forked from mgedmin/pdf2html
-
Notifications
You must be signed in to change notification settings - Fork 0
/
pdf2html.py
executable file
·650 lines (563 loc) · 24.4 KB
/
pdf2html.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
#!/usr/bin/python
# -*- coding: UTF-8 -*-
"""
Converts PDF to HTML e-books.
Relies on pdftohtml (http://pdftohtml.sourceforge.net/). Requires Python 2.5
or later.
Method of operation:
1. Run pdftohtml -xml on the PDF file
2. Process the XML file, detect paragraph boundaries by paying careful
attention to first-line indents
3. Produce an HTML
The HTML produced differs from the one you'd get from pdftohtml in these ways:
* Paragraphs are preserved; line breaks inside paragraphs are lost.
* Multiple adjacent spaces are left as spaces, not converted to a run of
* Page boundaries are discarded, not rendered as <hr>
* The HTML produced is modern XHTML, not ancient HTML 3 with an explicit
dark-grey bgcolor on the <BODY>.
Bugs:
* doesn't handle superscript well
* doesn't handle small caps
* loses information such as fonts and colours
Config file:
Put a .pdf2htmlrc in the same directory as the source PDF file. Every
section, denoted [pattern] can apply options to files matching the
pattern, e.g.
[hello.pdf]
header_pos = 166
[*.pdf]
footer_pos = -1
All options you can specify on the command line can be specified
in the config file (with the obvious exceptions of --version and --help).
Currently the most useful options you can specify this way are header and
footer positions if you want to suppres header/footer text from the output.
The position is specified in points, with 0 at the top of the page,
increasing downwards. All text above the header pos as well as all text
below the footer pos is discarded. Specify -1 (which is the default) to
disable. To find out the right values, use --keep and take a look at
text coordinates in the intermediate .xml file.
Bugs:
There are no tests.
To disable header_pos/footer_pos it would make sense to use 'off', not -1.
I may want to use negative numbers to specify positions relative to the
bottom of the page.
Copyright (c) 2009-2011 Marius Gedminas <[email protected]>.
Licenced under the GNU GPL.
"""
import optparse
import os
import shutil
import subprocess
import sys
import tempfile
import ConfigParser
import fnmatch
import re
from collections import defaultdict
from xml.etree import cElementTree as ET
__version__ = '0.7dev'
__author__ = 'Marius Gedminas'
class Error(Exception):
pass
class NotFound(object):
def __repr__(self):
return 'NotFound'
class Options(object):
"""Conversion options"""
_defs = [
('debug', bool),
('keep', bool),
('title', str),
('subtitle', str),
('header_pos', int),
('footer_pos', int),
('leading', int),
('indent', int),
('left_margin', int),
('horiz_leeway', int),
('skip_initial_pages', int),
('skip_generator', bool),
('encoding', str),
]
_help = dict(
debug='print verbose diagnostics',
keep='keep temporary files',
header_pos='suppress text above this point (header)',
footer_pos='suppress text below this point (footer)',
leading='override autodetected intra-paragraph leading',
left_margin='override autodetected left margin',
horiz_leeway='override autodetected horizontal leeway',
indent='override autodetected indent',
title='document title',
subtitle='document subtitle',
skip_initial_pages='skip the first N pages of output',
skip_generator='skip <meta name="generator" ...>',
encoding='character set for the HTML',
)
_defaults = dict(
encoding='UTF-8',
)
def __init__(self):
for name, type in self._defs:
setattr(self, name, self._defaults.get(name))
def add_to_option_parser(self, parser):
for name, type in self._defs:
optname = name.replace('_', '-')
if type is bool:
parser.add_option('--' + optname, action='store_true',
help=self._help[name])
parser.add_option('--no-' + optname, action='store_false',
dest=name, help=optparse.SUPPRESS_HELP)
else:
parser.add_option('--' + optname, type=type,
help=self._help[name],
default=self._defaults.get(name))
def update_from_config_section(self, cp, section):
getters = {bool: cp.getboolean,
int: cp.getint,
str: cp.get}
for name, type in self._defs:
if cp.has_option(section, name):
value = getters[type](section, name)
setattr(self, name, value)
def update_from_optparse(self, opts):
for name, type in self._defs:
value = getattr(opts, name, None)
if value is not None:
setattr(self, name, value)
def parse_config_file(options, config_file, filename_to_match='*'):
cp = ConfigParser.SafeConfigParser()
cp.read([config_file])
for s in cp.sections():
if fnmatch.fnmatch(filename_to_match, s):
if options.debug:
print "Applying [%s] from %s" % (s, config_file)
options.update_from_config_section(cp, s)
def convert_pdf_to_html(pdf_file, html_file, opts=None):
tmpdir = tempfile.mkdtemp(prefix='pdf2html-')
try:
xml_file = os.path.join(tmpdir, 'data') # pdf2html always adds .xml
subprocess.check_call(['pdftohtml', '-hidden', '-nodrm', '-xml',
pdf_file, xml_file])
xml_file += '.xml'
convert_pdfxml_to_html(xml_file, html_file, opts)
finally:
if opts and opts.keep:
print "Temporary files kept in %s" % tmpdir
else:
shutil.rmtree(tmpdir)
def convert_pdfxml_to_html(xml_file, html_file, opts=None):
debug = False
if opts:
