| Revision as of 13:03, 6 March 2014 editCodename Lisa (talk | contribs)55,077 edits Reverted 1 edit by 217.174.103.105 (talk): Preview button is there for a reason, you know.← Previous edit | Latest revision as of 19:57, 27 November 2022 edit undoSWinxy (talk | contribs)Extended confirmed users, Template editors12,778 editsm →top: MOS:ORDERTag: 2017 wikitext editor | ||
| (36 intermediate revisions by 29 users not shown) | |||
| Line 1: | Line 1: | ||
| {{short description|Computer file format}} | |||
| {{About|a raw disk image file format with .img filename extension|Apple Inc.'s disk images using the .img filename extension|Apple Disk Image|disk images based on the ISO 9660 file system|ISO image|the GPS device map format|Garmin .img}} | {{About|a raw disk image file format with .img filename extension|Apple Inc.'s disk images using the .img filename extension|Apple Disk Image|disk images based on the ISO 9660 file system|ISO image|the GPS device map format|Garmin .img}} | ||
| {{ref improve|date=February |
{{ref improve|date=February 2019}} | ||
| {{Infobox file format | |||
| ⚫ | '''IMG''', in computing, refers to ]s with <code>.img</code> ] that store raw ] of ]s, ]s, |
||
| | mime = application/x-ima <ref>{{cite web |url=https://www.sitepoint.com/mime-types-complete-list/|title=MIME Types - the Complete List|date=15 August 2015 }}</ref> | |||
| | extensions = .img, .ima | |||
| }} | |||
| ⚫ | '''IMG''', in computing, refers to ]s with the <code>.img</code> ] that store raw ] of ]s, ]s, and ]s or a ] – <code>.img</code>. | ||
| ==Overview== | ==Overview== | ||
| The <code>.img</code> ] is used by ] files, which contain raw dumps of a ] or of an ]. Since a raw image consists of a ]-by-sector binary copy of the source medium, the actual format of the file contents will depend on the ] of the disk from which the image was created (such as a version of ]). Raw disk images of ] (such as ]s and ]s) contain a raw image of all the ] in a disc (which can include audio, data and video tracks). In the case of ]s and DVDs, these images usually include not only the data from each sector, but the ] and error correction fields for each sector as well. | The <code>.img</code> ] is used by ] files, which contain raw dumps of a ] or of an ]. Since a raw image consists of a ]-by-sector binary copy of the source medium, the actual format of the file contents will depend on the ] of the disk from which the image was created (such as a version of ]). Raw disk images of ] (such as ]s and ]s) contain a raw image of all the ] in a disc (which can include audio, data and video tracks). In the case of ]s and DVDs, these images usually include not only the data from each sector, but the ] and error correction fields for each sector as well. | ||
| Since IMG files hold no additional data beyond the disk contents, these files can only be handled by programs that can detect their ]s. For instance, a typical raw disk image of a floppy disk begins with a ], which can be used to identify its file system. Disc images of optical media are usually accompanied by a descriptor file which describes the layout of the disc, and includes information such as track limits which are not stored in the raw image file. | Since IMG files hold no additional data beyond the disk contents, these files can only be automatically handled by programs that can detect their ]s. For instance, a typical raw disk image of a floppy disk begins with a ], which can be used to identify its file system. Disc images of optical media are usually accompanied by a descriptor file which describes the layout of the disc, and includes information such as track limits which are not stored in the raw image file. | ||
| ===Filename extensions and variants=== | ===Filename extensions and variants=== | ||
| The <code>.img</code> file extension was originally used for ] raw disk images only. A similar file extension, <code>.ima</code>, is also used to refer to floppy disk image files by some programs. A variant of IMG, called IMZ, consists of a ]ped version of a raw floppy disk image. These files use the <code>.imz</code> file extension, and are commonly found in compressed images of floppy disks created by |
The <code>.img</code> file extension was originally used for ] raw disk images only. A similar file extension, <code>.ima</code>, is also used to refer to floppy disk image files by some programs. A variant of IMG, called IMZ, consists of a ]ped version of a raw floppy disk image. These files use the <code>.imz</code> file extension, and are commonly found in compressed images of floppy disks created by WinImage. | ||
| ] uses the <code>.img</code> file extension for raw images of ] disks, calling the format simply "raw". | ] uses the <code>.img</code> file extension for raw images of ] disks, calling the format simply "raw". | ||
| Line 17: | Line 23: | ||
| ===Size=== | ===Size=== | ||
