug was introduced in this newer version of the software? Be that as it may, suggestions for accomplishing the intended aim will be appreciated.

PS Btw I get similar results (a dark blocky shadow surrounding the text) on this system when I try to run the sample command

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convert -background none -stroke black -fill white \
          -font Candice -pointsize 48 label:A -trim \
          \( +clone   -background navy   -shadow 80x3+3+3 \) +swap \
          -background none   -layers merge +repage  shadow_a.png
(taken from http://www.imagemagick.org/Usage/blur/#shadow)

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GeeMack
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Re: convert output changes with recent update

Post by GeeMack » 2019-05-31T13:01:22-07:00

jamtat wrote:
2019-05-31T12:47:09-07:00
A recent ImageMagick update (to version 7.0.8-47) on my system has resulted in production of errant results from a script I've been running for a few months now. The script overlays onto an image some text that I download from the internet at regular intervals, adding a blurred shadow effect to the text and positioning it on an image.
This is a bug that just appeared in v7.0.8-47. You can read more about it in THIS THREAD in the "Bugs" section of the forum.

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magick
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Re: convert output changes with recent update

Post by magick » 2019-06-01T05:24:52-07:00

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 @ https://www.imagemagick.org/download/beta/ by sometime tomorrow.

jamtat
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Re: convert output changes with recent update

Post by jamtat » 2019-06-01T09:28:02-07:00

Thanks for the quick response. Sounds like it may be awhile before the fix makes it into a stable release that will be found in my distro's (Arch) repository. Meantime, I'll either have to live with the current effect for a time or revert to a pre -47 IM release, correct?

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magick
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Re: convert output changes with recent update

Post by magick » 2019-06-01T11:29:22-07:00

-48 will be released today. Nudge Arch to upgrade or build -48 from source.

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