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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
#language en
||<tablewidth="100%"style="border: 0px hidden ;">~-[[DebianWiki/EditorGuide#translation|Translation(s)]]: English - [[fr/DiskImage|Français]] - [[it/DiskImage|Italiano]]-~ ||<style="border: 0px hidden ; text-align: right;"> (!) [[/Discussion]] ||
----
 . 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. ''[[WikiPedia:Disk_Image|See more]]...''
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 images to convert them in LiveCD s, to try an Operating System, without installing it in the hard disk .
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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. 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 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.

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.
<<TableOfContents(2)>>
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== .ISO ==
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).
<<Anchor(iso)>>
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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.
== .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.
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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.
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== Usage == Some of the common uses include the distribution of Linux and LiveCD s.
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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 . === Mime ===
[[MIME]] type
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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). {{{
 application/x-iso-image
}}}
=== How to create it ===
You can create it with a [[CDDVDTools|CD and DVD applications]]

__Command Line Interface: __

Ways for copying a CD to a file (this is, create an iso file):

{{{
 dd if=/dev/cdrom of=image.iso
}}}
=== How to use it ===
You can open it with a [[CDDVDTools|CD and DVD applications]]

__ Command Line Interface: __

{{{
 mount -o loop -t iso9660 image.iso /mnt/''somewhere''
}}}
<<Anchor(dmg)>>

== .dmg ==
A DMG file ('''d'''isk i'''m'''a'''g'''e) is 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.

=== Mime ===
[[MIME]] type

{{{
application/x-apple-diskimage}}}
=== How to create it ===
AFAIK the only way to create under Debian it is to use the command line:

{{{
 dd if="your input file" of=image.dmg
}}}
Where "your input file" is a HFS formatted CD or hard drive partition.

But creating a DMG file under Linux makes no sense, since there are many other ways of packing your data, such as file archivers.

=== How to use it ===
First you have to install hfsplus (do it as root):

{{{
 apt-get install hfsplus
}}}
Since your DMG is a raw hfs filesystem, you can mount it the same way as an ISO image, just change "iso9660" to "hfs" after the -t (type) switch.

{{{
 mount -o loop -t hfs image.dmg /mnt/''somewhere''
}}}
Of course, you must do this as root, and the target directory has to be created first.

After that the files will be available in the target directory.

'''Although I haven't tested it, I think that if the DMG file is compressed or protected in any way, you won't be able to mount it.'''

It worked for me and may or may not work for you.''' '''

== .img ==
.img is the filename extension usually use for the disk image of floppy disks, and sometimes, hard disks. First popularized 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.

Some newer software like Some newer software like !WinImage supports zipped version of the format and the extension is .imz.

== .nrg ==
.nrg is a Nero Image.

You can mount it as follows:
{{{
 sudo mount -o loop,offset=307200 imagename.nrg /mount-point
}}}


== External links ==
 * wikipedia: WikiPedia:iso_image
 * DebPkg:iat - ''Converts many CD-ROM image formats to iso9660 ( BIN, MDF, PDI, CDI, NRG, and B5I)''
 * Windows users:
  * !SlySoft Virtual !CloneDrive ''(mount and ISO)'' ~-<<BR>>. http://www.slysoft.com/en/virtual-clonedrive.html-~ -~
  * [[http://www.smart-projects.net/isobuster/|IsoBuster]] and [[http://www.7-zip.org|7-zip]] let you browse the content of an ISO image.
  * [[http://infrarecorder.sourceforge.net/|Infra recorder]] and [[http://isorecorder.alexfeinman.com/isorecorder.htm|Iso Recorder]] let you burn CD/DVD/BD Iso images.
----
 . See also: [[CDDVDTools|CD and DVD applications]] - IsoBuster - [[genisoimage]] (replace mkisofs)
 . CategorySoftware

Translation(s): English - Français - Italiano

(!) ?/Discussion


  • 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. See more...

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 images to convert them in LiveCD s, to try an Operating System, without installing it in the hard disk .

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).

.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).

.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.

Some of the common uses include the distribution of Linux and LiveCD s.

Mime

MIME type

 application/x-iso-image

How to create it

You can create it with a CD and DVD applications

Command Line Interface:

Ways for copying a CD to a file (this is, create an iso file):

 dd if=/dev/cdrom of=image.iso

How to use it

You can open it with a CD and DVD applications

Command Line Interface:

 mount -o loop -t iso9660 image.iso /mnt/''somewhere''

.dmg

A DMG file (disk image) is 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.

Mime

MIME type

application/x-apple-diskimage

How to create it

AFAIK the only way to create under Debian it is to use the command line:

 dd if="your input file" of=image.dmg

Where "your input file" is a HFS formatted CD or hard drive partition.

But creating a DMG file under Linux makes no sense, since there are many other ways of packing your data, such as file archivers.

How to use it

First you have to install hfsplus (do it as root):

 apt-get install hfsplus

Since your DMG is a raw hfs filesystem, you can mount it the same way as an ISO image, just change "iso9660" to "hfs" after the -t (type) switch.

 mount -o loop -t hfs image.dmg /mnt/''somewhere''

Of course, you must do this as root, and the target directory has to be created first.

After that the files will be available in the target directory.

Although I haven't tested it, I think that if the DMG file is compressed or protected in any way, you won't be able to mount it.

It worked for me and may or may not work for you.

.img

.img is the filename extension usually use for the disk image of floppy disks, and sometimes, hard disks. First popularized 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.

Some newer software like Some newer software like WinImage supports zipped version of the format and the extension is .imz.

.nrg

.nrg is a Nero Image.

You can mount it as follows:

 sudo mount -o loop,offset=307200 imagename.nrg /mount-point