debug = opts.debug
# The structure of the pdf2xml documents is this:
# <pdf2xml>
# <page number="1" position="absolute" top="0" left="0"
# height="800" width="600" >
# <fontspec id="0" size="12" family="Times" color="#000000" />
# ...
# <text top="100" left="60" width="200" height="13"
# font="0"><i><b>Some text</b></i></text>
# ...
# </page>
# ...
# </pdf2xml>
# Notes:
# * The scope of <fontspecs> is larger than a single page
# * Coordinates are typical screen coordinates: i.e. (0, 0) is top-left
# and y increases downwards
tree = ET.parse(xml_file)
root_tag = tree.getroot().tag
if root_tag != 'pdf2xml':
raise Error('Expected a pdf2xml document, got %s' % root_tag)
html = ET.Element('html')
html.text = html.tail = '\n'
head = ET.SubElement(html, 'head')
head.text = head.tail = '\n'
charset = ET.SubElement(head, 'meta',
{'http-equiv': 'content-type',
'content': 'text/html; charset=UTF-8'})
charset.tail = '\n'
if opts and not opts.skip_generator:
generator = ET.SubElement(head, 'meta',
name='generator',
content='pdf2html %s by %s' % (__version__,
__author__))
generator.tail = '\n'
title = ET.SubElement(head, 'title')
if opts and opts.title:
title.text = opts.title
else:
title.text = os.path.basename(html_file)
title.tail = '\n'
body = ET.SubElement(html, 'body')
body.text = body.tail = '\n'
if opts.title:
h1 = ET.SubElement(body, 'h1')
h1.text = opts.title
h1.tail = '\n'
if opts.subtitle:
h2 = ET.SubElement(body, 'h2')
h2.text = opts.subtitle
h2.tail = '\n'
class Font(object):
def __init__(self, size, family, color):
self.size = size
self.family = family
self.color = color
def __hash__(self):
return hash(self.size, self.family, self.color)
def __eq__(self, other):
return type(other) == type(self) and (self.size, self.family,
self.color) == (other.size,
other.family, other.color)
def __ne__(self, other):
return not self.__eq__(other)
fonts = {}
for page in tree.findall('page'):
for fontspec in page.findall('fontspec'):
font = Font(fontspec.get('size'), fontspec.get('family'),
fontspec.get('color'))
fonts[fontspec.get('id')] = font
def iter_attrs(attr, pagefilter=None):
for page in tree.findall('page'):
if pagefilter and not pagefilter(page):
continue
if attr == 'leading':
prev = None
for chunk in page.findall('text'):
if prev is not None:
yield int(chunk.get('top')) - int(prev.get('top'))
prev = chunk
else:
for chunk in page.findall('text'):
yield chunk.get(attr)
def count_frequencies(attr, pagefilter=None):
frequencies = defaultdict(int)
for value in iter_attrs(attr, pagefilter):
frequencies[value] += 1
return frequencies
def n_smallest(attr, n, pagefilter=None, extratitle=''):
frequencies = count_frequencies(attr, pagefilter)
frequencies = [(int(v), f) for (v, f) in frequencies.items()]
frequencies.sort()
if debug:
if not extratitle and pagefilter and pagefilter.__doc__:
extratitle = " (%s)" % pagefilter.__doc__.strip()
print "Top 5 smallest values of %r:%s" % (attr, extratitle)
max_f = max(1, max(freq for (value, freq) in frequencies))
for v, f in frequencies[:5]:
bar = '*' * (30 * f / max_f)
