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A '''disk image''' is a [[computer file]] containing the complete contents and structure of a [[data storage device]]. The term has been generalized to cover any such file, whether taken from an actual physical storage device or not. ## page was renamed from disk image
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An ordinary backup only backs up the files it can access; [[booting|boot]] information, and files locked by an [[operating system]] or being changed at the time, may not be saved. A disk image contains all these, and faithfully replicates the data, so it is commonly used for backing up disks with operating systems, or bootable CD/DVD s. A '''[[WikiPedia:Disk_image|disk image]]''' is a computer file containing the complete contents and structure of a data storage device.
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The image is saved as a file, which for a full CD or system disk may be quite large (~10 MB to several GB). This file can be saved onto a [[hard drive]], CD, DVD or other media, for later use. The term has been generalized to cover any such file, whether taken from an actual physical storage device or not.
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Disk images can either be compressed using some type of [[compression algorithm]] like LZW, or uncompressed ("raw"). Images of CD-ROM s most often carry the file name extension .[[ISO image|iso]], referring to the ISO 9660 file system commonly used on such discs. The .iso format is the most common format for Linux distributions]] and other online images. Other common CD image formats are .bin/.cue. A common use of disk images is for remote distribution of software such as Linux distributions: installation [[CDDVD|CD/DVDs]] can be recorded as disk image files, transferred over the Internet, and the contents of the original disk(s) duplicated exactly by end users with their own CD/DVD drives. They are commonly used to distribute [[LiveCD|Live CDs]].
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== .bin ==
.bin files (or .RAW files) are images extracted in pure RAW format. That is 2352 bytes sectors, the full CD sector content: user data, sector header, error correction codes (ECC) and error detection codes (EDC). Once again, each sector is converted to digital data in the .BIN file, but more stuff is copied and the resulting file will be bigger. The .BIN file should be 251,000 x 2352 = 590,352,000 bytes big. This process will copy ANYTHING on the disc, so it is useful for exotic discs (multiple tracks, mixed track type Audio+Data or Data+Audio) and for non-PC CDs (PSX, VCD, MAC).
Another common use is to provide virtual disk drive space to be used by SystemVirtualization. This can prevent the CD from getting burned or damaged. It can also reduce bulk when one wishes to carry the contents of the CD along with oneself: one can store disk images to a relatively lightweight and bootable storage device which has a higher storage capacity than that of a CD (i.e. a USB keydrive).

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The ["iso image"] file is a digital copy of CD contents made this way: the ripper searches for the sectors of the CD that have been used, say 251,000 for instance (there are 330,000 sectors on a 74 min CD and 360,000 sectors on a 80 min CD). Each sector is copied on the .ISO file, one by one, and only 2048 bytes for each sector (only the ones containing the user data) are copied. The .ISO file should then be of size 251,000 x 2048 = 514,408,000 bytes. (It will be slightly bigger if the extractor puts a header on the file, like Nero .NRG files that are .ISO files plus a small file header).
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== .img ==
.img is the filename extension usually use for the disk image of floppy disks, and sometimes, hard disks. First populated by DOS-based software HD-Copy DiskDupe and now WinRaWrite, is a handy way to archive a floppy disk completely, including bootable ones. In fact there is no "format" in it, just a raw dump of the content of the disk.
An '''[[WikiPedia:ISO_image|ISO image (.iso)]]''' is an informal term for a disk image of an ISO 9660 FileSystem. More loosely, it refers to any optical disk image.
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Some newer software like Some newer software like WinImage supports zipped version of the format and the extension is .imz. As is typical for disk images, in addition to the data files that are contained in the ISO image, it also contains all the filesystem metadata (Boot code, structures, and attributes). All of this information is contained in a single file. These properties make it an attractive alternative to physical data storage device for the distribution of software which requires this additional information as it is simple to retrieve over the Internet. It is commonly used fir the distribution of Linux and [[LiveCD|LiveCDs]].
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== Usage == You can create, open and mount ISO images using [[CDDVDTools|CD and DVD applications]]. See [[ManipulatingISOs]] for info on manipulating ISO disk images.
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A common use of disk images is for remote distribution of software such as Linux distributions: installation floppy disks or CD-ROMs can be recorded as disk image files, transferred over the Internet, and the contents of the original disk(s) duplicated exactly by end users with their own floppy or CD-R drives. So, user can burn the Isos to convert them in LiveCD s, to try an Operating System, without installing it in the hard disk . ISO images have the [[MIME]] type {{{ application/x-iso-image }}}
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Another common use is to provide virtual disk drive space to be used by emulators (i.e. ["qemu"]). This can prevent the CD from getting burned or damaged. It can also reduce bulk when one wishes to carry the contents of the CD along with oneself: one can store disk images to a relatively lightweight and bootable storage device which has a higher storage capacity than that of a CD (i.e. a USB keydrive). == .bin / .raw / .img ==

{{{.bin}}}, {{{.raw}}}, or {{{.img}}} files are images extracted in pure RAW format.

