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iles in Custodians 2015

Don't let our knowledge be
crushed. Care for the libraries - care for the metadata - care for the backup.
Water the flowers - clean the volcanoes.

30 November 2015

Dusan Barok, Josephine Berry, Bodo Balazs, Sean Dockray, Kenneth Goldsmith,
Anthony Iles, Lawrence Liang, Sebastian Luetgert, Pauline van Mourik Broekman,
Marcell Mars, spideralex, Tomislav Medak, Dubravka Sekulic, Femke Snelting...

* * *

1. Lariviere, Vincent, Stefanie Haustein, and Philippe Mongeon. “[The Oligopoly of Academic Pu

iles in Medak, Sekulic & Mertens 2014

UBLIC LIBRARY OVERHEAD SCANNER

Written by:
Tomislav Medak
Dubravka Sekulić
With help of:
An Mertens

Creative Commons Attribution - Share-Alike 3.0 Germany

TABLE OF CONTENTS

Introduction
3
I. Photographing a printed book
7
I. Getting the image files ready for post-processing
11
III. Transformation of source images into .tiffs
13
IV. Optical character recognition
16
V. Creating a finalized e-book file
16
VI. Cataloging and sharing the e-book
16
Quick workflow reference for scanning and post-proce

and demanding process. Many factors can go wrong or produce
results of varying quality from book to book or page to page, requiring experience or technical skill
to resolve issues that occur. Cameras can fail to trigger, components to communicate, files can get
corrupted in the transfer, storage card doesn't get purged, focus fails to lock, lighting conditions
change. There are trade-offs between the automation that is prone to instability and the robustness
that is prone to become time consuming.
Y

indicate the design choices you have in the
process of planning your workflow and should help you make decisions on what design is best for
you situation.
Introducing book scanner designs
The book scanning starts with the capturing of digital image files on the scanning equipment. There
are three principle types of book scanner designs:
 flatbed scanner
 single camera overhead scanner
 dual camera overhead scanner
Conventional flatbed scanners are widely available. However, given that they r

er

More on this manual: steps in the book scanning process
The book scanning process in general can be broken down in six steps, each of which will be dealt
in a separate chapter in this manual:
I. Photographing a printed book
I. Getting the image files ready for post-processing
III. Transformation of source images into .tiffs
IV. Optical character recognition
V. Creating a finalized e-book file
VI. Cataloging and sharing the e-book
A step by step manual for Public Library scanner
This manual is pri

ove. This is a
two-camera overhead scanner, currently equipped with two Canon 1100 D cameras with EF-S 1855mm 1:3.5-5.6 IS kit lens. It can scan books of up to A4 page size.
The post-processing in this setup is based on a semi-automated transfer of files to a GNU/Linux
personal computer and on the use of free software for image editing, optical character recognition
and finalization of an e-book file. It was initially developed for the HAIP festival in Ljubljana in
2011 and perfected later at MaMa in

one such scanner, developed at the Hacker Space Bruxelles, is also included in
this manual.
The Public Library scanning process proceeds thus in following discrete steps:

1. creating digital images of pages of a book,
2. manual transfer of image files to the computer for post-processing,
3. automated renaming of files, ordering of even and odd pages, rotation of images and upload to a
cloud storage,
4. manual transformation of source images into .tiff files in ScanTailor
5. manual optical character recognition and creation of PDF files in gscan2pdf
The detailed description of the Public Library scanning process follows below.
The Bruxelles hacklab scanning process
For purposes of comparison, here we'll briefly reference the scanner built by the Bruxelles hacklab
(http://hackerspace

sing a page due to a distraction.
While scanning, move the cradle a bit to the left from time to time, making sure that the tip of Vshaped platen is aligned with the center of the book and the inner margin is exposed enough.

II. GETTING THE IMAGE FILES READY FOR POST-PROCESSING
Once the book pages have been photographed, they have to be transfered to the computer and
prepared for post-processing. With two-camera scanners, the capturing process will result in two
separate sets of images -- odd and e

coming from the left and right cameras respectively
-- and you will need to rename and reorder them accordingly, rotate them into a vertical position
and collate them into a single sequence of files.
a) Transferring image files
For the transfer of files your principle process design choices are either to copy the files by
removing the memory cards from the cameras and copying them to the computer via a card reader
or to transfer them via a USB cable. The latter process can be automated by remote operating your
cameras from a computer, however this can be done only with a certain number of Canon cameras
(http://bit.ly/16xhJ6b) that can be hacked to run the open Canon Hack Development Kit firmware
(http://chdk.wikia.com).
After transferring the files, you want to erase all the image files on the camera memory card, so that
they would not end up messing up the scan of the next book.
b) Renaming image files
As the left and right camera are typically operated in sync, the photographing process results in two
separate sets of images, with even and odd pages respectively, that have completely different file
names and potentially same time stamps. So before you collate the page images in the order how
they appear in the book, you want to rename the files so that the first image comes from the right
camera, the second from the left camera, the third comes again from the right camera and so on.
You probably want to do a batch renaming, where your right camera files start with n and are offset
by an increment of 2 (e.g. page_0000.jpg, page_0002.jpg,...) and your left camera files start with
n+1 and are also offset by an increment of 2 (e.g. page_0001.jpg, page_0003.jpg,...).
Batch renaming can be completed either from your file manager, in command line or with a number
of GUI applications (e.g. GPrename, rename, cuteRenamer o

eMagick, Nautilust Image Converter on GNU/Linux).
d) Collating images into a single batch
Once you're done with the renaming and rotating of the files, you want to collate them into the same
folder for easier manipulation later.

Getting the image files ready for post-processing on the Public Library scanner
In the case of Public Library scanner, a custom C++ script was written by Mislav Stublić to
facilitate the transfer, renaming, rotating and collating of the images from the two cameras.
The scr

create a subfolder in a local cloud storage folder (path: /home/user/Copy).
It transfers, renames, rotates the files, deletes them from the card and prompts the user to replace the
card with the one from the left camera in order to the transfer the files from there and place them in
the same folder. The script was created for GNU/Linux system and it can be downloaded, together
with its source code, from: https://copy.com/nLSzflBnjoEB
If you have other cameras than Canon, you can edit the line 387 of

6c048694a3043b158d62;hb=HEAD

III. TRANSFORMATION OF SOURCE IMAGES INTO .TIFFS
Images transferred from the cameras are high definition full color images. You want your cameras
to shoot at the largest possible .jpg resolution in order for resulting files to have at least 300 dpi (A4
at 300 dpi requires a 9.5 megapixel image). In the post-processing the size of the image files needs
to be reduced down radically, so that several hundred images can be merged into an e-book file of a
tolerable size.
Hence, the first step in the post-processing is to crop the images from cameras only to the content of
the pages. The surroundin

away, while the printed text will be transformed into black
letters on white background. The illustrations, however, will need to be preserved in their color or
grayscale form, and mixed with the black and white text. What were initially large .jpg files will
now become relatively small .tiff files that are ready for optical character recognition process
(OCR).
These tasks can be completed by a number of software applications. Our manual will focus on one
that can be used across all major operating systems -- ScanTailor. ScanTailor can be downl

irectory’ chose the folder where you stored the transferred and renamed photo images
- you can leave ‘output directory’ as it is, it will place your resulting .tiffs in an 'out' folder inside
the folder where your .jpg images are
- select all files (if you followed the naming convention above, they will be named
‘page_xxxx.jpg’) in the folder where you stored the transferred photo images, and click 'OK'
- in the dialog box ‘Fix DPI’ click on All Pages, and for DPI choose preferably '600

w you are ready to output the files. Just press 'Play' button under 'Output'. Once the computer is
finished processing the images, just do 'File' → 'Save as' and save the project.

IV. OPTICAL CHARACTER RECOGNITION
Before the edited-down graphic files are finalized as an e-book, we want to transform the image of
the text into an actual text that can be searched, highlighted, copied and transformed. That
functionality is provided by Optical Character Recognition. This a technically difficult task d

under the original graphic image of the text in
a PDF file.
With the help of other tools, OCR can be performed also against other input files, such as graphiconly PDF files. This produces inferior results, depending again on the quality of graphic files and
the reproduction of text in them. One such tool is a bashscript to OCR a ODF file that can be found
here: https://github.com/andrecastro0o/ocr/blob/master/ocr.sh
As mentioned in the 'before scanning' section, the quality of the original book will

t that works better with e-book readers, obviously you will have
to remove some of the elements that appear in the book - headers, footers, footnotes and pagination.

