If used ASTC without multiply alpha channel for all color except white images in Qml scene filled color rectangle. In Qt 3D Studio same astc looks nice. White image looks fat.
If used ASTC with multiply alpha channel color image is changed and appears border.
I made tool for viewing images \\psaftp.harman.com\FTP\qt\ftp_data\From_Harman\Astc_qml\TestApp
Need compiler this tool with Qt 5.13 or later.