pdf2c4 < $FILENAME

* pdf2c4 dumps images out of g4-compressed PDF, like pdfimages but 
  faster (and cruder), without decompressing g4
* swap swaps image, decompresses g4 via TIFFlib, but without unfolding 
  8-pixel per byte format, recompresses
* slice slices TIFF into two parts at given lines, decompresses g4 via TIFFlib, 
  but without unfolding 8-pixel per byte format, recompresses
* rotate rotates TIFF clockwise, decompresses g4 via TIFFlib, but without 
  unfolding 8-pixel per byte format, recompresses
* rotate-ccw rotates TIFF counterclockwise, decompresses g4 via TIFFlib, but without 
  unfolding 8-pixel per byte format, recompresses. rotate-ccw is slightly faster
  that rotate, because less bit-shifting involved.

Files are kept in 8-pixels per byte format (*not* expanded).
When working with non-8 divisible image lengths, rotate has had most testing.
more on usage see eg ../script/pdf_swap, ../script/sliceupisright ... , ../script/rotateupisright