#http://0x2a.at/blog/2011/02/pdf_manipulation_on_the_cli/
#https://stackoverflow.com/questions/535794/how-can-i-combine-two-pdf-pages-show-up-on-the-same-page
pdfjam figure9aCCN4M.pdf figure9b.pdf --nup 2x1 --landscape --outfile figure9.pdf
The same can be achieved with the ImageMagick package:
montage *.pdf merged.pdf
尝试处理掉中间的空白：
可以先 pdfjam --trim '1cm 2cm 1cm 2cm' --clip true figure9b.pdf --outfile output92.pdf
https://tex.stackexchange.com/questions/446103/pdfpages-pdfjam-with-different-template-size
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https://tex.stackexchange.com/questions/79623/quickly-extracting-individual-pages-from-a-document
pdfjoin --paper a4paper --rotateoversize false
其他工具：
https://blog.seisman.info/merge-pdf/
https://superuser.com/questions/917190/merge-two-pdf-files-side-by-side-in-command-line
#Manipulating pdfs with pdfjam()
https://texblog.org/2015/10/07/combining-sub-figures-to-a-single-figure-for-submission-to-journal/
Other options to pdfnup include --pages, --paper, --orient, --trim裁剪, --delta间隔, --offset, --scale and --openright.
We can also use pdfnup simply to select pages from a PDF file:
pdfnup file1.pdf --nup 1x1 --pages 1,3,5-6 \
--outfile file1-selection.pdf
https://helpmanual.io/help/pdfjam/
pdfcrop input.pdf output.pdf
pdfjam figure10a.pdf figure10b.pdf figure10c.pdf figure10d.pdf --nup 2x2 --trim '0.1cm 2cm 0.1cm 2cm' --clip true --delta "0.001cm 0.001cm" --outfile figure104.pdf
pdfjam 201*.pdf --nup 2x4 --trim '0.1cm 8cm 0.1cm 8cm' --clip true --delta "0.001cm 0.001cm" --outfile figure.pdf
pdfcrop input.pdf output.pdf
自己提的问题还未解决
pdfjam: Merging multiple pdfs into one page without white space like this Merge two PDF pages into new one without blank spaces between text content
具体示例https://indico.cern.ch/event/489565/contributions/1999816/attachments/1217344/1778174/pdfjam.pdf
