Files
pdfplumber/pdfplumber/utils.py
T
2016-03-07 23:06:08 -05:00

304 lines
8.7 KiB
Python

from pdfminer.utils import PDFDocEncoding
from decimal import Decimal, ROUND_HALF_UP
from operator import itemgetter
import itertools
import six
def cluster_list(xs, tolerance=0):
tolerance = decimalize(tolerance)
if tolerance == 0: return [ [x] for x in sorted(xs) ]
if len(xs) < 2: return [ [x] for x in sorted(xs) ]
groups = []
xs = list(sorted(xs))
current_group = [xs[0]]
last = xs[0]
for x in xs[1:]:
if x <= (last + tolerance):
current_group.append(x)
else:
groups.append(current_group)
current_group = [x]
last = x
groups.append(current_group)
return groups
def make_cluster_dict(values, tolerance):
tolerance = decimalize(tolerance)
clusters = cluster_list(set(values), tolerance)
nested_tuples = [ [ (val, i) for val in value_cluster ]
for i, value_cluster in enumerate(clusters) ]
cluster_dict = dict(itertools.chain(*nested_tuples))
return cluster_dict
def decode_text(s):
"""
Decodes a PDFDocEncoding string to Unicode.
Adds py3 compatability to pdfminer's version.
"""
if s.startswith(b'\xfe\xff'):
return six.text_type(s[2:], 'utf-16be', 'ignore')
else:
ords = (ord(c) if type(c) == str else c for c in s)
return ''.join(PDFDocEncoding[o] for o in ords)
def decimalize(v, q=None):
if type(v) == int: return Decimal(v)
if type(v) == float:
if q != None:
return Decimal(repr(v)).quantize(Decimal(repr(q)),
rounding=ROUND_HALF_UP)
else:
return Decimal(repr(v))
return v
def is_dataframe(collection):
cls = collection.__class__
name = ".".join([ cls.__module__, cls.__name__ ])
return name == "pandas.core.frame.DataFrame"
def to_list(collection):
if is_dataframe(collection):
return collection.to_dict("records")
else:
return collection
def collate_line(line_chars, tolerance=0):
tolerance = decimalize(tolerance)
coll = ""
last_x1 = None
for char in sorted(line_chars, key=itemgetter("x0")):
if last_x1 != None and char["x0"] > (last_x1 + tolerance):
coll += " "
last_x1 = char["x1"]
coll += char["text"]
return coll
def get_bbox(objs):
return (
min(map(itemgetter("x0"), objs)),
min(map(itemgetter("top"), objs)),
max(map(itemgetter("x1"), objs)),
max(map(itemgetter("bottom"), objs)),
)
def extract_words(chars, x_tolerance=0, y_tolerance=0):
x_tolerance = decimalize(x_tolerance)
y_tolerance = decimalize(y_tolerance)
def process_word_chars(chars):
x0, top, x1, bottom = get_bbox(chars)
return {
"x0": x0,
"x1": x1,
"top": top,
"bottom": bottom,
"text": "".join(map(itemgetter("text"), chars))
}
def get_line_words(chars, tolerance=0):
chars_sorted = sorted(chars, key=itemgetter("x0"))
words = []
current_word = []
for char in chars_sorted:
if len(current_word) == 0:
current_word.append(char)
else:
last_char = current_word[-1]
if char["x0"] > (last_char["x1"] + tolerance):
words.append(current_word)
current_word = [ char ]
else:
current_word.append(char)
words.append(current_word)
processed_words = list(map(process_word_chars, words))
return processed_words
chars = to_list(chars)
doctops = map(itemgetter("doctop"), chars)
doctop_clusters = make_cluster_dict(doctops, y_tolerance)
with_cluster = ((char, doctop_clusters.get(char["doctop"]))
for char in chars)
get_0 = itemgetter(0)
get_1 = itemgetter(1)
with_cluster_sorted = sorted(with_cluster, key=get_1)
grouped = itertools.groupby(with_cluster_sorted, key=get_1)
nested = [ get_line_words(map(get_0, line_chars), tolerance=x_tolerance)
for k, line_chars in grouped ]
words = list(itertools.chain(*nested))
return words
def extract_text(chars, x_tolerance=0, y_tolerance=0):
if len(chars) == 0:
return None
get_0 = itemgetter(0)
get_1 = itemgetter(1)
chars = to_list(chars)
doctops = map(itemgetter("doctop"), chars)
doctop_clusters = make_cluster_dict(doctops, y_tolerance)
with_cluster = ((char, doctop_clusters.get(char["doctop"]))
for char in chars)
grouped = itertools.groupby(sorted(with_cluster, key=get_1), key=get_1)
lines = (collate_line(map(get_0, items), x_tolerance)
for k, items in grouped)
coll = "\n".join(lines)
return coll
collate_chars = extract_text
def find_gutters(chars, orientation, min_size=5):
"""
The size of a gutter is the distance between the beginning
of the current character and the beginning of the next character.
