[NTG-context] rotating some pages of a pdf

I'm using the following code, rotate.tex, to rotate all the pages of file.pdf, using: context --input=file.pdf --rotation=45 rotate.pdf rotate.tex ========== \getfiguredimensions [\getdocumentargument{input}] \starttext \dorecurse{\noffigurepages} {\startTEXpage \externalfigure [\getdocumentargument{input}] [page=\recurselevel, orientation=\getdocumentargument{rotation}] \stopTEXpage} \stoptext How could I use this code to rotate, say, the page five, 7º clockwise, and the page twenty, 15º counterclockwise? Many thanks in advance, -- Cesar