Open Source OCR Software

pdfsandwich generates "sandwich" OCR pdf files, i.e. pdf files which contain only images (but no editable text) will be processed by optical character recognition (OCR) and the text will be added to each page invisibly "behind" the images. pdfsandwich is a command line tool which is supposed to be useful to OCR scanned books or journals. It is able to recognize the page layout even for multicolumn text. Essentially, pdfsandwich is a wrapper script which calls the following binaries: convert, unpaper, tesseract, gs, and hocr2pdf (if tesseract < 3.03). It is known to run on Unix systems and has been tested on Linux and MacOS X. It supports parallel processing on multiprocessor systems. In contrast to most competing sandwich programs, it performs preprocessing of the scanned images, such as de-skewing or removal of dark edges etc. For further information please read the manual: http://www.tobias-elze.de/pdfsandwich/index.html

A Java JNA wrapper for Tesseract OCR API

CRGREP searches for matching text in databases, various document formats, archives and other difficult to access resources. A command line tool for name and content text matching in database tables, plain files, MS Office documents, PDF, archives, MP3 audio, image meta-data, scanned documents, maven dependencies and web resources. CRGREP will search resources within resources of any arbitrary combination or depth, so text within a document within a zip archive, and so on. Here you will find binary downloads and discussion (https://sourceforge.net/p/crgrep/discussion/) . The actual development and issue tracking can be found here: https://bitbucket.org/cryanfuse/crgrep

DjVu++ is a user-friendly program that used to manipulate DjVu file formats such as eBooks with a penalty of editing features. The program introduce a free replacement for the property PDF format with similar resolution and smaller file size DjVu++ also support OCR to handle text in scanned books and images. The program shows good performance for English. In addition to the Arabic language to lead free and commercial software in this area. The main features of DjVu++ program are: o Manipulate DjVu files. o Support smaller size than PDF with the same performance. o DjVu++ supports two languages in the OCR technique (Arabic and English). o Read multiple documents at the same time with the new tabs feature. o DjVu++ supports multiple formats:  Convert PDF document into DjVu format with smaller file size and the same performance.  Convert DjVu into PDF format.  Combine images to a single DjVu document. Perform OCR operations on multiple image formats.

Realtime bigdata tool at the bit level based on immutable AVL forest which can be run in memory or, in future versions, as a merkle forest like a blockchain. Main object is a sparse bit string (Bits) that efficiently scales up to 2^63 bits normally compressed as forest has duplicated substrings. Bits objects support reading bit, byte, short, int, or long (Java primitives) at any bit index in 64 bit range. Example: instead of building a class to hold a header and then data, represent all of that as Bits, subranges of them, and ints for sizes of its parts. Expansion ability for other kinds of compression, since Bits is a Java interface. Main functions on bits are substring, concat, number of 0 or 1 bits, and number of bits (size). All those operations can be done millions of times per second regardless of size because the AVL forest reuses existing branches recursively. Theres a scalar (originally for copy/pasting subranges of sounds) and a bit Java package. Sparse n dimensional matrix.

Neuroph OCR - Handwriting Recognition is developed to recognize hand written letter and characters. It's engine derived's from the Java Neural Network Framework - Neuroph and as such it can be used as a standalone project or a Neuroph plug in.