camelot-py/camelot/parsers/base.py

96 lines
2.5 KiB
Python

# -*- coding: utf-8 -*-
import os
from ..utils import (
get_page_layout,
get_text_objects
)
from ..core import Table
from ..image_processing import (
adaptive_threshold,
find_lines,
find_contours,
find_joints
)
# Pylint can't detect contents of cv2
from cv2 import imread # pylint: disable=no-name-in-module
class BaseParser(object):
"""Defines a base parser.
"""
def __init__(self, parser_id):
self.imagename = None
self.pdf_image = None
self.id = parser_id
# For plotting details of parsing algorithms
self.debug_info = {}
def _generate_layout(self, filename, page_idx, layout_kwargs):
self.filename = filename
self.layout_kwargs = layout_kwargs
self.layout, self.dimensions = get_page_layout(
filename,
**layout_kwargs
)
self.images = get_text_objects(self.layout, ltype="image")
self.horizontal_text = get_text_objects(
self.layout,
ltype="horizontal_text"
)
self.vertical_text = get_text_objects(
self.layout,
ltype="vertical_text"
)
self.pdf_width, self.pdf_height = self.dimensions
self.rootname, __ = os.path.splitext(self.filename)
self.page = page_idx
def generate_image(self):
if self.pdf_image is None:
self._generate_image_file()
self.pdf_image = imread(self.imagename)
def _generate_image_file(self):
if self.imagename:
return
from ..ext.ghostscript import Ghostscript
self.imagename = "".join([self.rootname, ".png"])
gs_call = "-q -sDEVICE=png16m -o {} -r300 {}".format(
self.imagename, self.filename
)
gs_call = gs_call.encode().split()
null = open(os.devnull, "wb")
Ghostscript(*gs_call, stdout=null)
# with Ghostscript(*gs_call, stdout=null) as gs:
# pass
null.close()
"""Initialize new table object, ready to be populated
Parameters
----------
table_idx : int
Index of this table within the pdf page analyzed
cols : list
list of coordinate boundaries tuples (left, right)
rows : list
list of coordinate boundaries tuples (bottom, top)
Returns
-------
t : camelot.core.Table
"""
def _initialize_new_table(self, table_idx, cols, rows):
table = Table(cols, rows)
table.page = self.page
table.order = table_idx + 1
return table