Convert jp2k to dds Online: jp2k2dds

You can use Tom's Editor to easily convert images from
JPEG 2000 .JP2K to Direct Show Surface .DDS.
Tom's Editor is a free, online image manipulation and converter program.

Go to Tom's Editor

JP2K

JPEG 2000 is an image format with extension JP2K.

DDS

DDS are files invented by Microsoft to be used in games, mostly as textures. Images can be compressed to save space but the compression methods defined by DDS are all very fast in terms of coding and decoding.