In computer graphics, alpha channel represents transparency information of an image on a per-pixel basis. A value of 100% in the alpha channel gives a fully solid pixel and 0% provides full transparency. By selecting values of between 0% and 100%, pixels can be shown through the background (similar to glass), and therefore retain their anti-aliasing no matter the background.
What is the advantage, really?
This is one PNG image with alpha transparency placed on 2 different backgrounds:
And this image has been taken with WinSnap, and requires no post-processing. All that is required is to take instant screenshots using WinSnap and save high-quality images with alpha-channel.
This is very useful for multi-color web pages, when using a dynamic CMS, or publishing on a forum. Your screenshots will always look great!
Semi-transparent shadows look nice, but even more is possible with an image editor:
There are 2 different windows captured with WinSnap: open them with any image editor that supports PNG transparency and easily combine them into one image.
Learn more about WinSnap v2.0 features:
- Aero Glass capture with shadows and transparencies
- How to capture multiple windows on the screen
- Work faster with configurable External Tools