print ' %6d chunks have value %-6s %s' % (f, v, bar)
return [value for (value, freq) in frequencies[:n]]
def n_largest(attr, n, pagefilter=None, extratitle=''):
frequencies = count_frequencies(attr, pagefilter)
frequencies = [(int(v), f) for (v, f) in frequencies.items()]
frequencies.sort()
if debug:
if not extratitle and pagefilter and pagefilter.__doc__:
extratitle = " (%s)" % pagefilter.__doc__.strip()
print "Top 5 largest values of %r:%s" % (attr, extratitle)
max_f = max(1, max(freq for (value, freq) in frequencies))
for v, f in frequencies[-5:]:
bar = '*' * (30 * f / max_f)
print ' %6d chunks have value %-6s %s' % (f, v, bar)
return [value for (value, freq) in frequencies[-n:]]
def n_most_frequent(attr, n, pagefilter=None, extratitle=''):
frequencies = count_frequencies(attr, pagefilter)
frequencies = [(freq, value) for value, freq in frequencies.items()]
frequencies.sort()
if debug:
if not extratitle and pagefilter and pagefilter.__doc__:
extratitle = " (%s)" % pagefilter.__doc__.strip()
print "Top 5 most frequent values of %r:%s" % (attr, extratitle)
for f, v in frequencies[-5:]:
bar = '*' * (30 * f / frequencies[-1][0])
print ' %6d chunks have value %-6s %s' % (f, v, bar)
return [value for (freq, value) in frequencies[-n:]]
def most_frequent(attr):
values = n_most_frequent(attr, 1)
if values:
return values[0]
else:
return NotFound() # something not equal to anything else
def margin_and_indent(pagefilter=None):
xs = sorted(map(int, n_most_frequent('left', 2, pagefilter)))
if len(xs) == 2:
return xs
elif len(xs) == 1:
# NotFound() is something not equal to anything else
return xs[0], NotFound()
else:
# NotFound() is something not equal to anything else
return NotFound(), NotFound()
def odd_pages(page):
"odd pages"
return int(page.get('number')) % 2 == 1
def even_pages(page):
"even pages"
return int(page.get('number')) % 2 == 0
most_frequent_leading = most_frequent('leading')
# lots of short paragraphs break this heuristic
most_frequent_height = most_frequent('height')
most_frequent_font = fonts.get(most_frequent('font'))
# XXX sometimes you have more than one fontspec with the same
# attributes (family, size, color), this might skew the frequency
# distribution somewhat
# XXX could crash if there are no text chunks or all of them are at the
# same x position
odd_left, odd_indent = margin_and_indent(odd_pages)
even_left, even_indent = margin_and_indent(even_pages)
if isinstance(even_left, NotFound) or isinstance(odd_left, NotFound):
horiz_leeway = 0
else:
horiz_leeway = abs(even_left - odd_left)
leading_leeway = 1 # sometimes superscripts increase the leading of some
# lines inside a paragraph; no idea how to estimate this
# yet
# XXX: could crash if there are no text chunks at all
if debug:
try:
max_text_width = max(int(w) for w in iter_attrs('width'))
except ValueError: # max() arg is an empty sequence
max_text_width = 0
print "Widest text chunk = %d" % max_text_width
try:
text_width = max(map(int, n_most_frequent('width', 3)))
except ValueError: # max() arg is an empty sequence
text_width = 0
if debug:
