When compressing certain textures with ASTC LDR we get corrupted results.
Source image:
Source image (1024x512 lightmap) can also be found attached to post or downloaded here:
https://dl.dropboxusercontent.com/u/7197208/images/lightmap_table-evening.png
When compressed in LDR Linear mode we get corrupted result: top part (2/3rds of image) is clear white and in the bottom source image is repeated 3 times:
When trying to compress image in LDR SRGB we get the following error:
Image is compressed correctly only in HDR mode.
This does not happen with other images, only certain ones (black-and-white lightmaps) are affected by bug.
Tested on Mali Texture Compression Tool versions 4.2.0 and 4.1.0.
Bug prevents us from using compressed ASTC textures in our Android app, its a shame because it provides excellent quality compared to ETC2 full of block artifacts.
For those who want to know how to flip, using imagemagick:
convert -flip <input.png> <output.png>
Thank you for explaining this. We'll use flipped source images.