Joining or merging a PDF file may sound easy, and it is. However, sometimes we would like to keep or preserve each file orientation when joining multiple PDFs with different size.
When I first tried joining such files with pdfjoin, all the files after the first one got rotated. I’m not sure, but I think it might be because of differences on files that I was working on.
But I solved my problem with –rotateoversize false parameter.
pdfjoin --rotateoversize false FILE_1.pdf FILE_2.pdf FILE_3.pdf -o Joined_file.pdf