It is currently Tue Jan 16, 2018 4:36 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 3 posts ] 
Author Message
PostPosted: Thu Jan 05, 2017 1:46 pm 
Offline
User avatar

Joined: Thu Jun 13, 2013 12:07 pm
Posts: 958
Premultiplied Alpha and not premultiplied images.


From what I see in the skinning tutorial, CSM does not use premultiplied images:
"For 32-bit images don't premultiply the alpha channel. If you don't know what "premultiply the alpha" means, never mind."


A lot of buttons, user picture frames, menu images from msstyles files have some type of premultiplied alpha in them.
It's some kind of merging, and throwing away pixels process. They appear darker in a photo program.

Example red color:

* Red pixels with a premultiplied alpha of 50% have 8bit RGBA value: 127,0,0,127

* Red pixels with a ………straight alpha of 50% have 8bit RGBA value: 255,0,0,127

What's puzzling to me is photo programs do this anyway, and a premultiplied, or not premultipled same image look same in editor.
I think MS multiplied with a different factor, to make it hard on us. :x

How to exactly undo premultiplied alpha image, so it can be used?
Beats the H%LL out of me, and everyone else.
Can only boost the brightness of all channels to get approximate look from original os.


Attachments:
Not premultiplied. examples.zip [1.15 KiB]
Downloaded 113 times
Top
 Profile  
Reply with quote  
PostPosted: Tue Jan 02, 2018 11:53 am 
Offline
User avatar

Joined: Tue Nov 21, 2017 10:52 am
Posts: 68
Location: Liepaja, Latvia
thank

_________________
♫♪.ılılıll|̲̅̅●̲̅̅|̲̅̅=̲̅̅|̲̅̅●̲̅̅|llılılı.♫♪


Top
 Profile  
Reply with quote  
PostPosted: Tue Jan 02, 2018 3:56 pm 
Offline
User avatar

Joined: Thu Jun 13, 2013 12:07 pm
Posts: 958
I found a free program later, that can switch between premultiplied and not premultiplied.
It is called Blender.

I never got around to trying the buttons I converted on an actual menu.
I had just used screenshots.

Here is example of the shutdown button that got set correctly for CSM:

; Shutdown button

Shutdown_selection=19
Shutdown_jump_selection=19
Shutdown_search_selection=19
Shutdown_selection_slices_X=5,14,4,3,14,5
Shutdown_selection_slices_Y=5,14,5

You can be the first to try it.


Attachments:
fixed premultiplied shutdown.png
fixed premultiplied shutdown.png [ 1.52 KiB | Viewed 138 times ]
Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 5 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group, Almsamim WYSIWYG Classic Shell © 2010-2016, Ivo Beltchev.
All right reserved.