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Hi friends,

  I have a question about DEM extraction. I had extracted DEMs from 1/2 in tapes. Now i have DTED data on a CD. I have tried to use the proceedure which
i had used in the case of the DEM extraction from tape drive, the following is
the first step.

dd [if=tapedev] ibs=input-block-size | m.dmaUSGSread top=value bottom=value left=value right=value output=name logfile=name
  
  My problem has been, when i use the above the output file has come out
to be empty. Is there a seperate proceedure for extracting DEMs from CDs. Can
anyone help!

Sree