Works for a single page file, probably
Although arguably rotation is not quite lossless, and the two could be
mutually exclusive anyway, so maybe this is it. Did not check in some
debugging changes (lossless=False, text debugging=True)
PyPDF seems to get merging wrong when one of the pages is rotated.
I'm not fully happy with this arrangement, as it effectively downloads
OCRmyPDF twice, not to mention the lengthy setup time overall.
Will need to try separate build/run images in the future, but now just
get it working again.
setuptools_scm barfs because it can't find the version, because Docker hub
retrieves the application from Github in a way that omits the necessary
details.
I suppose there is a certain logic to Docker only using the tagged
released versions from PyPI, so go with it. The other attractive option
is to nix setuptools_scm.
unpaper doesn't seem to be good at deskewing. It fails on test case
with a lot of italics. I think it also struggles on pages with a lot
of whitespace. Leptonica continues to shine here.
However, this is only a first crack at Leptonica. The leptonica module
should be redone to use cffi (more extensible).
Also considering the possibility of making all Lept calls in a forked
process to insulate the calling process from C code crashes and the
messy redirect of stdout/stderr to read Leptonica's errors.
I don't think the redirect is a huge problem as long as multiprocesses
rather than multithreads are used. The ruffus child process that is
handling a page is single threaded and will not be affected by the
redirection. It just feels dirty. The main reason to consider a child
process is crash isolation.
Add -f to force generation of the background image at the desired
oversample resolution. Our new behavior is to only send the oversampled
image to Tesseract while leaving the main page intact unless asked to
deskew, clean, etc.
James R. Barlow
jbarlow83
Sean Whitton