WARNING: XXXXXXXXX format is not supported, decompressing texture

Hi. I'm recently detected in build logs (cloud build and local build) strange warnings. After a some research I realised that these warnings appears on sprites with enabled compression.

For example:
RGB png file
"Texture type" - Sprite (2D and UI)
"Compression (Default)" - Normal Quality, Format Auto.

When I'm building project for Android or iOS (Mac OSX or Windows builds doesn't have such wanings) I'm receiving every time warnings on files with these settings.

And numbers always different. I created test script, attached to gameobject with SpriteRenderer component. After running build on iOS device I had seen in logs that texture is compressed - "PVRTC_RGB4".

Code (CSharp):

1. public class Test : MonoBehaviour
2. {
3.     private void Start()
4.     {
5.         var spr = GetComponent<SpriteRenderer>();
6.         Debug.Log(">>>>> " + spr.sprite.texture.format);
7.     }
8. }

For files with "Texture Type: Default" and compression I'm not receiving any warnings.

So, could anybody explain me what does these warnings means? And should I care about them? How handle with them?

Unity 2017.1.1f1

 

Did you find any solutions regarding this matter?

 

Nope... I have stopped temporarily my research of this problem.

 

From what I was able to find, it happens if you have files (textures) that are not compatible with compression format for the target you're compiling against.