gpyocr 0.4

Python wrapper for Tesseract OCR and Google Vision OCR

Python wrapper for Tesseract OCR and Google Vision OCR to perform OCR on images and get a confidence value of the results.

Both OCR engines are Google’s products. Tesseract is an open source software that needs some tweaks to get good results, especially if performed on images with poorly defined text. Google Vision OCR engine is a commercial product with much better performance, allowing you to skip the pre-processing jobs on the images.

Only Python 3.6 is supported.

Usage

The gpyocr module have two main functions:

• tesseract_ocr(image, lang='', psm=None, config=''): it returns a tuple (text, confidence) obtained with Tesseract. The parameters are the same of the command-line Tesseract tool except for the output file.

• google_vision_ocr(image, langs=None): it returns a tuple (text, confidence) obtained with Google Vision API. The langs parameter is a list of languages to look for during the OCR process. More information about the supported languages are described on this page

The parameter image could be:

• a string containing the path to the image file

• a numpy object (OpenCV)

• an Image object (Pillow/PIL)

It is possible to get some information about the Tesseract and Google Vision versions found in the system with get_tesseract_version() and get_google_vision_version() respectively.

The installation of the package also provides a command-line tool, please run

$ gpyocr --help

for more information.

Examples

Examples to read the text in the image tests/resources/european-test.png on this repository.

>>> import gpyocr
>>> gpyocr.tesseract_ocr('tests/resources/european-test.png')
('The (quick) [brown] {fox} ... ', 87.13636363636364)
>>> gpyocr.google_vision_ocr('tests/resources/european-test.png')
('The (quick) [brown] {fox} ... ', 98.00000190734863)
>>> import cv2 # support for OpenCV library
>>> gpyocr.tesseract_ocr(cv2.imread('tests/resources/european-test.png'))
('The (quick) [brown] {fox} ... ', 87.13636363636364)
>>> from PIL import Image # support for Pillow library
>>> gpyocr.tesseract_ocr(Image.open('tests/resources/european-test.png'))
('The (quick) [brown] {fox} ... ', 87.13636363636364)
>>> gpyocr.tesseract_ocr(
    'tests/resources/european-test.png'), lang='ita', psm=7,
    config='tessedit_char_whitelist=abc'
)
('bc aa cb  b c a ... ', 18.5)
>>> gpyocr.google_vision_ocr(
    'tests/resources/european-test.png', langs=['en, 'it']
)
('The (quick) [brown] {fox} ... ', 87.13636363636364)

Please see the unit tests for more examples.

Installation

Gpyocr is a pip package. To install it in your Python environment run:

$ pip install gpyocr

If you want to run Tesseract with gpyocr you have to install it in your system. In order to get the confidence value, gpyocr needs Tesseract >= 3.05. You could install Tesseract with the bash script tesseract_installer.sh that you find in the repository. If you want Tesseract 3.05 (the stable version) then run:

$ sudo ./tesseract_installer.sh 3.05

If you want to try Tesseract 4.00 (it’s still in beta) then run:

$ sudo ./tesseract_installer.sh 4.00

Note: this bash script is tested in Ubuntu 18.04 and CentOS 7; if you don’t have these systems, there may be problems installing some dependencies

To use Google Cloud Vision API, you have to authenticate with

$ export GOOGLE_APPLICATION_CREDENTIALS=/path/to/your-project-credentials.json

Please refer to their documentation for more information about installing and using Google Vision services.

License

Apache 2.0

How to contribute

This project is developed to be used by a specific application, so it is not very versatile. If you wish to have new features or if you have any kind of problems, please feel free to contact me via e-mail or open an issue here on GitHub.