I am trying to extract sections of a PDF file, for use in text analysis. I tried using pdfextract to accomplish this. However, a command such as
pdf-extract extract --regions --no-lines Bauer2010.pdf
only extract the (x,y) coordinates of a region, as in the example below.
<region x="226.32" y="750.47" width="165.57" height="6.37"
line_height="6.37" font="BGBFHO+AdvP4DF60E">Patient Education and
Counseling 79 (2010) 315-319</region>
Can sections of a PDF be extracted?
Have a look at http://text-analyzer.com where you can upload your PDF file and it will convert it into a format suitable for Natural Language Processing. Once converted into a text file it can then process the file, breaking it down into sentences with sentiment analysis. It has over 40 different types of sentence views where you can tag sections. Those tagged sentences can be exported.
Related
I'm trying to extract text from Arabic pdfs - raw data extraction not OCR -.
I tried many packages, tools and none of them worked, python packages, pdfBox, adobe API, and many other tools and all of them field to extract the text correctly, either it reads the text LTR or it do wrong decoding.
Here is a two sample from different tools
sample 1:
املحتويات
7 الثانية الطبعة مقدمة
9 وتاريخه األدب -١
51 الجاهليون -٢
95 الشعر نحل أسباب -٣
149 والشعراء الشعر -٤
213 مرض شعر -٥
271 الشعر -٦
285 الجاهيل النثر -٧
sample 2:
ﺔﻴﻧﺎﺜﻟا ﺔﻌﺒﻄﻟا ﺔﻣﺪﻘﻣ
ﻪﺨﻳرﺎﺗو بدﻷا -١
نﻮﻴﻠﻫﺎﺠﻟا -٢
ﺮﻌﺸﻟا ﻞﺤﻧ بﺎﺒﺳأ -٣
ءاﺮﻌﺸﻟاو ﺮﻌﺸﻟا -٤
ﴬﻣ ﺮﻌﺷ -٥
ﺮﻌﺸﻟا -٦
ﲇﻫﺎﺠﻟا ﺮﺜﻨﻟا -٧
original text
and yes I can copy it and get the same rendered text.
are there any tool that can extract Arabic text correctly
the book link can be found here
The text in a PDF is not the same as the text used for its construction, we can see that in your example where page 7 is shown in Arabic on the surface but is coded as 7 in the plain text.
However a greater problem is the Languages as supported by fonts, so in Notepad I had to accept a script font to see a similarity, but that is using a font substitution.
Another complication is Unicode and whitespace ordering.
so the result from
pdftotext -f 5 -l 5 في_الأدب_الجاهلي.pdf try.txt
At best will look like
Thus in summary your Sample 1 is equal if not better, than any other simple attempt.
Later Edit from B.A. comment below
I found a way to go around this, after extracting the text I open the txt file and normalize its content using unicodedata python module that offers unicodedata.normalize() function. So I can now say that pdftotext is the best tool for Arabic text extraction
Unicode Normalization should be fixing that issue. (you can choose NFKC)
Most programming languages have a normal.
check here for more info about normalization.
https://unicode.org/reports/tr15/
I have two pdf documents, both in same layout with different information. The problem is:
I can read one perfectly but the other one the data is unrecognizable.
This is an example which I can read perfectly, download here:
from_pdf = camelot.read_pdf('2019_05_2.pdf', flavor='stream', strict=False)
df_pdf = from_pdf[0].df
camelot.plot(from_pdf[0], kind='text').show()
print(from_pdf[0].parsing_report)
This is the dataframe as expected:
This is an example which after I read, the information is unrecognizable, download here:
from_pdf = camelot.read_pdf('2020_04_2.pdf', flavor='stream', strict=False)
df_pdf = from_pdf[0].df
camelot.plot(from_pdf[0], kind='text').show()
print(from_pdf[0].parsing_report)
This is the dataframe with unrecognizable information:
I don't understand what I have done wrong and why the same code doesn't work for both files. I need some help, thanks.
The problem: malformed PDF
Simply, the problem is that your second PDF is malformed / corrupted. It doesn't contain correct font information, so it is impossible to extract text from your PDF as is. It is a known and difficult problem (see this question).
You can check this by trying to open the PDF with Google Docs.
Google Docs tries to extract the text and this is the result:.
Possible solutions
If you want to extract the text, you can print the document to an image-based PDF and perform an OCR text extraction.
However, Camelot does not currently support image-based PDFs, so it is not possible to extract the table.
