Convert cals to dds Online: cals2dds

You can use Tom's Editor to easily convert images from
Continuous Acquisition and Life-cycle Support Type 1 .CALS to Direct Show Surface .DDS.
Tom's Editor is a free, online image manipulation and converter program.

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CALS

Continuous Acquisition and Life-cycle Support Type 1 is an image format with extension CALS.

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.