"""
if orientation not in ("h", "v"):
raise ValueError('`orientation` must be "h" or "v".')
if len(chars) == 0:
raise ValueError("No chars.")
start_prop = "x0" if orientation == "v" else "top"
end_prop = "x1" if orientation == "v" else "bottom"
get_start = itemgetter(start_prop)
get_end = itemgetter(end_prop)
starts = list(sorted(set(map(get_start, chars))))
end_max = max(map(get_end, chars))
start_gaps = ((p1, p2 - p1)
for p1, p2 in zip(starts, starts[1:]))
gutters = [ g[0] + g[1]/2
for g in start_gaps
if g[1] >= min_size ]
if starts[0] < gutters[0]:
gutters = [ starts[0] ] + gutters
if end_max > gutters[-1]:
gutters = gutters + [ end_max + Decimal('0.001') ]
return gutters
def point_inside_bbox(point, bbox):
px, py = point
bx0, by0, bx1, by1 = map(decimalize, bbox)
return (px >= bx0) and (px <= bx1) and (py >= by0) and (py <= by1)
def obj_inside_bbox_score(obj, bbox):
corners = (
(obj["x0"], obj["top"]),
(obj["x0"], obj["bottom"]),
(obj["x1"], obj["top"]),
(obj["x1"], obj["bottom"]),
)
score = sum(point_inside_bbox(c, bbox) for c in corners)
return score
def crop_obj(obj, bbox, score=None):
if score == None:
score = obj_inside_bbox_score(obj, bbox)
if score == 0: return None
if score == 4: return obj
x0, top, x1, bottom = map(decimalize, bbox)
copy = dict(obj)
x_changed = False
y_changed = False
if copy["x0"] < x0:
copy["x0"] = x0
x_changed = True
if copy["x1"] > x1:
copy["x1"] = x1
x_changed = True
if copy["top"] < top:
diff = top - copy["top"]
copy["top"] = top
copy["doctop"] = copy["doctop"] + diff
copy["y1"] = copy["y1"] - diff
y_changed = True
if copy["bottom"] > bottom:
diff = bottom - copy["bottom"]
copy["bottom"] = bottom
copy["y0"] = copy["y0"] + diff
y_changed = True
if x_changed:
copy["width"] = copy["x1"] - copy["x0"]
if y_changed:
copy["height"] = copy["bottom"] - copy["top"]
return copy
def within_bbox(objs, bbox, strict=True, crop=False):
"""
strict: Include only objects that are fully within the box?
crop: Crop lines and rectangles to the box?
"""
if isinstance(objs, dict):
return dict((k, within_bbox(v, bbox, strict=strict, crop=crop))
for k,v in objs.items())
initial_type = type(objs)
objs = to_list(objs)
scores = ((obj, obj_inside_bbox_score(obj, bbox)) for obj in objs)
if crop:
matching = [ (crop_obj(s[0], bbox, s[1]) if s[1] < 4 else s[0])
for s in scores if s[1] > 0 ]
elif strict:
matching = [ s[0] for s in scores if s[1] == 4 ]
else:
matching = [ s[0] for s in scores if s[1] > 0 ]
return initial_type(matching)
def dividers_to_bounds(dividers):
return list(zip(dividers, dividers[1:]))
def extract_table(chars, v, h,
x_tolerance=0,
y_tolerance=0):
initial_type = type(chars)
chars = to_list(chars)
v_bounds = dividers_to_bounds(v)
h_bounds = dividers_to_bounds(h)
table_arr = []
for hb in h_bounds:
test = lambda c: (c["top"] >= hb[0]) & (c["top"] < hb[1])
row = list(filter(test, chars))
row_arr = []
for vb in v_bounds:
test = lambda c: (c["x0"] >= vb[0]) & (c["x0"] < vb[1])
cell = list(filter(test, row))
if len(cell):
cell_value = collate_chars(cell,
x_tolerance=x_tolerance,
y_tolerance=y_tolerance).strip()
else:
cell_value = None
row_arr.append(cell_value)
table_arr.append(row_arr)
return initial_type(table_arr)