Raspberry Pi project created to assist reading books in different languages. The goal of the RPi_Translator is to quickly provide a translation or English definition of a word so that you can spend less time looking up what a word means, and more time reading!
I have a long way till the finished product, so if you are interested in helping accelerate the learning process through reading, please feel free to reach out to me!
The following picture is the current hardware setup. The final goal is to to create a smaller, portable design. For now, the camera is held in a housing made of Lego bricks.
Closeup of camera housing:
To get an english translation or definition of a word, bring the pointer underneath the particular word and press the button.
The following pictures visually demonstrate the word segmentation and final output for the dictionary:
The following pictures visually demonstrate the word segmentation and final output for the translator (Serbian (Latin) -> English):
- For installing OpenCV on the Raspberry Pi refer to these useful resources:
- http://docs.opencv.org/trunk/d7/d9f/tutorial_linux_install.html
- https://github.com/MicrocontrollersAndMore/Raspberry_Pi_2_and_OpenCV_3_Tutorial_Part_1/blob/master/Raspberry%20Pi%202%20%2B%20OpenCV%203%20Cheat%20Sheet.txt
- http://www.pyimagesearch.com/2015/12/14/installing-opencv-on-your-raspberry-pi-zero/
Tesseract versions and the minimum version of Leptonica required:
| Tesseract | Leptonica | Ubuntu |
|---|---|---|
| 4.00 | 1.74.0 | Must build from source |
| 3.04 | 1.71 | Ubuntu 16.04 |
| 3.03 | 1.70 | Ubuntu 14.04 |
| 3.02 | 1.69 | Ubuntu 12.04 |
I wanted to install the most recent version of Tesseract so I built it from source. The Tesseract GitHub page has good instructions (https://github.com/tesseract-ocr/tesseract/wiki/Compiling), but I will show the main steps I took as another reference.
- Building Leptonica from source: https://tpgit.github.io/UnOfficialLeptDocs/leptonica/README.html#building-leptonica
- The latest version can be found here : http://www.leptonica.org/download.html
- cd ~/Downloads
- wget http://www.leptonica.org/source/leptonica-1.74.1.tar.gz
- gunzip leptonica-1.74.1.tar.gz
- tar -xvf leptonica-1.74.1.tar
- cd leptonica-1.74.1/
- ./configure [build the makefile]
- sudo make [builds the library and shared library versions of all the progs (this took a while!)]
- sudo make install [as root; this puts liblept.a into /usr/local/lib/ and all the progs into /usr/local/bin/ ]
- In addition to Leptonica, the following libraries are needed:
- sudo apt-get install autoconf automake libtool
- sudo apt-get install autoconf-archive
- sudo apt-get install pkg-config
- sudo apt-get install libpng12-dev
- sudo apt-get install libjpeg8-dev
- sudo apt-get install libtiff5-dev
- sudo apt-get install zlib1g-dev
- Steps for tesseract:
- git clone https://github.com/tesseract-ocr/tesseract.git
- cd tesseract
- ./autogen.sh
- ./configure --enable-debug
- LDFLAGS="-L/usr/local/lib" CFLAGS="-I/usr/local/include" make
- sudo make install
- sudo ldconfig
- Download the languages you are interested in:
- Set an environment variable to point to the parent directory of the tessdata directory. The tessdata directory stores the data file(s) of the language(s) you are interested in.
- sudo nano .bashrc
- Add a line such as: export TESSDATA_PREFIX=/home/pi/tesseract, and then close/reopen your terminal
- Download language data, e.g. wget https://github.com/tesseract-ocr/tessdata/raw/4.00/eng.traineddata
- Move it to the tesdata directory: mv eng.traineddata $TESSDATA_PREFIX/tessdata
- Test if tesseract was properly downloaded:
- In the command line try tesseract –list-langs and you should see the languages you downloaded earlier
- Take a sample image and try: tesseract sample_image.jpg output.txt
- Python wrapper for the tesseract-ocr API (tesserocr)
- https://github.com/sirfz/tesserocr
- Note that Cython is required for building
- For now Microsoft provides a translate service that is free for public use. Note that subscriptions, up to 2 million characters a month, are free. Translating more than 2 million characters per month requires a payment.
- Sign up for a Microsoft Azure Marketplace API Key. I chose to store the key as an environment variable.
- If you are using python, a useful Microsoft Translate API wrapper can be found here: https://github.com/wronglink/mstranslator
- The Merriam-Webster Dictionary API is free as long as it is for non-commercial use, usage does not exceed 1000 queries per day per API key, and use is limited to two reference APIs.
- Create an account here https://www.dictionaryapi.com/