| The file size of a raw disk image is always a multiple of the sector size. For floppy disks and hard drives this size is typically 512 bytes (but other sizes such as 128 and 1024 exist). More precisely, the file size of a raw disk image of a magnetic disk corresponds to: | The file size of a raw disk image is always a multiple of the sector size. For floppy disks and hard drives this size is typically 512 bytes (but other sizes such as 128 and 1024 exist). More precisely, the file size of a raw disk image of a magnetic disk corresponds to: | ||
| : |
:<abbr title="CHS">Cylinders × Heads × (Sectors per track) × (Sector size)</abbr> | ||
| E.g. for 80 cylinders (tracks) and 2 heads (sides) with 18 sectors per track: | E.g. for 80 cylinders (tracks) and 2 heads (sides) with 18 sectors per track: | ||
| : |
:80 × 2 × 18 × 512 = 1,474,560 bytes or 1440 ] | ||
| For optical discs such as CDs and DVDs, the raw sector size is usually 2,352, making the size of a raw disc image a multiple of this value. | For optical discs such as CDs and DVDs, the raw sector size is usually 2,352, making the size of a raw disc image a multiple of this value. | ||
| ==Comparison to ISO images== | ==Comparison to ISO images== | ||
| ]s are another type of optical disc image files, which commonly use the <code>.iso</code> file extension, but sometimes use the <code>.img</code> file extension as well. They are similar to the raw optical disc images, but contain only one track with computer data obtained from an optical disc. They |
]s are another type of optical disc image files, which commonly use the <code>.iso</code> file extension, but sometimes use the <code>.img</code> file extension as well. They are similar to the raw optical disc images, but contain only one track with computer data obtained from an optical disc. They cannot contain multiple tracks, nor audio or video tracks. They also do not contain the control headers and error correction fields of ] or ] sectors that raw disc images usually store. Their internal format follows the structure of an ] file system, commonly ] (for CDs) or ] (for DVDs). The ] and ] formats, which usually contain raw disc images, can also store ISO images instead. | ||
| ==IMG as an image file format== | |||
| <code>.img</code> is also a planar bitmap graphics file using simple run-length encoding, originating with ]'s ]. It was commonly used on the ] line of home computers, but also with some GEM-based PC software such as ] or ]. | |||
| ==Other disk image files== | |||
| {{main|Apple Disk Image}} | |||
| {{main|Garmin .img}} | |||
| In addition, <code>.img</code> is an ] used by the Mac OS X or ] operating system. | |||
| ] is a hard-disk image file format which contains a header and many subfiles and used to store the maps for its ] units. | |||
| ==Tools== | ==Tools== | ||
| The raw IMG file format is used by several tools: | The raw IMG file format is used by several tools: | ||
| * RaWrite and |
* RaWrite and WinImage use the IMG disk image format to read and write floppy disk images. | ||
| * ] and can mount a raw image of a floppy disk to emulate a floppy drive under ]. | * ] and can mount a raw image of a floppy disk to emulate a floppy drive under ]. | ||
| * ] supports reading IMG files for creating ]s. | * ] supports reading IMG files for creating ]s. | ||
| * ] allows manipulation of ] floppy disk images in ] systems. | * ] allows manipulation of ] floppy disk images in ] systems. | ||
| * Programs such as ''dsktrans'' from the ''LibDsk''<ref></ref> suite of command-line tools (available for ], ], and ]) will convert between different raw disk image formats. | * Programs such as ''dsktrans'' from the ''LibDsk''<ref></ref> suite of command-line tools (available for ], ], and ]) will convert between different raw disk image formats. | ||
| * ] can be used in ] to create raw disk image files of disks. | * ] can be used in ] to create raw disk image files of disks. | ||
| * ] uses IMG files as its default format for ] disk images. | * ] uses IMG files as its default format for ] disk images. | ||
| * ] with the plugin "FORMATS" (''formats.dll'') supports viewing GEM-IMG vector graphics. | |||
| * can read and write disk images to/from USB drives. | |||
| * Garmin MapSource or GPSMapEdit can be used to read Garmin hard-disk image <code>.img</code> format. | |||
| * VLC can play DVD IMG files. | |||
| ==References== | ==References== | ||
Latest revision as of 19:57, 27 November 2022
Computer file format This article is about a raw disk image file format with .img filename extension. For Apple Inc.'s disk images using the .img filename extension, see Apple Disk Image. For disk images based on the ISO 9660 file system, see ISO image. For the GPS device map format, see Garmin .img. | This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "IMG" file format – news · newspapers · books · scholar · JSTOR (February 2019) (Learn how and when to remove this message) |
| Filename extensions | .img, .ima |
|---|---|
| Internet media type | application/x-ima |
IMG, in computing, refers to binary files with the .img filename extension that store raw disk images of floppy disks, hard drives, and optical discs or a bitmap image – .img.
