In the office reality, we live fast, work a lot and often dream of a helping hand. Its digital form can be the optical character recognition (OCR) technology used in most PDF software, which allows you to move everyday work with documents to a more efficient level.
OCR
technology can do much more than just digitize old documents, it allows you to
transform working with multiple PDF files into a truly digital experience, thus
supporting your PDF conversion as well, such as PDF to HTML.
Why OCR for PDF?
Most
PDFs are great for on-screen viewing, but things get a lot more difficult when
you want to effectively analyze, modify, and reuse their content. The files
don’t contain information about the structure of the document. This means that
we don’t know from the file itself which parts are text, images, lines, or
other elements.
We
can’t tell what each of these elements does or how they relate to each other. This
is where OCR can help with identification.
How does OCR work?
Going
beyond working with a PDF document as a whole or with a set of pages, OCR
enables working with the content of the document. This includes text editing,
full-text searching, table extraction, and document comparison. This requires a
content recognition process consisting of three main stages.
First,
the document pages are checked using a Document Analysis system, which almost
literally “looks” at each page and examines the image to detect the smallest
parts that may be separate words and characters. At this stage, the software
also detects barcodes, and also analyzes tables to find out which parts of the
table image are separators and which are cells, and what is in each of them.
The
second step is to learn all the previously detected bits. OCR “reads” the
images of each character or combination of characters, giving us digital text
in the form of a code for further work.
In
the third step, the Synthesis system comes into play. Once the process is
complete, we have information about where the texts, images, and tables are on
the page, the location of table cells and separators, and other details such as
how the image is separated into lines and words and where this happens on the
page.
Paragraph-level editing of PDFs
Editing
a paragraph in an OCR-processed PDF becomes easy. The text is extracted from
the PDF as it exists. OCR detects the tags that we need to know and follow to
edit the entire paragraph correctly.
Digital
text extracted from the PDF file itself adapts to the detected structure,
allowing the user to edit the page. Because the program knows and can track the
paragraph structure, text changes during editing are performed smoothly. This
allows for line-to-line transitions and maintaining the consistency of lines
and character spacing, and the font is selected automatically. Changes are
displayed in real time.
When
a user finishes editing, only the part that was changed will be updated in the
PDF. Since the changes are made to the original document itself, everything
that was not edited retains its original form.
Extracting tables
OCR
also helps to use tables effectively by extracting them directly from PDF
files. To enable us to fully edit, OCR can describe and recreate the structure
of a table based on its image – this way we get an extracted, fully rasterized
version.
Thanks
to this, the user can easily edit the data "read" by the software or
paste the entire table into another application, such as DWG, Excel or Word.
Compare PDF documents
OCR
also helps compare digital PDF files. It compares two copies of a document in
any format, not just PDF, which allows you to detect any differences between
them. Documents can confuse us, for example when the same text is formatted
differently or placed slightly differently on the page, but the general order
of display of the text has not changed. Here again, analysis of the document
structure, which we learn thanks to the use of OCR-related tools, is helpful.
These
are just three examples of operations on PDF files that use OCR technology or
even depend on it. There are many more such applications. Therefore, it is easy
to say that using OCR-supported PDF software can significantly simplify
everyday work with documents and make it faster and more effective, without the
need for even tedious rewriting of documents that we want to work on.
