A tool for document merging. If you only have a scanner feeder that can only scan one side at a time this is for you.
tl;dr this is how it works
pdf1=['p1', 'p3', 'p5', 'p7', 'p9']
pdf2=['p2', 'p4', 'p6', 'p8', 'p10']
merged=['p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', 'p8', 'p9', 'p10']
./pdfMerger.py <inputDir1> <inputDir2> <inputDir3>...Put 2-3 pdfs in a directory, inside the directory, name the pdf with the page that comes first a.pdf, the other one b.pdf. Add another one called cover.pdf if you doc or book has a cover.
If you have to resolve to this tool, there is a great chance that one of your original pdfs are in reverse order. In order to reverse the input pdf, simply add -r right before .pdf.
For example
a.pdf = ['p1', 'p3', 'p5', 'p7', 'p9']
b-r.pdf = ['p10', 'p8', 'p6', 'p4', 'p2']
cover.pdf = ['c0', 'c1']
merged=['c0', 'p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', 'p8', 'p9', 'p10', 'c1']
Another example
a-r.pdf = ['p9', 'p7', 'p5', 'p3', 'p1']
b-r.pdf = ['p10', 'p8', 'p6', 'p4', 'p2']
cover.pdf = ['c0'] # if there is only front cover and no back cover
merged=['c0', 'p1', 'p2', 'p3', 'p4', 'p5', 'p6', 'p7', 'p8', 'p9', 'p10']
It won't work if your feeder jammed and there are couple of pages missing, it was a bug, but then I made it a feature. This script checks input pdf lengths before processing, it allows
len("a.pdf") == len("b.pdf")
len("a.pdf") - len("b.pdf") == 1
It won't allow
len("a.pdf") < len("b.pdf")
inputDir
|-> a.pdf
|-> b.pdf
|-> cover.pdf
Output to same level of input directory, in a directory named output
pdfMerger.py
foo
|-> a.pdf
|-> b.pdf
|-> cover.pdf
bar
|-> a.pdf
|-> b-r.pdf
|-> cover.pdf
baz
|-> a-r.pdf
|-> b.pdf
|-> cover.pdf
output
|-> foo.pdf
|-> bar.pdf
|-> baz.pdf