Enable PREVIEW pseudo format

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kiloreux
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Enable PREVIEW pseudo format

Post by kiloreux »

I am installing imagemagick, and having everything set up properly. The only problem is that PREVIEW format is not there as well as few other formats such as GBR, GRB, RBG and BRG. Those formats we used to have them in version 6. Now with version 7.0.4-10, I can't have them. Any help is much appreciated.
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fmw42
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Re: Enable PREVIEW pseudo format

Post by fmw42 »

According to the format page for IM 6, there was never any GBR, GRB, and BRG formats, only RGB. Perhaps that was an undocumented feature for raw images? I cannot say since I never used raw format images before. But you can create an RGB format and then swap channels afterwards.

However, there is a PREVIEW in both IM 6 and IM 7, but the option -preview does not work in IM 7.

IM 6.9.8.10 Q16 (works fine)

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convert logo: -preview oilpaint PREVIEW:tmp.png

IM 7.0.6.1 Q16 (fails)

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magick logo: -preview oilpaint PREVIEW:tmp.png
magick: unrecognized option `-preview' at CLI arg 2 @ error/operation.c/CLISettingOptionInfo/1235.

I will report this as a bug.
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GeeMack
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Re: Enable PREVIEW pseudo format

Post by GeeMack »

fmw42 wrote: 2017-07-11T15:05:24-07:00I will report this as a bug.
I ran this command with v6.9.7-6 in Windows and v6.7.7-10 in bash....

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convert -list format | grep PREVIEW
The output is this (or similar) in each case...

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  PREVIEW* -w-   Show a preview an image enhancement, effect, or f/x
With v7.0.6-0 "magick" instead of "convert" there is no output.
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fmw42
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Re: Enable PREVIEW pseudo format

Post by fmw42 »

It is not PREVIEW that is missing, but -preview which is needed by PREVIEW. See http://www.imagemagick.org/script/formats.php#pseudo where it says:

"PREVIEW W Show a preview an image enhancement, effect, or f/x Creates a preview montage of images prepared over a parametric range in order to assist with parameter selection. Specify the desired preview type via the -preview option)."

See http://www.imagemagick.org/script/comma ... hp#preview
kiloreux
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Re: Enable PREVIEW pseudo format

Post by kiloreux »

The problem with that is that even when typing

> convert -list format | grep PREVIEW

I get nothing in return. The PREVIEW is not listed in the format list.
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fmw42
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Re: Enable PREVIEW pseudo format

Post by fmw42 »

That is because it is not an image format, but a pseudo-image format that only Imagemagick provides. See http://www.imagemagick.org/script/formats.php#pseudo
kiloreux
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Re: Enable PREVIEW pseudo format

Post by kiloreux »

If that's the case, i don't understand why I can see PLASMA PANGO HALD and all other pseudo formats, except that PREVIEW one?
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fmw42
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Re: Enable PREVIEW pseudo format

Post by fmw42 »

Looks like IM is including pseudo-image formats in the list of formats. So I would say that it is just an oversight in the IM 7 docs. I will report that as a bug.
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