print "Guessing paragraph width = %d" % text_width
text_width = text_width * 8 / 10
# try to autodetect headers/footers?
maybe_header = n_smallest('top', 1)[0]
maybe_footer = n_largest('top', 1)[0]
# XXX: how do I validate these? ohwell, at least --debug will show
if debug:
print "Guessing left margin = %s (odd pages), %s (even pages)" % (odd_left, even_left)
print "Guessing indent = %s (odd pages), %s (even pages)" % (odd_indent, even_indent)
print "Guessing horizontal leeway = %s" % (horiz_leeway)
print "Guessing minimum paragraph line width = %s" % text_width
print "Guessing leading = %s" % (most_frequent_leading)
if opts and opts.left_margin and opts.left_margin >= 0:
odd_left = even_left = opts.left_margin
if opts.debug:
print "Overriding left margin = %d" % opts.left_margin
if opts and opts.horiz_leeway and opts.horiz_leeway >= 0:
horiz_leeway = opts.horiz_leeway
if opts.debug:
print "Overriding horizontal leeway = %d" % horiz_leeway
if opts and opts.indent and opts.indent >= 0:
odd_indent = even_indent = opts.indent
if opts.debug:
print "Overriding indent = %d" % opts.indent
if odd_indent == odd_left:
odd_indent = -1
if opts.debug:
print "Disabling indent for odd pages, since same as left margin"
if even_indent == even_left:
even_indent = -1
if opts.debug:
print "Disabling indent for even pages, since same as left margin"
if opts and opts.leading and opts.leading > 0:
most_frequent_leading = opts.leading
if opts.debug:
print "Overriding leading = %d" % most_frequent_leading
header_pos = None
if opts and opts.header_pos and opts.header_pos != -1:
header_pos = opts.header_pos
if opts.debug:
print "Suppressing header text above %d" % header_pos
footer_pos = None
if opts and opts.footer_pos and opts.header_pos != -1:
footer_pos = opts.footer_pos
if opts.debug:
print "Suppressing footer text below %d" % footer_pos
def looks_like_a_heading(chunk):
if len(chunk) != 1:
bold = None
else:
bold = chunk
while bold.tag != 'b':
if len(bold) != 1:
bold = None
break
bold = bold[0]
if bold:
return (fonts[chunk.get('font')] != most_frequent_font
and int(chunk.get('height')) >= int(most_frequent_height)
and bold.text
and any(c.isalpha() for c in bold.text))
else:
return (fonts[chunk.get('font')] != most_frequent_font
and int(chunk.get('height')) > int(most_frequent_height)
and chunk.text
and all(c.isdigit() for c in chunk.text))
def drop_cap(prev_chunk, chunk):
if not prev_chunk.text or not chunk.text:
return False
if not 1 <= len(prev_chunk.text) <= 2:
return False
if int(prev_chunk.get('height')) <= int(chunk.get('height')):
return False
drop_cap_horiz_gap = int(prev_chunk.get('width')) / 2
drop_cap_vert_gap = int(prev_chunk.get('height')) / 4
if abs(int(prev_chunk.get('left')) + int(prev_chunk.get('width')) - int(chunk.get('left'))) > drop_cap_horiz_gap:
return False
return (abs(int(prev_chunk.get('top')) - int(chunk.get('top'))) > drop_cap_vert_gap or
abs(int(prev_chunk.get('top')) + int(prev_chunk.get('height'))
- int(chunk.get('top')) - int(chunk.get('height'))) > drop_cap_vert_gap)
para = None
prev_chunk = None
prev_was_superscript = False
for page in tree.findall('page'):
if odd_pages(page):
indent = odd_indent
left_margin = odd_left
else:
indent = even_indent
left_margin = even_left
for chunk in page.findall('text'):
suppress = False
start_superscript = False
if opts and opts.skip_initial_pages and int(page.get('number')) <= opts.skip_initial_pages:
suppress = True
suppress_reason = 'INITIAL PAGES'
elif header_pos and int(chunk.get('top')) <= header_pos:
suppress = True
suppress_reason = 'HEADER'
elif footer_pos and int(chunk.get('top')) >= footer_pos:
suppress = True
suppress_reason = 'FOOTER'
if prev_chunk is None or suppress:
continues_paragraph = False
else:
leading = int(chunk.get('top')) - int(prev_chunk.get('top'))
start_superscript = end_superscript = False
if leading < most_frequent_leading and int(chunk.get('height')) < int(prev_chunk.get('height')):
# superscript
start_superscript = True
elif leading < 0 and int(chunk.get('height')) > int(prev_chunk.get('height')) and prev_was_superscript:
