Pdftk

pdf drehen

to rotate an pdf-file you scanned you will have to do
some steps...

1. uncompress the pdf-file (pdftk)
2. replace 'Rotate 0' by 'Rotate 180' using sed
3. re-compress the file

example:

pdftk scanned.pdf output temp_uncompressed.pdf uncompress

uncompress the scanned file

sed -i "s/Rotate 0/Rotate 180/g" temp_uncompressed.pdf

replace all occcurences of 'Rotate 0' by e.g. 'Rotate 180' or 90 or 240 ... whatever!

pdftk temp_uncompressed.pdf output final_pdffile_page1.pdf compress

re-compress the file

repeat this steps until all pages are rotated it's head up
now you have one pdf-file per page...

merge files together if you need it, to get only one pdf-file for all pages!
to do this you need ghostscript installed
look here: Ghostscript