Direct Access Archive, or DAA, is a proprietary file format developed by PowerISO Computing, Inc for

disk image A disk image is a snapshot of a storage device's content typically stored in a file on another storage device. Traditionally, a disk image was relatively large because it was a bit-by-bit copy of every storage location of a device (i.e. every ...

files. The format supports features such as compression, password protection, and splitting to multiple volumes. Popular Windows disk image mounting programs such as

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and

Daemon Tools DAEMON Tools is a virtual drive and optical disc authoring program for Microsoft Windows and Mac OS. Overview DAEMON tools was originally a successor of ''Generic SafeDisc emulator'' and incorporated all of its features. The program claim ...

currently do not support the mounting of DAA images; Linux and BSD also do not support mounting images of this kind. Currently there is no published information about the format. Among mainstream applications, it can be opened or converted with MagicISO and UltraISO. Various free and open-source packages are also available to convert DAA to ISO images.

File Structure

Although lacking official documentation, DAA image files are

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- or lzma-compressed

ISO image An optical disc image (or ISO image, from the ISO 9660 file system used with CD-ROM media) is a disk image that contains everything that would be written to an optical disc, disk sector by disc sector, including the optical disc file system. IS ...

s chunk by chunk.

Conversion

''PowerISO'' provides free command-line tools for

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and

Mac OS X macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

which allow the user to extract DAA files or convert them into

ISO The International Organization for Standardization (ISO ; ; ) is an independent, non-governmental, international standard development organization composed of representatives from the national standards organizations of member countries. Me ...

format, however these tools have not been updated to support the newest version of the DAA format. The PowerISO

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

trial version only supports converting images from DAA files up to 300MB, less than half of the capacity of a standard CD. '' AcetoneISO'' is a free CD/DVD management application for Linux that can convert DAA to ISO with the help of the external PowerISO command-line tool for Linux. ''daa2iso'' is an open source

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application has been developed to convert DAA files to ISO files. The program comes with a Windows binary and source code which compiles under Unix-like operating systems. daa2iso allows users to select the .daa file, and the location for the .iso output via standard windows open and save dialogs For Mac OS X, ''DAA Converter''DAA Converter for Mac OS X
/ref> is a GUI application which wraps the daa2iso command-line tool (GNU license).

Features

Due to using freely available compression algorithms, DAA includes the following features that are absent in ISO (but can be obtained by manually compressing ISO files): *Ability to compress images, thus saving space and allowing smaller downloads *Can be password protected *Can be split into multiple smaller files

References

External links

PowerISO Website
{{Disk_images Disk images Archive formats