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<translate> A ploop image file format is pretty simple.

  • Image consists of cluster blocks (default cluster block size is 1 MB).
  • First there are some cluster blocks with BAT (Block Allocation Table), then there are some cluster blocks with data.
  • First 64 bytes of the first cluster block is a header, described in ploop1_image.h
  • The rest of BAT is just an array of 4 byte slots.
  • If a slot N contains value M, then a request to a cluster-block N of a /dev/ploopXXX device is redirected to a cluster-block M in an image file. N is counted from 0, while M is counted from 1 (0 means block is not yet allocated).

For the rest of the story, see sources. </translate>