# end superscript!
end_superscript = True
continues_paragraph = start_superscript or end_superscript or (
int(chunk.get('left')) != indent and
int(chunk.get('left')) <= int(prev_chunk.get('left')) + horiz_leeway and
(int(prev_chunk.get('left')) + int(prev_chunk.get('width')) >= left_margin + horiz_leeway + text_width) and
leading <= most_frequent_leading + leading_leeway and
fonts[chunk.get('font')] == fonts[prev_chunk.get('font')]
) or (
chunk.get('top') == prev_chunk.get('top')
) or drop_cap(prev_chunk, chunk)
if debug and chunk.get('assert_continues') and not continues_paragraph:
print "*** DEBUG assertion failed"
print ' ', ET.tostring(prev_chunk).rstrip()
print ' ', ET.tostring(chunk).rstrip()
print "tops match?", chunk.get('top') == prev_chunk.get('top')
print "OR drop cap:", drop_cap(prev_chunk, chunk)
print "OR not indent:", int(chunk.get('left')) != indent
print "AND same or to the left:", int(chunk.get('left')) <= int(prev_chunk.get('left')) + horiz_leeway
print "AND prev chunk wide enough:", int(prev_chunk.get('width')) >= text_width
print "AND same font:", fonts[chunk.get('font')] == fonts[prev_chunk.get('font')]
print "AND close enough vertically:", leading <= most_frequent_leading + leading_leeway
if para is not None and continues_paragraph:
# join with previous
if chunk.text is None:
chunk.text = ''
if start_superscript:
sup = ET.Element('sup')
sup.text = chunk.text
sup[:] = chunk[:]
sup.tail = para.tail
para.tail = None
para.append(sup)
else:
if drop_cap(prev_chunk, chunk) or end_superscript:
joiner = ''
else:
joiner = '\n'
if len(para):
if para[-1].tail:
para[-1].tail += joiner + chunk.text
else:
para[-1].tail = joiner + chunk.text
else:
if para.text:
para.text += joiner + chunk.text
else:
para.text = chunk.text
para[len(para):] = chunk[:]
else:
# start new paragraph
if looks_like_a_heading(chunk):
new_para = ET.Element('h2')
else:
new_para = ET.Element('p')
new_para.text = chunk.text
new_para[:] = chunk[:]
new_para.tail = '\n'
if suppress:
# I hate ElementTree: it escapes < and > inside comments.
# This should be fixed in Python 2.7:
# http://bugs.python.org/issue2746
comment = ET.Comment('%s: %s' % (suppress_reason, ET.tostring(new_para).strip()))
comment.tail = '\n'
body.append(comment)
else:
para = new_para
body.append(para)
if not suppress:
prev_chunk = chunk
prev_was_superscript = start_superscript
def postprocess(s):
s = re.sub(ur'-\n([a-ząčęėįšųūž&])', r'\1', s)
s = s.replace(u'\uFB00', 'ff')
s = s.replace(u'\uFB01', 'fi')
s = s.replace(u'\uFB02', 'fl')
s = s.replace(u'\uFB03', 'ffi')
s = s.replace(u'\uFB04', 'ffl')
return s
for item in html.getiterator():
if item.text:
item.text = postprocess(item.text)
if item.tail:
item.tail = postprocess(item.tail)
with file(html_file, 'wb') as f:
f.write(ET.tostring(html, encoding=opts.encoding))
def main():
options = Options()
parser = optparse.OptionParser(usage='%prog input.pdf [output.html]')
parser.add_option('--version', action='store_true',
help='print version and exit')
options.add_to_option_parser(parser)
opts, args = parser.parse_args()
if opts.version:
print "pdf2html.py v%s by %s" % (__version__, __author__)
return
if len(args) < 1:
parser.error('please specify an input file name')
if len(args) > 2:
parser.error('too many arguments')
pdf_name = args[0]
if len(args) > 1:
output_name = args[1]
else:
output_name = os.path.splitext(pdf_name)[0] + '.html'
# special_case, since parse_config_file wants this defined early
options.debug = opts.debug
config_name = os.path.join(os.path.dirname(pdf_name), '.pdf2htmlrc')
parse_config_file(options, config_name, os.path.basename(pdf_name))
# command-line options override those set in the config file
options.update_from_optparse(opts)
if os.path.exists(output_name):
sys.exit('cowardly refusing to overwrite %s' % output_name)
try:
if os.path.splitext(pdf_name)[1] == '.xml':
convert_pdfxml_to_html(pdf_name, output_name, options)
else:
convert_pdf_to_html(pdf_name, output_name, options)
except Error, e:
sys.exit(str(e))
if __name__ == '__main__':
main()