Python Language
Optische Zeichenerkennung

Einführung

PyTesseract

PyTesseract ist ein in der Entwicklung befindliches Python-Paket für OCR.

PyTesseract zu benutzen ist ziemlich einfach:

try:
    import Image
except ImportError:
    from PIL import Image

import pytesseract

    #Basic OCR
    print(pytesseract.image_to_string(Image.open('test.png')))

    #In French
    print(pytesseract.image_to_string(Image.open('test-european.jpg'), lang='fra’))

PyTesseract ist Open Source und kann hier gefunden werden .

PyOCR

Ein anderes Modul ist PyOCR , dessen Quellcode hier ist .

Auch einfach zu bedienen und bietet mehr Funktionen als PyTesseract .

Zu initialisieren:

from PIL import Image
import sys

import pyocr
import pyocr.builders

tools = pyocr.get_available_tools()
# The tools are returned in the recommended order of usage
tool = tools[0]

langs = tool.get_available_languages()
lang = langs[0]
# Note that languages are NOT sorted in any way. Please refer
# to the system locale settings for the default language
# to use.

Und einige Anwendungsbeispiele:

txt = tool.image_to_string(
    Image.open('test.png'),
    lang=lang,
    builder=pyocr.builders.TextBuilder()
)
# txt is a Python string

word_boxes = tool.image_to_string(
    Image.open('test.png'),
    lang="eng",
    builder=pyocr.builders.WordBoxBuilder()
)
# list of box objects. For each box object:
#   box.content is the word in the box
#   box.position is its position on the page (in pixels)
#
# Beware that some OCR tools (Tesseract for instance)
# may return empty boxes

line_and_word_boxes = tool.image_to_string(
    Image.open('test.png'), lang="fra",
    builder=pyocr.builders.LineBoxBuilder()
)
# list of line objects. For each line object:
#   line.word_boxes is a list of word boxes (the individual words in the line)
#   line.content is the whole text of the line
#   line.position is the position of the whole line on the page (in pixels)
#
# Beware that some OCR tools (Tesseract for instance)
# may return empty boxes

# Digits - Only Tesseract (not 'libtesseract' yet !)
digits = tool.image_to_string(
    Image.open('test-digits.png'),
    lang=lang,
    builder=pyocr.tesseract.DigitBuilder()
)
# digits is a python string