Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
ALPHA BACKGROUND
#1
Okay so this happened out of the blue. Normally when I copy and paste something with an alpha background, the alpha part is clear so my background color only shows. Now for some reason it posts as black. I know most people will tell me to just set the black to the alpha color but this also messes up images that are already black and the alpha color change doesn't recognize. I didn't have this issue till today out of the blue and I didn't mess with any settings. This is what the image looks like online
   
this is how it looks when I copy and paste it.
   

The same problem happens even if I save the image and open as a layer as well.
Reply
#2
welcome to gimp-forum.net

-----------
edit: I might have misread the problem but the image posted, while it has an alpha channel also is completely solid - just green shapes and the black. I will attach that houston4.png made with black BG.
----------

What you have done there is take the advice too literally and added a solid black layer. Exporting as a png and the image is flattened and the layer then becomes part of the png.

The background (BG) color does come into it. The set BG color is used for the alpha mask used by applications to denote transparency. Some games etc might work best with black rather than the more usual white.

You can determine the colour used with applications such as ImageMagick but all you really need to know is
Does the transparency show in gimp (that checker pattern)
Is the BG set to black.

example - the two versions.

[Image: beEDkBD.jpg]

My advice, do not try and fix it, start again Wink


Attached Files Image(s)
   
Reply
#3
(02-01-2018, 12:12 PM)rich2005 Wrote: welcome to gimp-forum.net

-----------
edit: I might have misread the problem but the image posted, while it has an alpha channel also is completely solid - just green shapes and the black. I will attach that houston4.png made with black BG.
----------


My issue is the second image I posted is what the first image looks like when I copy it to gimp. I want it to look like the first image. The issue with me having the second image when I paste it is I can’t select the image of the guns to keep them. Gimp can’t tell the difference when it gives me the black background :/.

To reidderate: I’m trying to post image 1 which has a transparent back ground but it keeps coming out as image 2 which is hard for me to use.
Reply
#4
Im not exactly sure what is going on here, but the "trick" is not to copy but save the image.

I get the same black for transparency when i copy and paste, but i get the expected transparency when i save and open.

As far as i understand 'Flatten' removes the alpha channel, and according to what my background colour is set to (black or white), it determines what colour is swapped for the alpha (as rich said above).
Reply
#5
Might be as Espermaschine posted

However: Yes, I do not understand.

What you have given is 2 images, which as layers looks like this: https://i.imgur.com/rX9Bonc.jpg

both have an alpha channel but the top layer is all solid colour, no transparent areas.

Do you want something like this (changed colour for emphasis) : https://i.imgur.com/a04OY8d.jpg
Reply
#6
The attached PNG is an all black image with a disk of opaque pixels (in other words, what you see is just defined by the alpha channel. What happens when you copy/paste it? And can you be more explicit to what you paste (how to you copy/cut), and what is the target (image editor, mode/type of image (RGB, indexed...))?


Attached Files Image(s)
   
Reply
#7
When I copy and paste the first image into Gimp it shows with a transparent background; the transparency indicated by a checquer board pattern.

Just a thought: has your Gimp been inadvertently set to show transparency as black? If so, change to the check pattern.


Attached Files Thumbnail(s)
   
Reply
#8
(02-01-2018, 01:37 PM)Blighty Wrote: Just a thought: has your Gimp been inadvertently set to show transparency as black? If so, change to the check pattern.

My Display Preferences look exactly as in Blighty's screenshot, so nothing was changed.
When i right click Copy Image and Edit: Paste ofnuts image from Chrome into Gimp, its completely black. The Image Mode is set to RGB, it has an alpha channel.

Again: when i save and open instead, it has transparency....
Reply
#9
(02-01-2018, 01:56 PM)Espermaschine Wrote: When i right click Copy Image and Edit: Paste ofnuts image from Chrome into Gimp, its completely black. The Image Mode is set to RGB, it has an alpha channel.

Again: when i save and open instead, it has transparency....

Could be a bug in your Chrome, possibly Windows-related. Copy/paste the image from Firefox or Chrome keeps the transparency.
Reply
#10
Guys I have tried saving and opening the image in gimp. Still gives me the black black background where I’m supposed to have transparency. I’ll try the setting changed mentioned and let you know the results.

   
this is my thumbnail settings
   
This is the image when I post it into gimp.
   
This is this original image posted with the alpha background clearly shown. 

I used to be able to right click and copy any of the icon on this site:
https://overwatchleague.com/en-us/schedule


and it would paste with an alpha background not this black one. I clearly want the guns shown and it's hard with the black background shown.

Hopefully this helps clear up my issue and if not I'll reread your comments and try them.

(02-01-2018, 02:38 PM)Ofnuts Wrote:
(02-01-2018, 01:56 PM)Espermaschine Wrote: When i right click Copy Image and Edit: Paste ofnuts image from Chrome into Gimp, its completely black. The Image Mode is set to RGB, it has an alpha channel.

Again: when i save and open instead, it has transparency....

Could be a bug in your Chrome, possibly Windows-related. Copy/paste the image from Firefox or Chrome keeps the transparency.

That explains it... Firefox it pastes normally so it must be my chrome even though it's updated.
Reply


Forum Jump: