4.1 KiB
DIY Book Scanner Workflow
Getting started
This set of scripts was written for the Text Laundrette workshop. The workshop takes place in the Publication Station, WDkA building.
Rotterdam, 03-02-2020
It is a workflow to turn the pictures from the DIY Book Scanner into a final OCRed PDF.
About the Workshop
DESCRIPTION
We will use a home-made, DIY book scanner, and open-source software to scan, process, and add digital features to printed texts brought by the participants to the workshop. Ultimately, we will include them in the “bootleg library”, a shadow library accessible over a local network.
Shadow libraries operate outside of legal copyright frameworks, in response to decreased open access to knowledge. This workshop aims to extend our research on libraries, their sociability, and methods by which we can add provenance to texts included in public or private, legal or extra-legal collections.
Participants should bring: a printed text, which they’d like to digitize and share.
##Dependencies
###Brew (MAC) or apt-get (LINUX)
You’ll need the command-line tools for Xcode installed.
xcode-select --install
After, install Homebrew.
ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
Run the following command once you’re done to ensure Homebrew is installed and working properly:
brew doctor
sudo apt-get install python3 python3-pip imagemagick poppler-utils
brew install python3 python3-pip imagemagick poppler-utils
###PIP3
sudo pip3 install pdf2image Pillow opencv-python pytesseract
##How to use
Add your pictures from the book scanner to the folder "/scans"
Make all the files executable.
sudo chmod 777 merge_scans.sh workshop_stream.sh marge_files.sh
In case you want to skip any of the scripts just comment out in the shell code, workshop_stream.sh.
###Increase Imagemagick resources
nano /etc/ImageMagic-6/policy.xml
ImageMagick comes with very low limits:
Resource limits:
Width: 16KP
Height: 16KP
Area: 128MP
Memory: 256MiB
Map: 512MiB
Disk: 1GiB
File: 768
Thread: 4
Throttle: 0
Time: unlimited
change /etc/ImageMagick-6/policy.xml to more sensible defaults:
Resource limits:
Width: 128KP
Height: 128KP
Area: 1.0737GP
Memory: 2GiB
Map: 4GiB
Disk: 8GiB
File: 768
Thread: 4
Throttle: 0
Time: unlimited
###RUN
In terminal run ./workshop_stream.sh
Wait :)
##Aditional information
The workflow follows these scripts, by successive order:
###Create 5 directories
mkdir split
mkdir rotated
mkdir ocred
mkdir bounding_box
mkdir cropped
###Merge the files in the directory scans
All the scans will be appended to one pdf called out.pdf
```bash ./merge_scans.sh ```###Burst the pdf in scans
Burst this pdf, renaming all the files so they can be iterated later.
```bash python3 burstpdf.py ```###Rotate the pdfs
The book scanner takes pictures of the pdfs, this scrip iterates through the odd and even pages rotating them to their original position.
```bash python3 rotation.py ```###Crop the bounding boxes
The pages are now in their original position, but they have a bounding box. This script iterates through them and crops the highest contrast area found.
```bash python3 bounding_box.py ```###Crop the mirror
The pages are now cropped, but the mirror is still visible in the middle.
```bash python3 mirror_crop.py ```###OCR
In this part we OCR the jpg files, turning these into PDFs.
```bash python3 tesseract_ocr.py ```###Merge all the files and create the pdf
The OCRed pages are now joined into their final PDF, your book is ready :)
```bash ./merge_files.sh ```## License The package is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).