Friday, February 27, 2015

How to process the scanned images to create a new book

We want to get the book back into publication.  Print-on-demand provides this capability.  So the problem is how to create the Print-on-demand input.

We have a scanned image of the original book.  We have both 300 dpi and 600 dpi scanned images, from Copy No. 23.  So one approach would be just to reprint these scanned images.  But these images are not very good.  We would like to clean them up first.

The first problem is that the pages are aging.  It appears that the paper that was used for the 1953 printing was not "acid-free", and so the paper is changing color and deteriorating.  The scans show a marked change in the paper to a brown, pink, salmon color.  If we use a black/white scan, instead of color, it's a dull grey over everything.

And then there are imperfections in the printed text itself.  For example, we have isolated the 5 occurrences of "The" on page 3 of the book, and we get:






Notice that the characters are all subtlety different.  This is a property of the inherent analog nature of the 1953 printing process.  Each instance of each character is slightly different.  Of course, some of this variation might also be the result of the scanning process.  We want to replace each of these different characters with one "ideal" image, a perfect "T" followed by a perfect "h" followed by a perfect "e".

But what is a perfect image? One approach would be to go back to 1953 and look at the definition of these characters then, but I can't do that.  What I can do is "merge" these 5 instances of these characters into one "average" character.  If we do that, we get:


We can then use a font editor to clean these up, and re-run the replacement of the characters with these newer clean copies to get:



Notice that this requires a certain amount of design skill.  Does the "e" in the cleaned-up version look too fat?  Or are the "T" and "h" too thin?

 There are other issues that need to be fixed too.  Some of the pages are scanned slightly off of horizontal, and we will want to re-level the lines, so that they are perfectly horizontal.


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