PNG files in contacts sheets

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puck

PNG files in contacts sheets

Post by puck »

PNG files do not appear with their transparency in the contact sheets it shows black square pieces around the borders of the object, do not understand, i had this problem too when displaying and solved it by changing the background colour, but there nothing works ! And the pity is that with my old computer, i did not have this kind of problem, mystery ... can someone help me, try to make a contact sheet with some PNG files may be .... thks puck
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xnview
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Re: PNG files in contacts sheets

Post by xnview »

puck wrote:PNG files do not appear with their transparency in the contact sheets it shows black square pieces around the borders of the object, do not understand, i had this problem too when displaying and solved it by changing the background colour, but there nothing works ! And the pity is that with my old computer, i did not have this kind of problem, mystery ... can someone help me, try to make a contact sheet with some PNG files may be .... thks puck
Yes, currently bitmap with alpha are loaded without it for contact sheet!
Pierre.
Guest

png in contact sheet

Post by Guest »

Iam confused by answer, is there a way to have transparency show properly on PNG image in contact sheet.

If there is, can you share a step by step process to make it happen.
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Drahken
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Post by Drahken »

If I understand correctly, he's saying that PNGs which use alpha transparency will always loose their transparency in contact sheets in the current version of xnview.
Do your PNGs use alpha transparency or single color (gif-like) transparency? If they're 8bit images (ie, 256 colors or less), it's safe to assume they're single color transparency. If they're 24 or 32bit images (16mil+ colors, truecolor, etc), it's safe to assume they're alpha transparency.
Butterfly

Post by Butterfly »

Was there ever a solution for this?
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xnview
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Post by xnview »

Butterfly wrote:Was there ever a solution for this?
I'll fix it in next release
Pierre.
ravencrow
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Re: PNG files in contacts sheets

Post by ravencrow »

hey, I know it's and old topic, but I can't found any new topic related to this.
I have the last version, and still can't select transparent background for creating contact sheets, there's any way?
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xnview
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Re: PNG files in contacts sheets

Post by xnview »

ravencrow wrote:hey, I know it's and old topic, but I can't found any new topic related to this.
I have the last version, and still can't select transparent background for creating contact sheets, there's any way?
What do you means by transparent background?
Pierre.
Yincognito
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Re:

Post by Yincognito »

xnview wrote: Tue Aug 26, 2008 8:28 am
Butterfly wrote:Was there ever a solution for this?
I'll fix it in next release
xnview wrote: Wed Mar 06, 2013 3:25 pm
ravencrow wrote:hey, I know it's and old topic, but I can't found any new topic related to this.
I have the last version, and still can't select transparent background for creating contact sheets, there's any way?
What do you means by transparent background?
So, it's 2021, 14 years after this topic was started, ImageMagick (also free) preserves transparency when doing contact sheets, Photoshop does it too since a good couple of years, is XnView / XnViewMP ever going to implement this or not? Is there a clear answer to this, you know, one that you can abide by and follow the promise? :?

I personally like your program very much otherwise - just converted 100 000+ PNGs to WEBPs with your software (XnViewMP) and thought about grouping those in fewer contact sheets but I need transparency to be preserved while creating the sheet. Sure, I can do it in a Photoshop batch driven process, but it would be nice if XnViewMP would be able to do it as well.
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xnview
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Re: Re:

Post by xnview »

Yincognito wrote: Tue Nov 02, 2021 7:03 pm So, it's 2021, 14 years after this topic was started, ImageMagick (also free) preserves transparency when doing contact sheets, Photoshop does it too since a good couple of years, is XnView / XnViewMP ever going to implement this or not? Is there a clear answer to this, you know, one that you can abide by and follow the promise? :?

I personally like your program very much otherwise - just converted 100 000+ PNGs to WEBPs with your software (XnViewMP) and thought about grouping those in fewer contact sheets but I need transparency to be preserved while creating the sheet. Sure, I can do it in a Photoshop batch driven process, but it would be nice if XnViewMP would be able to do it as well.
XnView MP can create contact sheets from transparent PNGs, if you have a problem please send some PNG samples and what you would like as output?
Pierre.
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Re: Re:

Post by Yincognito »

xnview wrote: Thu Nov 04, 2021 2:18 pmXnView MP can create contact sheets from transparent PNGs, if you have a problem please send some PNG samples and what you would like as output?
Yes, XnViewMP can indeed create contact sheets from transparent PNGs, it just can't create contact sheets to a transparent PNG (i.e. the output doesn't have a transparent background like the inputs).

For simplicity, I have these 2 input images (they are basically the same image but with different names, notice their transparent background):
129599 001.png
129599 002.png
In Photoshop CS6 - used just for comparison - I can do File / Automate / Contact Sheet II (without flattening layers and such):
PSCS6 Contact Sheet II.jpg
then delete the opaque background layer:
PSCS6 Delete Background Layer.jpg
followed by File / Scripts / Flatten All Masks (this step is optional, mentioned only for reference):
PSCS6 Flatten All Masks.jpg
and I get the contact sheet with a transparent background - just like the original images used as inputs were:
ContactSheet-001 PSCS6.png
However, even if I try to trick XnViewMP into using a completely transparent image as a background image (unchecked here, but I tried):
XnViewMP Create Contact Sheet.jpg
the background of the output image or contact sheet is always opaque, and not transparent like the result from Photoshop above:
ContactSheet-001 XnViewMP.png
In other words, I guess XnViewMP flattens the input images before creating the output image, therefore the transparent background is lost for the resulting contact sheet. Or something along these lines anyway. You can easily download the contact sheet samples above and use a checkboard pattern as background in XnViewMP to see the difference.

All I'm saying is that it would be nice if XnViewMP would allow preserving the transparency of the original images within the newly created contact sheet. It doesn't have to be by default, it could be optional, of course.
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Yincognito
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Re: Re:

Post by Yincognito »

xnview wrote: Thu Nov 04, 2021 2:18 pmXnView MP can create contact sheets from transparent PNGs, if you have a problem please send some PNG samples and what you would like as output?
Ok, just discovered that XnViewMP can actually do what I wanted, it's just that you have to choose Join Images to a Mosaic or Collage instead of creating a Contact Sheet:
Join Images To Mosaic.png
The result has a transparent background, just like the input images:
Strip (Join Images).png
I take back what I said above, it was my mistake for not looking at all the possibilities, but then I had no idea of the differences between creating a contact sheet and joining images in a mosaic/collage in XnViewMP. :?

Thanks for replying, Pierre - sorry for the misunderstanding, and congratulations for your great program. Keep it going!! :wink:
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