For a CD, that is 2352 bytes sectors, the full CD sector content: user data, sector header, error correction codes (ECC) and error detection codes (EDC). Once again, each sector is converted to digital data in the .BIN file, but more stuff is copied and the resulting file will be bigger. The .BIN file should be 251,000 x 2352 = 590,352,000 bytes big. This process will copy ANYTHING on the disc, so it is useful for exotic discs (multiple tracks, mixed track type Audio+Data or Data+Audio) and for non-PC CDs (PSX, VCD, MAC).

This extension is also commonly used for hard disk images.

=== .cue ===

Sometimes {{{.bin}}} images come with a [[WikiPedia:Cue_sheet_(computing)|cue file]], describing the layout of CD tracks.

You can burn a CD using the information from the cue file with [[DebPkg:cdrdao]]: {{{ cdrdao write --speed 4 --device 0,1,0 example.cue }}}

<<Anchor(dmg)>>
== .dmg ==

A DMG file is an '''[[WikiPedia:Apple_Disk_Image|Apple Disk Image]]''', a popular format on Mac OS X. It is widely used for software distribution means, and is actually the raw image of a HFS filesystem, that's why in Mac OS X it is mounted as a drive.

DMG disk images have the [[MIME]] type {{{ application/x-apple-diskimage }}}

To create a .dmg image from a HFS formatted CD or hard drive partition: {{{ dd if="your input file" of=image.dmg }}}

To mount a .dmg disk image to a directory, you need to install the [[DebPkg:hfsplus]] package, then mount it with {{{ mount -o loop -t hfs image.dmg /mnt/somewhere }}}

== .nrg ==

.nrg is a [[WikiPedia:Nero_Burning_ROM|Nero]] disk image.

You can mount it to a directory using: {{{ mount -o loop,offset=307200 imagename.nrg /mount-point }}}

== See also ==

 * [[CDDVDTools|CD and DVD applications]]

== External links ==
 * Windows software: [[https://www.7-zip.org|7-zip]] and [[http://infrarecorder.org/|Infra recorder]] can be used to read and burn ISO images on Windows, respectively.


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CategorySoftware CategoryFileFormat

Translation(s): Deutsch - English - Français - Italiano - Русский

(!) ?/Discussion


A disk image is a computer file containing the complete contents and structure of a data storage device.

The term has been generalized to cover any such file, whether taken from an actual physical storage device or not.

A common use of disk images is for remote distribution of software such as Linux distributions: installation CD/DVDs can be recorded as disk image files, transferred over the Internet, and the contents of the original disk(s) duplicated exactly by end users with their own CD/DVD drives. They are commonly used to distribute Live CDs.

Another common use is to provide virtual disk drive space to be used by SystemVirtualization. This can prevent the CD from getting burned or damaged. It can also reduce bulk when one wishes to carry the contents of the CD along with oneself: one can store disk images to a relatively lightweight and bootable storage device which has a higher storage capacity than that of a CD (i.e. a USB keydrive).



.iso

An ISO image (.iso) is an informal term for a disk image of an ISO 9660 FileSystem. More loosely, it refers to any optical disk image.

As is typical for disk images, in addition to the data files that are contained in the ISO image, it also contains all the filesystem metadata (Boot code, structures, and attributes). All of this information is contained in a single file. These properties make it an attractive alternative to physical data storage device for the distribution of software which requires this additional information as it is simple to retrieve over the Internet. It is commonly used fir the distribution of Linux and LiveCDs.

You can create, open and mount ISO images using CD and DVD applications. See ManipulatingISOs for info on manipulating ISO disk images.

ISO images have the MIME type  application/x-iso-image 

.bin / .raw / .img

.bin, .raw, or .img files are images extracted in pure RAW format.

For a CD, that is 2352 bytes sectors, the full CD sector content: user data, sector header, error correction codes (ECC) and error detection codes (EDC). Once again, each sector is converted to digital data in the .BIN file, but more stuff is copied and the resulting file will be bigger. The .BIN file should be 251,000 x 2352 = 590,352,000 bytes big. This process will copy ANYTHING on the disc, so it is useful for exotic discs (multiple tracks, mixed track type Audio+Data or Data+Audio) and for non-PC CDs (PSX, VCD, MAC).

This extension is also commonly used for hard disk images.

.cue

Sometimes .bin images come with a cue file, describing the layout of CD tracks.

You can burn a CD using the information from the cue file with cdrdao:  cdrdao write --speed 4 --device 0,1,0 example.cue 

.dmg

A DMG file is an Apple Disk Image, a popular format on Mac OS X. It is widely used for software distribution means, and is actually the raw image of a HFS filesystem, that's why in Mac OS X it is mounted as a drive.

DMG disk images have the MIME type  application/x-apple-diskimage 

To create a .dmg image from a HFS formatted CD or hard drive partition:  dd if="your input file" of=image.dmg 

To mount a .dmg disk image to a directory, you need to install the hfsplus package, then mount it with   mount -o loop -t hfs image.dmg /mnt/somewhere 

.nrg

.nrg is a Nero disk image.

You can mount it to a directory using:  mount -o loop,offset=307200 imagename.nrg /mount-point 

See also

  • Windows software: 7-zip and Infra recorder can be used to read and burn ISO images on Windows, respectively.


CategorySoftware CategoryFileFormat