Overview
The .img filename extension is used by disk image files, which contain raw dumps of a magnetic disk or of an optical disc. Since a raw image consists of a sector-by-sector binary copy of the source medium, the actual format of the file contents will depend on the file system of the disk from which the image was created (such as a version of FAT). Raw disk images of optical media (such as CDs and DVDs) contain a raw image of all the tracks in a disc (which can include audio, data and video tracks). In the case of CD-ROMs and DVDs, these images usually include not only the data from each sector, but the control headers and error correction fields for each sector as well.
Since IMG files hold no additional data beyond the disk contents, these files can only be automatically handled by programs that can detect their file systems. For instance, a typical raw disk image of a floppy disk begins with a FAT boot sector, which can be used to identify its file system. Disc images of optical media are usually accompanied by a descriptor file which describes the layout of the disc, and includes information such as track limits which are not stored in the raw image file.
Filename extensions and variants
The .img file extension was originally used for floppy disk raw disk images only. A similar file extension, .ima, is also used to refer to floppy disk image files by some programs. A variant of IMG, called IMZ, consists of a gzipped version of a raw floppy disk image. These files use the .imz file extension, and are commonly found in compressed images of floppy disks created by WinImage.
QEMU uses the .img file extension for raw images of hard drive disks, calling the format simply "raw".
CloneCD stores optical disc images in .img files and generates additional CloneCD Control Files (with .ccd extension) for each image to hold the necessary metadata. The CUE/BIN format stores disc images in .bin files, which are functionally equivalent to .img image files, and uses .cue files as descriptor files.
Size
The file size of a raw disk image is always a multiple of the sector size. For floppy disks and hard drives this size is typically 512 bytes (but other sizes such as 128 and 1024 exist). More precisely, the file size of a raw disk image of a magnetic disk corresponds to:
- Cylinders × Heads × (Sectors per track) × (Sector size)
E.g. for 80 cylinders (tracks) and 2 heads (sides) with 18 sectors per track:
- 80 × 2 × 18 × 512 = 1,474,560 bytes or 1440 KB
For optical discs such as CDs and DVDs, the raw sector size is usually 2,352, making the size of a raw disc image a multiple of this value.
Comparison to ISO images
ISO images are another type of optical disc image files, which commonly use the .iso file extension, but sometimes use the .img file extension as well. They are similar to the raw optical disc images, but contain only one track with computer data obtained from an optical disc. They cannot contain multiple tracks, nor audio or video tracks. They also do not contain the control headers and error correction fields of CD-ROM or DVD sectors that raw disc images usually store. Their internal format follows the structure of an optical disc file system, commonly ISO 9660 (for CDs) or UDF (for DVDs). The CUE/BIN and CCD/IMG formats, which usually contain raw disc images, can also store ISO images instead.
IMG as an image file format
.img is also a planar bitmap graphics file using simple run-length encoding, originating with Digital Research's GEM. It was commonly used on the Atari ST line of home computers, but also with some GEM-based PC software such as Corel Ventura or Timeworks Publisher.
Other disk image files
Main article: Apple Disk Image Main article: Garmin .imgIn addition, .img is an Apple Disk Image used by the Mac OS X or macOS operating system.
Garmin .img is a hard-disk image file format which contains a header and many subfiles and used to store the maps for its GPS units.
Tools
The raw IMG file format is used by several tools:
- RaWrite and WinImage use the IMG disk image format to read and write floppy disk images.
- ImDisk and Virtual Floppy Drive can mount a raw image of a floppy disk to emulate a floppy drive under Microsoft Windows.
- Nero Burning ROM supports reading IMG files for creating bootable CDs.
- mtools allows manipulation of MS-DOS floppy disk images in Unix systems.
- Programs such as dsktrans from the LibDsk suite of command-line tools (available for Linux, MS-DOS, and Microsoft Windows) will convert between different raw disk image formats.
- dd can be used in Unix to create raw disk image files of disks.
- QEMU uses IMG files as its default format for hard drive disk images.
- IrfanView with the plugin "FORMATS" (formats.dll) supports viewing GEM-IMG vector graphics.
- Garmin MapSource or GPSMapEdit can be used to read Garmin hard-disk image
.imgformat.
References
- "MIME Types - the Complete List". 15 August 2015.
- LibDsk suite of tools for accessing discs and disc image files
| Disk image file formats | |
|---|---|
| Comparison of disc image software | |
| Optical discs | |
| Hard disks | |
| Floppy disks | |
| CDDA | Disc Description Protocol |
| Convention: Any item in this table that has the form of "A+B" or "A+B+C" indicates a disk format that spans multiple files, where A contains the bulk of the data, and B and C are sidecar files. | |