26 Dec
2018
26 Dec
'18
2 p.m.
On December 26, 2018 at 4:29 PM Mattis Lind via cctech
<cctech at classiccmp.org> wrote:
Finally I got hold of the sources for the PDP-11 SPACE WAR that was
submitted to DECUS by Bill Seiler.
The format is scans of the PAL-11S listing output. It is easy to crop the
image to only contain actual source. Then running OCR on it. Tried a few
online versions and tesseract.
The problem is that the paper that the listing is printed on has lines.
Very black lines. It makes the OCR go completely crazy. Source lines
without black lines OCR ok. The others do not. The files need massive
amount of manual intervention.
Does anyone have an idea how to process files like this?
A good way to remove the black lines?
There are only 19 source files with three or four pages each so I don't
think it makes sense to try to train tesseract to do it (training tesseract
seems to be a huge undertaking).
https://i.imgur.com/dvY973s.png
/Mattis
One thing you might try is to pull the scan images into matlab/gnu octave
and do a 2d FFT, remove the frequency band of the lines, inverse fft, and save. I've
had good luck removing regular patterns of noise from images that way.
Will
"He may look dumb but that's just a disguise." -- Charlie Daniels
"The names of global variables should start with // " -- https://isocpp.org
