Alpha channel transparency

Ideas for improvements and requests for new features in XnView Classic

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Drahken
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Joined: Sun Apr 10, 2005 4:29 pm

Alpha channel transparency

Post by Drahken »

I had simply assumed that xnview supported alpha channel transparency when viewing images, but it appears that it doesn't. Is there some obscure option to enable it? If not, consider this a feature request.
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xnview
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Re: Alpha channel transparency

Post by xnview »

Drahken wrote:I had simply assumed that xnview supported alpha channel transparency when viewing images, but it appears that it doesn't. Is there some obscure option to enable it? If not, consider this a feature request.
You can view alpha channel in menu View/Show Mask
Pierre.
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Drahken
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Post by Drahken »

Hmm... 2 issues with that....
1) The option is greyed out in all 3 installations I have of xnview (1.7, 1.803, 1.82alpah (without WIA). However, I have a copy of xnview.exe in a zip file by itself, and when I run it, the option works. Any idea what's going on with that??
2) That's not what I meant. That will show the mask itself, but it won't show the image with the alpha transparency. It shows the image with no transparency at all, or shows the mask alone, but doesn't render the image with the alpha transparency.
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xnview
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Post by xnview »

Drahken wrote:Hmm... 2 issues with that....
1) The option is greyed out in all 3 installations I have of xnview (1.7, 1.803, 1.82alpah (without WIA). However, I have a copy of xnview.exe in a zip file by itself, and when I run it, the option works. Any idea what's going on with that??
So it's not a 32 bits picture??
2) That's not what I meant. That will show the mask itself, but it won't show the image with the alpha transparency. It shows the image with no transparency at all, or shows the mask alone, but doesn't render the image with the alpha transparency.
You have merge with alpha
Pierre.
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Drahken
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Post by Drahken »

1) It should be, considering it has an alpha channel, but it seems to only be 24bit. This is the image in question: http://allspark.net/cypherswipe/xnview- ... shadow.png
Why would an installed version of xnview have the option greyed out, but the exact same version of the prog when run from within a zip file works?

2) That just removes the alpha portion entirely, merging it into the background as though it never existed.

How xnview normally shows it:
Image
With view mask turned on:
Image
With mask merged:
Image
The way the image should appear:
Image

Edit: I was just taking another look through the options and found that read->PNG->compose with alpha wasn't checked. Checking it produced this (still incorrect) result:
Image

Edit 2: I just tried to do the view mask/combine alpha after turning this option on, and found it greyed out. After going back to the installed version and unchecking this option, the view mask/combine alpha are no longer greyed out. At least this answers the one question.
eweryboooody
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Post by eweryboooody »

Ahhh!! you really already planned to do the combine alpha-thing with the set backgroundcolor??! Great Great Great!!! :P *jump*

I think this also belongs onto a Hotkey like "M" for show alpha mask.

furthermore: I'd suggest to add an option to keep combine alpha checked when switching to next image.


btw: hmmm maybe sooner or later a hotkey-editor is needed? :?