Here are the logs from test on embed metadata on many books (~1500) with all kind of formats at once:
http://pastebin.com/WqaPxT8q
Errors:
- Error: An internal error occurred.
- Error: The password used to open the PDF file was invalid. (checked pdf and it doesn't ask for password)
- Error: ePdfError_InvalidDataType (two files were correctly detected as non pdfs (because they had wrong extensions). one out of three was proper .pdf)
- Error: A number was expected but not found.
- IOError: [Errno 2] No such file or directory: u'/tmp/calibre_1.41.0_tmp_bn47ox/GGY5Ga_podofo_set_metadata/output.pdf'
- Error: No EOF Marker was found in the PDF file.
- Error: No XRef table was found in the PDF file.
EDITED: I can provide any of the files from logs.