Child pornography (CP) is a term that broadly describes all multimedia and writings that depict sexual activities involving a child. As at 2008, 94 of 187 Interpol member states refer to CP as a crime in their code of laws. Of these, possession of such content is punishable in 58 countries.

INACT is a software suite designed for law enforcement, experts, non-governmental organizations and all other entities involved in combating of CP. It was developed in close cooperation with end users and carefully engineered in order to automate tedious and time consuming tasks of file system search.

INACT software is divided into a set of two applications and a database module utilizing the Query by Example (QbE) approach:

  • INACT INDEXER for indexing multimedia (images and movies)
  • INACT SEARCHER for searching within file systems using the QbE principle and fully automatically using hashes created by the INDEXER
  • Database module

The first application, INACT INDEXER is used to catalogue media during the everyday duties of the experts. INACT INDEXER extracts the high- and low level metadata of the media and stores it into a centralized database. While the low-level metadata computation is time consuming, INACT INDEXER works automatically and without supervision. The user has to provide only a path to a catalogue containing the media.

INACT INDEXER is designed to be used in a distributed manner, exchanging data via a private cloud. In such setup multiple instances of INDEXERs may be used simultaneously in different location while contributing to a single database.

Second application of the suit is the INACT INSEARCHER. This application is designed to perform search of images and video clips similar or identical to the ones that were indexed into the INACT cloud within the file system of a suspect. INACT INSEARCHER can be used as a standalone application or executed as a Live USB Operating System, as it is integrated with the DEFT Forensic Linux. Before searching the operator has to download the newest set of metadata from the INACT cloud.


    • INACT is capable of indexing photographs and movies
    • Indexing is fully automated and requires no IT skills to perform
    • Indexing is a one way process, the images cannot be recreated from the index, so it can be legally stored and even shared
    • Index consists of low- and high level metadata

    • Allows for fully automated search within file system
    • Allows to find identical (MD5) and visually similar media items, such that were:
      • recompressed
      • rescaled
      • manipulated in a media manipulation software by e.g. distorting the face of a person or cropping a part of an image
      • Origin from the same photographic session
      • modified by manipulating high-level metadata held in EXIF or AVI headers.
    • Results are presented in real time to the operator
    • Implements a state-of-the art intelligent algorithms that speed up the search process by 7x (compared to automated random search,link)
    • Is integrated with DEFT Forensic Linux in form of a live USB operating system
    • Implements a revolutionary algorithm for automated, unsupervised and sample-less identification of CP images and movies (implementation pending)

  • INACT Database:
    • Provides a private cloud environment for exchange of index items
    • Allows for multiple instances of INACT INDEXERs and INACT SEARCHERs to be used at the same time
    • Provides state of the art security mechanisms for maximum safety of the data

Fig 1. Inact Database

Fig 2. Inact Database

Media and Publications

  • Publications:

    • INACT—INDECT Advanced Image Cataloguing Tool, Michał Grega, Damian Bryk, Maciej Napora, Multimedia Tools and Applications , July 2012, link

    • INACT — INDECT Advanced Image Cataloguing Tool, Michał Grega, Damian Bryk, Maciej Napora, Marcin Gusta Multimedia Communications, Services and Security Communications in Computer and Information Science Volume 149, 2011, pp 28-36 link

    • Performance evaluation of INACT-INDECT advanced image cataloguing tool, Libor Michalek, Michał GREGA, Damian Bryk, Bartłomiej Grabowski, Advances in Electrical and Electronic Engineering ; ISSN 1336-1376, 2012 vol. 10 nr 4 spec. iss. s. 308–311 link
  • Screenshots:

  • Fig 1. Inact Indexer

    Fig 2. Inact Indexer

    Fig 3. Inact Insearcher


INACT is a complex suite of software, tailored for the need of a specific user. Please contact us, we will be more than happy to provide you a fully functional deployment for the INACT suite for testing purpose for free.

Offer and Contact

INACT is offered

  • As a Software as a Service paradigm
  • As a licence for a software suite with or without support
  • As a licence for separate components or algorithms

If interested, please reach us at inact(at)kt.agh.edu.pl Person responsible:
Michał Grega, PhD Eng.

Last update - JUN 2013