Tagging images (metadata)

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?".
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Mahroun
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Tagging images (metadata)

Post by Mahroun »

Hello,

Recently I started writing keywords to my images using convert -set Keywords "%Keywords%" command.
I just noticed that other original metadata properties are lost, is there a way to prevent that? I just want to add keywords/tags to images and keep the rest as original as possible, including image quality.
Also, -set Keywords "%Keywords%" seems to work on PNG but not on JPG images.
Can someone with more experience give me an advice on tagging best practices? Someone told me that writing tags to -comment property is better.

TIA
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fmw42
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Re: Tagging images (metadata)

Post by fmw42 »

I am not an expert on JPG or PNG and you should wait to hear back from the IM developers, but according to http://www.imagemagick.org/Usage/basics/#settings in the Properties section, it says:

"Users can use Set to set or change these, as long as the 'key' does not correspond to some known 'attribute'."

So I assume that keyword is a particular attribute of JPG, though I do not know that for a fact. It could be a bug in the JPG writer?

On the other hand, I believe that -set comment is more globally allowed in IM as is -set label.

Before your post, I had not heard about any -set keyword property. But I can confirm that is does work on PNG but not JPG in IM 6.9.3.0 Q16 Mac OSX.

P.S. Always best to provide your exact command line, IM version and platform when asking questions, since syntax may differ. See viewtopic.php?f=1&t=9620

P.S. This does work in JPG

Code: Select all

convert image -set comment: keywords: "one two three" result.jpg
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