This can be done earlier in the process of cropping down the original .jpg image files (see under III)
or later by transforming the PDF files. This can be done in Calibre (http://calibre-ebook.com) by
converting the PDF into an ePub, where it can be further tweaked to better accommodate or remove
the headers, footers, footnotes and pag

and the PDF or DjVu export.
To do so, start gscan2pdf and open your .tiff files. To OCR them, go to 'Tools' and select 'OCR'. In
the dialog box select the Tesseract engine and your language. 'Start OCR'. Once the OCR is
finished, export the graphic files and the OCR text to PDF by selecting 'Save as'.
However, given that sometimes the proprietary solutions produce better results, these tasks can also
be done, for instance, on the Abbyy FineReader running on a Windows operating system running
inside t

rtual Box. The prerequisites are that you have both Windows and Abbyy FineReader
you can install in the Virtual Box. If using Virtual Box, once you've got both installed, you need to
designate a shared folder in your Virtual Box and place the .tiff files there. You can now open them
from the Abbyy FineReader running in the Virtual Box, OCR them and export them into a PDF.
To use Abbyy FineReader transfer the output files in your 'out' out folder to the shared folder of the
VirtualBox. Then start the VirtualBox, start Windows image and in Windows start Abbyy
FineReader. Open the files and let the Abbyy FineReader read the files. Once it's done, output the
result into PDF.

VI. CATALOGING AND SHARING THE E-BOOK
Your road from a book on paper to an e-book is complete. If you want to maintain your library you
can use Calibre, a free

art.
- ADVICE: The scanner has a digital counter. By turning the dial forward and backward,
you can set it to tell you what page you should be scanning next. This should help you to
avoid missing a page due to a distraction.

II. Getting the image files ready for post-processing
- after finishing with scanning a book, transfer the files to the post-processing computer
and purge the memory cards
- if transferring the files manually:
- create two separate folders,
- transfer the files from the folders with image files on cards, using a batch
renaming software rename the files from the right camera following the convention
page_0001.jpg, page_0003.jpg, page_0005.jpg... -- and the files from the left camera
following the convention page_0002.jpg, page_0004.jpg, page_0006.jpg...
- collate image files into a single folder
- before ejecting each card, delete all the photo files on the card
- if using the scanflow script:
- start the script on the computer
- place the card from the right camera into the card reader
- enter the name of the destination folder following the convention
"Name_Surname_Title_of_the_Book" and transf

r ‘input directory’ chose the folder where you stored the transferred photo images
- you can leave ‘output directory’ as it is, it will place your resulting .tiffs in an 'out' folder
inside the folder where your .jpg images are
- select all files (if you followed the naming convention above, they will be named
‘page_xxxx.jpg’) in the folder where you stored the transferred photo images, and click
'OK'
- in the dialog box ‘Fix DPI’ click on All Pages, and for DPI choose preferably '600

and tick on 'White
Margins'. Do the same for the back page.
- If there are any pages with illustrations, you can choose the 'Mixed' mode for those
pages and then under the thumb 'Picture Zones' adjust the zones of the illustrations.
- To output the files press 'Play' button under 'Output'. Save the project.
IV. Optical character recognition & V. Creating a finalized e-book file
If using all free software:
1) open gscan2pdf (if not already installed on your machine, install gscan2pdf from the
reposito

o under 'File' and select 'Save', edit the
metadata and select the format, save
If using non-free software:
2) open Abbyy FineReader in VirtualBox (note: only Abby FineReader 10 installs and works with some limitations - under GNU/Linux)
- transfer files in the 'out' folder to the folder shared with the VirtualBox
- point it to the readied .tiff files and it will complete the OCR
- save the file

REFERENCES
For more information on the book scanning process in general and making your own book scanner
please visit:
DIY Book Scanner: http://diybookscannnner.org
Hacker Space Bruxelles scanner: http:/

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