Update README

Author: Hiromu Hota

README.rst

@@ -3,7 +3,7 @@ pdftotree
 
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-**WARNING**: ``pdftotree`` *is experimental code and is NOT stable or maintained. It is not integrated with or supported by Fonduer.*
+**WARNING**: ``pdftotree`` *is experimental code and is NOT stable. It is not integrated with or supported by Fonduer.*
 
 Fonduer_ performs knowledge base construction from richly formatted data such
 as tables. A crucial step in this process is the construction of the
@@ -16,8 +16,10 @@ This package is the result of building our own module as replacement to Adobe
 Acrobat. Several open source tools are available for pdf to html conversion but
 these tools do not preserve the cell structure in a table. Our goal in this
 project is to develop a tool that extracts text, figures and tables in a pdf
-document and maintains the structure of the document using a tree data
-structure.
+document and returns them in an easily consumable format.
+
+Up to v0.4.1, pdftotree's output was formatted in its own "HTML-like" format.
+From v0.5.0, it conforms to hOCR_, an open-standard format for OCR results.
 
 Dependencies
 ------------
@@ -49,19 +51,14 @@ pdftotree
 ~~~~~~~~~
 
 This is the primary command-line utility provided with this Python package.
-This takes a PDF file as input, and produces an HTML-like representation of the
-data::
+This takes a PDF file as input and produces an hOCR file as output::
 
     usage: pdftotree [options] pdf_file
 
-    Script to extract tree structure from PDF files. Takes a PDF as input and
-    outputs an HTML-like representation of the document's structure. By default,
-    this conversion is done using heuristics. However, a model can be provided as
-    a parameter to use a machine-learning-based approach.
+    Convert PDF into hOCR.
 
     positional arguments:
-      pdf_file              PDF file name for which tree structure needs to be
-                            extracted
+      pdf_file              Path to input PDF file.
 
     optional arguments:
       -h, --help            show this help message and exit
@@ -71,8 +68,8 @@ data::
       -m MODEL_PATH, --model_path MODEL_PATH
                             Pretrained model, generated by extract_tables tool
       -o OUTPUT, --output OUTPUT
-                            Path where tree structure should be saved. If none,
-                            HTML is printed to stdout.
+                            Path to output hOCR file. If not given, it will be
+                            printed to stdout.
       -f FAVOR_FIGURES, --favor_figures FAVOR_FIGURES
                             Whether figures must be favored over other parts such
                             as tables and section headers
@@ -207,3 +204,4 @@ Then you can run our tests::
 .. _version file: https://github.com/HazyResearch/pdftotree/blob/master/pdftotree/_version.py
 .. _editable mode: https://packaging.python.org/tutorials/distributing-packages/#working-in-development-mode
 .. _flake8: http://flake8.pycqa.org/en/latest/
+.. _hOCR: http://kba.cloud/hocr-spec/1.2/