When I checked libharu and podofo, I checked the ability to save PDF files, but could not check the ability to load PDF and store them in a byte array.
Can I get a byte array From PDF image File with Podofo or libHaru?
If not, what is the proper library to open PDF and store it as a byte array? (except muPDF)
You mean to extract a bitmap image from a PDF file or to render PDF pages as images? Neither libharu nor podofo has the capability to read PDF docs. You should find a library that reads like PyPDF2.