You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
108 lines
3.3 KiB
Python
108 lines
3.3 KiB
Python
from __future__ import division, print_function
|
|
|
|
from warnings import warn
|
|
|
|
from lxml import etree as ET
|
|
import sys
|
|
|
|
from lxml.etree import XMLSyntaxError
|
|
|
|
|
|
def alto_namespace(tree):
|
|
"""Return the ALTO namespace used in the given ElementTree.
|
|
|
|
This relies on the assumption that, in any given ALTO file, the root element has the local name "alto". We do not
|
|
check if the files uses any valid ALTO namespace.
|
|
"""
|
|
root_name = ET.QName(tree.getroot().tag)
|
|
if root_name.localname == 'alto':
|
|
return root_name.namespace
|
|
else:
|
|
raise ValueError('Not an ALTO tree')
|
|
|
|
|
|
def alto_text(tree):
|
|
"""Extract text from the given ALTO ElementTree."""
|
|
|
|
nsmap = {'alto': alto_namespace(tree)}
|
|
|
|
lines = (
|
|
' '.join(string.attrib.get('CONTENT') for string in line.iterfind('alto:String', namespaces=nsmap))
|
|
for line in tree.iterfind('.//alto:TextLine', namespaces=nsmap))
|
|
text_ = '\n'.join(lines)
|
|
|
|
return text_
|
|
|
|
|
|
def page_namespace(tree):
|
|
"""Return the PAGE content namespace used in the given ElementTree.
|
|
|
|
This relies on the assumption that, in any given PAGE content file, the root element has the local name "PcGts". We
|
|
do not check if the files uses any valid PAGE namespace.
|
|
"""
|
|
root_name = ET.QName(tree.getroot().tag)
|
|
if root_name.localname == 'PcGts':
|
|
return root_name.namespace
|
|
else:
|
|
raise ValueError('Not a PAGE tree')
|
|
|
|
|
|
def page_text(tree):
|
|
"""Extract text from the given PAGE content ElementTree."""
|
|
|
|
nsmap = {'page': page_namespace(tree)}
|
|
|
|
def region_text(region):
|
|
try:
|
|
return region.find('./page:TextEquiv/page:Unicode', namespaces=nsmap).text
|
|
except AttributeError:
|
|
return None
|
|
|
|
region_texts = []
|
|
reading_order = tree.find('.//page:ReadingOrder', namespaces=nsmap)
|
|
if reading_order is not None:
|
|
for group in reading_order.iterfind('./*', namespaces=nsmap):
|
|
if ET.QName(group.tag).localname == 'OrderedGroup':
|
|
region_ref_indexeds = group.findall('./page:RegionRefIndexed', namespaces=nsmap)
|
|
for region_ref_indexed in sorted(region_ref_indexeds, key=lambda r: int(r.attrib['index'])):
|
|
region_id = region_ref_indexed.attrib['regionRef']
|
|
region = tree.find('.//page:TextRegion[@id="%s"]' % region_id, namespaces=nsmap)
|
|
if region is not None:
|
|
region_texts.append(region_text(region))
|
|
else:
|
|
warn('Not a TextRegion: "%s"' % region_id)
|
|
else:
|
|
raise NotImplementedError
|
|
else:
|
|
for region in tree.iterfind('.//page:TextRegion', namespaces=nsmap):
|
|
region_texts.append(region_text(region))
|
|
|
|
# XXX Does a file have to have regions etc.? region vs lines etc.
|
|
# Filter empty region texts
|
|
region_texts = (t for t in region_texts if t)
|
|
|
|
text_ = '\n'.join(region_texts)
|
|
|
|
return text_
|
|
|
|
|
|
def text(filename):
|
|
"""Read the text from the given file.
|
|
|
|
Supports PAGE, ALTO and falls back to plain text.
|
|
"""
|
|
|
|
try:
|
|
tree = ET.parse(filename)
|
|
except XMLSyntaxError:
|
|
with open(filename, 'r') as f:
|
|
return f.read()
|
|
try:
|
|
return page_text(tree)
|
|
except ValueError:
|
|
return alto_text(tree)
|
|
|
|
|
|
if __name__ == '__main__':
|
|
print(text(sys.argv[1]))
|