def extract_image_data(data, languages=None):
"""Extract text from a binary string of data."""
if TESSDATA_PREFIX is None:
raise ValueError("Env TESSDATA_PREFIX is not set, OCR will not work.")
key, text = get_cache(data)
if text is not None:
return text
try:
img = Image.open(StringIO(data))
except Exception as ex:
log.debug("Failed to parse image internally: %r", ex)
return ""
# TODO: play with contrast and sharpening the images.
try:
languages = _get_languages(languages)
extractor = Tesseract(TESSDATA_PREFIX, lang=languages)
extractor.set_page_seg_mode(PageSegMode.PSM_AUTO_OSD)
text = extractor.ocr_image(img)
log.debug("OCR done: %s, %s characters extracted", languages, len(text))
set_cache(key, text)
return text
except Exception as ex:
log.exception(ex)
return ""
def extract_image_data(data, languages=None):
"""Extract text from a binary string of data."""
if TESSDATA_PREFIX is None:
raise ValueError('Env TESSDATA_PREFIX is not set, OCR will not work.')
key, text = get_cache(data)
if text is not None:
return text
try:
img = Image.open(StringIO(data))
except Exception as ex:
log.debug('Failed to parse image internally: %r', ex)
return ''
# TODO: play with contrast and sharpening the images.
try:
languages = _get_languages(languages)
extractor = Tesseract(TESSDATA_PREFIX, lang=languages)
extractor.set_page_seg_mode(PageSegMode.PSM_AUTO_OSD)
text = extractor.ocr_image(img)
log.debug('OCR done: %s, %s characters extracted', languages,
len(text))
set_cache(key, text)
return text
except Exception as ex:
log.exception(ex)
return ''
def extract_image_data(data, languages=None):
""" Extract text from a binary string of data containing an image in
a commonly-used format. """
if TESSDATA_PREFIX is None:
raise ValueError('Env TESSDATA_PREFIX is not set, OCR will not work.')
key, text = get_cache(data)
if text is not None:
return text
img = Image.open(StringIO(data))
# TODO: play with contrast and sharpening the images.
try:
extractor = _get_tesseract()
extractor.set_image(img)
text = extractor.get_utf8_text()
extractor.clear()
set_cache(key, text)
return text
except Exception as ex:
log.exception(ex)
set_cache(key, '')
return ''
def crawl_file(file_path):
global processed
_, ext = os.path.splitext(file_path)
ext = ext.strip().lower()
if ext.lower() not in FILE_EXTENSIONS:
return
with open(file_path, 'rb') as fh:
data = fh.read()
key, text = get_cache(data)
if text is not None:
return
text = extract_image_data(data)
counter_lock.acquire()
try:
processed += 1
time_taken = time.time() - START_TIME
img_per_sec = time_taken / processed
finally:
counter_lock.release()
log.info('Extracted: %s (%d characters of text), %.3fs/img', file_path,
len(text), img_per_sec)
