I suggest you to use ImageMagick if you need a batch conversion from or to DDS format. Latest version (currently is 6.8.7-4) support DDS format for both read and write (sse here).
The syntax is very simple, you can convert a file at once:
convert myfile.png myfile.dds
Or you can convert all the files with a single command (assuming your files are png, for example):
mogrify -format dds *.png