ASTC Texture Compression

ASTC Texture Compression

ARB extension	KHR_texture_compression_astc_hdr, KHR_texture_compression_astc_ldr

ASTC Texture Compression is a form of Texture Compression that uses variable block sizes, rather than a single fixed size. ASTC is intended to effectively obsolete all prior compressed formats, providing all of the features of the others plus more, all in one format.

Because of the variable block sizes, it can achieve greater data compression than S3 Texture Compression by using larger block sizes. But by using smaller block sizes, it can also achieve better visual quality than BPTC Texture Compression. It can handle both floating-point and integer data, like BPTC Texture Compression. ASTC has control over how many channels are stored, and it can compress channels individually, providing the functionality of Red Green Texture Compression. ASTC also supports compressed data in the sRGB Colorspace.

Of course, the downside is that ASTC is not widely available at present. It is available as an OpenGL extension, but it is not core OpenGL functionality.