It is currently Thu Jun 07, 2018 7:48 pm

All times are UTC - 8 hours [ DST ]




Post new topic Reply to topic  [ 5 posts ] 
Author Message
PostPosted: Thu Jan 05, 2017 1:46 pm 
Offline
User avatar

Joined: Thu Jun 13, 2013 12:07 pm
Posts: 1014
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 198 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: 73
Location: Liepaja, Latvia
thank


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: 1014
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 2117 times ]
Top
 Profile  
Reply with quote  
PostPosted: Sun Feb 11, 2018 4:20 pm 
Offline
User avatar

Joined: Thu Jun 13, 2013 12:07 pm
Posts: 1014
More about Premultiplied/Straight

Blender software is ok to convert either Straight or premultiplied image.
Just takes a bit of work.
Today I found thoriumknight from 2011:

https://thoriumknight.deviantart.com/ar ... -262526394

has a great software converter, that is very easy to use.
For all those images in example aero.msstyles
What this means is if you like some button and try and use it in Classic Shell skin, the converted image will look correct brightness.
See how the 2nd column transparent button looks brighter in the below picture. It corrected the RGB layer, so it matches like on real Windows Vista/7 start menu. :)

I tried it it works.
I just had to force Windows 10 to run the program, as it thought it is harmful.
I checked it with Malwarebytes, and Windows Defender. No threats were found.


Attachments:
His software in action.png
His software in action.png [ 13.34 KiB | Viewed 1776 times ]
Top
 Profile  
Reply with quote  
PostPosted: Sun Feb 11, 2018 5:58 pm 
Offline
User avatar

Joined: Thu Jun 13, 2013 12:07 pm
Posts: 1014
It makes the Vista taskbar on Classic Shell better looking
than using the unaltered one from MSstyles


Attachments:
Vista taskbar converted to straight.png
Vista taskbar converted to straight.png [ 327 Bytes | Viewed 1769 times ]
Vista taskbar untouched premultiplied.png
Vista taskbar untouched premultiplied.png [ 378 Bytes | Viewed 1769 times ]
Example taskbar better .png
Example taskbar better .png [ 51.98 KiB | Viewed 1769 times ]
Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 8 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


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.