CDimg|tools is a set of command line tools to inspect and manipulate CD/DVD optical disc images of formats uncommon on free UNIX-like systems (like GNU/Linux or BSD).

One sort of tool is concerned with a certain special image file format, possibly a non open one. It can print information about an image file in this format, or extract parts of its data (e.g. audio tracks or disc sessions) to files in “raw” format, so that they can be further processed by more widely available tools (e.g. for the purpose of playing audio, reading files, burning tracks or sessions to optical media).

  • NRG is the only supported format for the present.

Another sort of tool is concerned with the processing of files in a “raw” format. It can convert between different variations of formats of the same type, or convert from a raw format to an equivalent well-known self-describing format, or modify the raw data without changing its format. For the present it is possible:

  • to demultiplex RAW+96 image files containing both stream data and sub-channel data,

  • to decrypt CSS-scrambled VOB files,

  • and to decrypt CSS-scrambled DVD Video image files.

CDimg|tools was mainly written under a GNU/Linux OS but should work under other UNIX flavours, and perhaps even on other platforms, albeit maybe only partially (see the file INSTALL for a list of dependencies).

Commands in the package


This command is a Perl script that demultiplexes/multiplexes stream data (audio, raw data or .iso format data) and sub-channel data from a RAW+96 image file. It handles optical disc images containing stream data and sub-channel data of a given sector at contiguous positions; this kind of image file may be either directly created by a ripping program like readcd(1) or cdrdao(1), or extracted from another image file by nrgtool(1).


This command is a Perl script that reads .nrg images (created by Nero), prints the metadata about the image, and extracts, for each track, the raw data to a separate file; disc types such as CDDA, CD-extra and (multi-session) CD-ROM/DVD-ROM are supported.


This command decrypts CSS-scrambled VOB files or streams found on DVD Video discs; the title key is obtained transparently by libdvdcss.


This command decrypts CSS-scrambled DVD Video discs or image files; it writes a similar image file containing the same data at the same location; the UDF filesystem of the disc is left intact.


  • The official homepage is at Gna!. There you might find up-to-date information and releases.

  • UNIX manual pages that contain usage examples are available for each command.

  • Known bugs and limitations are mentioned in the section about issues.

  • Release notes listing important user-visible changes are available in a separate file NEWS.

Installation instructions

Download and installation instructions and a list of dependencies can be found in the file INSTALL.


Known bugs and limitations:

  • The image formats handled by some tools are not open: their logic can only be guessed from sample files. Consequently there can be absolutely no guarantee that a tool can handle all files of the same formats appropriately.

  • For bugs and limitations specific to a particular command, see its manual page.

  • Bugs recently discovered or other minor bugs may be listed online at

Bug reports and feature requests are managed with the web issue trackers at Gna!. To submit a bug report:

  1. Check that the bug is not already known, by searching the sources listed above; if it is already known, and if applicable, you might want to confirm the bug, cite some other problematic cases etc.

  2. Try to reproduce the problem with the most up-to-date released version available online.

  3. To submit a report about a new bug, fill in the form of the suport tracker; you do not need a Gna! account, although you can log in.

Credits & License

CDimg|tools was written by GĂ©raud Meyer (g_raud chez

CDimg|tools is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.

This package is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

The full text of the license can be found in the root directory of the project sources, in the file COPYING. Otherwise see