scaling down an image gives red and blue shadows?

Post any defects you find in the released or beta versions of the ImageMagick software here. Include the ImageMagick version, OS, and any command-line required to reproduce the problem. Got a patch for a bug? Post it here.
espressocannon
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Re: scaling down an image gives red and blue shadows?

Post by espressocannon » 2017-11-16T12:22:54-07:00

I can try the -quiet, the only issue I have with that is it still freaks me out... wish I knew what the warnings meant... it looks like all my EXIF has been stripped from the images somehow, that's kind of lame.

How do I upgrade "JPEG" ? I apt installed libjpeg9 and it still says 80...

dcraw versions - Raw photo decoder "dcraw" v9.21

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fmw42
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Re: scaling down an image gives red and blue shadows?

Post by fmw42 » 2017-11-16T12:44:38-07:00

The warnings are about non-standard tags in the meta data. They should not be a worry as long as they say warnings. IM ignores those tags but reports them as warnings.

I am not a Linux user, so cannot tell you how to upgrade. You may have to remove the old JPG and reinstall IM after installing the new JPG. Be sure you install the new one in the same place as the old one, so that IM can find it.

snibgo
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Re: scaling down an image gives red and blue shadows?

Post by snibgo » 2017-11-16T13:47:32-07:00

I published a page yesterday about using dcraw with IM for processing NEF images, mostly about colour balance rather than brightness.

IM reads the NEF, and de-bayers etc, through a delegate. This is either dcraw or ufraw-batch (which is based on dcraw).

So the first question is: what delegate is the OP using? Run the command with "-verbose" to find out. Then find which version of the delegate is being used.
snibgo's IM pages: im.snibgo.com

snibgo
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Re: scaling down an image gives red and blue shadows?

Post by snibgo » 2017-11-16T14:27:49-07:00

The OP says "scaling down an image gives red and blue shadows?" So, what happens if the image isn't scaled down? Does that solve the problem?
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snibgo
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Re: scaling down an image gives red and blue shadows?

Post by snibgo » 2017-11-16T15:34:43-07:00

From _MG_9449.CR ...

IM v7.0.3-5 with dcraw 9.27 as delegate converts with no problem.

dcraw 9.27 by itself works with no problem.

BUT...

UFraw-batch 0.22 ("f:\web\im>ufraw-batch --output=xu.tiff --out-depth=16 --out-type=tiff _MG_9449.CR2") makes a tiff that IM, Gimp and Windows Photo Viewer can't read. IM reports an error "convert.exe: TIFF directory is missing required "ImageLength" field. `MissingRequired' @ error/tiff.c/TIFFErrors/562."
snibgo's IM pages: im.snibgo.com

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