Ico looking distorted when not highlighted

Question

I created an Ico that has multiple sizes in it, among which is the 48 x 48. I noticed that when the icon is not highlighted, it looks distroted and nothing like I designed it, but when I highlight it it looks good and exactly how I designed it. Here is an image to show what I mean:

Does anyone know why this happens?

Answer 1

Does your ICO have an alpha channel? That is, does it use graduated transparency per-pixel?

If you want it to look good against both light and dark backgrounds, it either has to be designed with a hard edge, or use alpha blending at the edges so that it looks nice.

If it looks like you're seeing some light or dark noise at the edges, then you probably need to make a version that supports alpha. This is sometimes referred to as ARGB (alpha/red/green/blue) or RGBA.

Answer 2

The icon is ok and it is the same in both cases.

The problem is that the borders are smoothed with a clear background, so the pixels near to a border and more lighted. This effect is almost not perceived when you have a light background (but still perceivable by a trained eye).