I have a pdf file that was made into a booklet format. It is meant to print on A4 paper in landscape orientation; here are two pages in the pdf, which should correspond to four pages in the actual book.
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| (1) | (3) |
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| (4) | (2) |
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The bracketed numbers correspond to the order of the individual pages.
I know that there are all sorts of commands (pdfbook, pdfnup, etc.) on linux (which was probably used to make this booklet in the first place). How do I 'unbook' it---that is, I'd like to make a pdf document from this where each individual page of the final product is an individual page of the pdf, ordered in the usual way.
Edit
Thanks to Gilles, I managed to use the following code:
import copy, sys
from pyPdf import PdfFileWriter, PdfFileReader
input = PdfFileReader(sys.stdin)
output = PdfFileWriter()
second_half = []
for i in range(0,input.getNumPages()):
p = input.getPage(i)
q = copy.copy(p)
print >> sys.stderr, 'splitting page',i
print >> sys.stderr, '\tlowerLeft:',p.mediaBox.lowerLeft
print >> sys.stderr, '\tupperRight:',p.mediaBox.upperRight
p.mediaBox.upperRight = (ur[0], (bl[1]+ur[1])/2)
p.mediaBox.lowerLeft = bl
q.mediaBox.upperRight = ur
q.mediaBox.lowerLeft = (bl[0], (bl[1]+ur[1])/2)
if i % 2 == 0:
output.addPage(p)
qold = q
else:
output.addPage(q)
output.addPage(qold)
output.addPage(p)
output.write(sys.stdout)