Tools

Image Retrieval

Text Retrieval

Lemur Toolkit for Language modeling and Information Retrieval
Lucene: full-featured text search engine library in Java
Terrier: effective and robust search engine for large-scale collections
Zettair: compact and fast text search engine in C
WordNet - large lexical database of English
Wikipedia Miner
CRFChunker: CRF English Phrase Chunker
YamCha: Yet Another Multipurpose CHunk Annotator

Visual Feature Extraction

ColorDescriptor - a visual concept detection system
libCRFH - Library for Building Composed Receptive Field Histograms
Software for Unwrapping Omnidirectional Images
SURF: Speeded Up Robust Features
Interest Point Detectors - Local Descriptors - a binary for interest point detection and local descriptor computation.
Affine Covariant Features - Krystian Mikolajczyk's binaries and code for computing various local interest point detectors and affine descriptors.
Bag-of-words demonstration - Matlab code for generating the BOW representation.
Gist - Antonio Torralba's Matlab code to compute global scene features.

Machine Learning

LIBSVM - A C/C++/Matlab/Java Library for Support Vector Machines
Conditional Random Fields - Matlab, java and C++ code for Conditional Random Fields

More useful tools especially from the Natural Language Processing and Machine Translation domain can found on the TrebleCLEF Best Practices web page.

ImageCLEF - Image Retrieval in CLEF

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