If you have no way to recover a well-formed PDF, you could try this strategy:
print PDF to an image-based PDF
add a good text layer to your image-based PDF (using OCRmyPDF)
try using Camelot to extract tables
I have multiple pdf files without 'toUnicode' cmap table. Absence of cmap table restricts me from copying the text from pdf files.
As far as I know, there is a possibility to add 'toUnicode' mapping in pdf file, but in my case adding static values is not an option, different files have different glyph codes.
So the question is the following. Is there any possibility to restore 'toUnicode' cmap table, perhaps with the help of Ghostscript, or are there any options at all?
Thanks.
No, you cannot add ToUnicode CMaps to an existing PDF file using Ghostscript.
In the general case, you can't do it at all, except manually. As you note in the question, different files will be constructed to use different character code->Glyph mappings, which means that the character code to Unicode mapping will also be different.
Since the character code selection is often based on the order in which glyphs are used in a file (so the fist glyph is character code 1, the second is character code 2 etc) you can see that there is no prospect of identifying a 'one size fits all' solution.
You could use some kind of OCR to scan the rendered output, identify each glyph and find the Unicode code point for it. Then you could construct a CMap by identifying the character code for the glyph and mapping it to the Unicode value.
You could, then, add the ToUnicode CMap to the PDF file, and update the Font Descriptor with the object number of the ToUnicode CMap.
Ghostscript won't do any of that for you, and I haven't heard of any tool which will.
This may be a stupid question, but I can't figure it out.
I have made some tables in SPSS. Now I want them over to my latex document.
What I do, it that I right-click the table in SPSS, and press export.
Here I can choose between PDF or .doc. BUT the PDF-file created, generates a file with the table on top of a page (A4 size, with "page 1" at the bottom). I do not want this, I only want the table.
example how it turns out:
Example how I want it to turn out:
If I export to word, I can further save as PDF, but same problem occurs.
Screenshot works, but does not give me the same picture-quality that I prefer.
Do anyone of you have any tips for me?
Thanks :)
Unfortunately SPSS does not provide native table export to Latex. It does provide table export to html and xls, which can post-hoc be converted to Tex tables. PDF output for everything forces to export the full page (very annoying for graphics as well) - but you probably don't want to insert the image of the table (you could crop the PDF if need be), but have a Tex table (in the same font) as your document anyway.
One thing I have done in the past to make the export to text tables with specific markup is to use the PRINT or LIST commands to print the text table to the output (or to a text file) that is closer to the end goal. In this NABBLE post I have some syntax that makes pandoc flavored pipe style markdown tables - it should be pretty clear how that same approach could be used for Tex tables (actually Tex tables should be much simpler).
Here is an example of some code using LIST to make a the markup closer to Tex tables.
DATA LIST FREE / Variable (A1) Mean Median (2F4.2).
BEGIN DATA
A 3.25 2.00
B 2.56 2.50
C 9.87 10.20
END DATA.
*Using LIST to make Latex style table.
STRING Mid (A1) End (A2).
COMPUTE Mid = "&".
COMPUTE End = "//".
LIST /VARIABLES = Variable Mid Mean Mid Median End.
And here is a screen shot of the produced output on my machine.
So here I would still have to copy-paste the text output into my Tex document, (and make the header row).
You can also use OMS to save designed items in a variety of formats, including XML and then use an xml-to-Latex tool such as xmltex. You could probably even generate such a conversion with XSLT from the XML.
From the Viewer, you could also retrieve the table with Python scripting and use a Python-based converter tool.
I am trying to extract a range of pages from a multipage pdf file into individual jpegs using convert (Imagemagick). The extraction works fine. What I am stuck on is that if I want to extract page range 10-20, I still get out jpeg files with names page-0.jpeg to page-9.jpeg while I want them to be named page-10.jpeg to page-20.jpeg. Is there a way of specifying that on the command line?
I require this since I want to extract pages in chucks of 10 to avoid eating up too much memory for huge pdf files and don't want to keep renaming the files.
I remember having this working in an earlier project but can't figure out what I am missing now.
Finally managed to do this. Leaving a answer in case somebody else is looking for the same. The solution works with Imagemagick 6.5.1.
So we want to extract page numbered i to j from a.pdf into individual jpegs with files named from a-10.jpeg to a-20.jpeg.
convert a.pdf[i-j] -set filename:page "%[fx:t+i]" a-%[filename:page].jpeg
This uses fx operators. fx:t gives the screen number of current image in sequence and we can add our offset to it.
You can specify the first "page" number used by %d in the output filename by adding the -scene n parameter, e.g.:
convert a.pdf[0-9] -scene 10 a-%d.jpeg
will output a-10.jpeg, a-11.jpeg, etc.