Convert dds to mgr Online: dds2mgr
You can use Tom's Editor to easily convert images from
Direct Show Surface
.DDS to MGR Window Manager bitmap .MGR.
Tom's Editor is a free, online image manipulation and converter program.
Go to Tom's Editor
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.
MGR Window Manager bitmap is an image format with extension MGR.