Files
mayan-edms/apps/ocr/api.py
2011-02-09 13:55:01 -04:00

67 lines
1.9 KiB
Python
Executable File

#Some code from http://wiki.github.com/hoffstaetter/python-tesseract
import os
import subprocess
import tempfile
from django.utils.translation import ugettext as _
from documents.models import DocumentPage
from documents.conf.settings import TEMPORARY_DIRECTORY
from converter.api import convert_document_for_ocr
from ocr.conf.settings import TESSERACT_PATH
def cleanup(filename):
''' tries to remove the given filename. Ignores non-existent files '''
try:
os.remove(filename)
except OSError:
pass
class TesseractError(Exception):
def __init__(self, status, message):
self.status = status
self.message = message
def run_tesseract(input_filename, output_filename_base, lang=None):
command = [TESSERACT_PATH, input_filename, output_filename_base]
if lang is not None:
command += ['-l', lang]
proc = subprocess.Popen(command, stderr=subprocess.PIPE)
return (proc.wait(), proc.stderr.read())
def ocr_document(document):
total_pages = 1
page = 0
while page < total_pages:
imagefile = convert_document_for_ocr(document, page=page)
desc, filepath = tempfile.mkstemp()
try:
status, error_string = run_tesseract(imagefile, filepath)
if status:
errors = get_errors(error_string)
raise TesseractError(status, errors)
finally:
ocr_output = os.extsep.join([filepath, 'txt'])
f = file(ocr_output)
try:
document_page, created = DocumentPage.objects.get_or_create(document=document,
page_number=page)
document_page.content = f.read().strip()
document_page.page_label = _(u'Text from OCR')
document_page.save()
finally:
f.close()
cleanup(filepath)
cleanup(ocr_output)
cleanup(imagefile)
page += 1