Форматы RAW-изображений: от сенсора к готовому снимку.

File format used in digital photography

the Shockwave Media File (. dcr) created with Adobe Director

A camera raw image file contains unprocessed or minimally processed data from the image sensor of either a digital camera, a motion picture film scanner, or other image scanner. Raw files are so named because they are not yet processed, and contain large amounts of potentially redundant data. Normally, the image is processed by a raw converter, in a wide gamut internal color space where precise adjustments can be made before conversion to a viewable file format such as JPEG or PNG for storage, printing, or further manipulation. There are dozens of raw formats in use by different manufacturers of digital image capture equipment.

Raw image files are sometimes incorrectly described as "digital negatives". Rather, the raw datasets are more like exposed but undeveloped film which can be converted (electronically developed) in a non destructive manner multiple times in observable, reversible steps to reach a visually desired image. (With exposed film, development is a single event that physically transforms the unexposed film irreversibly.) Like undeveloped photographic film, a raw digital image may have a wider dynamic range or color gamut than the developed film or print. Unlike physical film after development, the Raw file preserves the information captured at the time of exposure. The purpose of raw image formats is to save, with minimum loss of information, data obtained from the sensor. Raw image formats are intended to capture the radiometric characteristics of the scene, that is, physical information about the light intensity and color of the scene, at the best of the camera sensor's performance. Most raw image file formats store information sensed according to the geometry of the sensor's individual photo receptive elements (sometimes called pixels) rather than points in the expected final image: sensors with hexagonal element displacement, for example, record information for each of their hexagonally displaced cells, which a decoding software will eventually transform into the rectangular geometry during "digital developing".

Panasonic's raw converter corrects geometric distortion and chromatic aberration on such cameras as the LX3, with necessary correction information presumably included in the raw. Phase One's raw converter Capture One also offers corrections for geometrical distortion, chromatic aberration, purple fringing and keystone correction emulating the shift capability of tilt shift in software and specially designed hardware, on most raw files from over 100 different cameras. The same holds for Canon's DPP application, at least for all more expensive cameras like all EOS DSLRs and the G series of compact cameras. To obtain an image from a raw file, this mosaic of data must be converted into standard RGB form. This is often referred to as "raw development". When converting from the four sensor 2x2 Bayer matrix raw form into RGB pixels, each pixel only contains partial colour data and so the remaining colour data is interpolated from the surrounding pixels. There are several algorithms used to achieve this. Simple algorithms such as linear interpolation result in colour artifacts and blurring. If raw format data is available, it can be used in high dynamic range imaging conversion, as a simpler alternative to the multi exposure HDI approach of capturing three separate images, one underexposed, one correct and one overexposed, and "overlaying" one on top of the other.

Cameras that support raw files typically come with proprietary software for conversion of their raw image data into standard RGB images. Other processing and conversion programs and plugins are available from vendors that have either licensed the technology from the camera manufacturer or reverse engineered the particular raw format and provided their own processing algorithms.

In January 2005, Apple released iPhoto 5, which offered basic support for viewing and editing many raw file formats. In April 2005, Apple's OS X 10.4 brought raw support to the operating system's ImageIO framework, enabling raw support automatically in the majority of macOS applications both from Apple (such as Preview, macOS's PDF and image viewing application, and Aperture, a photo post production software package for professionals) as well as all third party applications which make use of the ImageIO frameworks. Semi regular updates to macOS generally include updated support for new raw formats introduced in the intervening months by camera manufacturers. In 2016, Apple announced that iOS 10 would allow capturing raw images on selected hardware, and third party applications will be able to edit raw images through the operating system's Core Image framework. In 2020, Apple released the iPhone 12 Pro and iPhone 12 Pro Max. Both of these devices support Apple ProRAW (as of iOS 16.0.3). ProRAW photos are 12 bit DNG files.

Microsoft supplies the free Windows Camera Codec Pack for Windows XP and later versions of Microsoft Windows, to integrate raw file viewing and printing into some Microsoft Windows tools. The codecs allow native viewing of raw files from a variety of specific cameras in Windows Explorer / File Explorer and Windows Live Photo Gallery / Windows Photo Gallery, in Windows Vista and Windows 7. As of October 2016, Microsoft had not released an updated version since April 2014, which supported some specific cameras by the following manufacturers: Canon, Casio, Epson, Fujifilm, Kodak, Konica Minolta, Leica, Nikon, Olympus, Panasonic, Pentax, Samsung, and Sony. For windows 10 this was essentially replaced in 2019 by Microsoft Raw Image Extension. The Extension allows native viewing of raw files from many mid to high end digital cameras in Windows Explorer / File Explorer and Microsoft Photos.

Microsoft Windows supports the Windows Imaging Component (WIC) codec standard. WIC was available as a stand alone downloadable program for Windows XP Service Pack 2, and built into Windows XP Service Pack 3, Windows Vista, and later versions. Windows Explorer / File Explorer, and Windows Live Photo Gallery / Windows Photo Gallery can view raw formats for which the necessary WIC codecs are installed. Canon, Nikon, Sony, Olympus and Pentax have released WIC codecs for their cameras, although some manufactures only provide codec support for the 32 bit versions of Microsoft Windows. Commercial DNG WIC codecs are also available from Ardfry Imaging, and others; and FastPictureViewer Professional installs a set of WIC enabled image decoders.

Android Lollipop 5.0, introduced in late 2014, can allow smartphones to take raw images, useful in low light situations.

darktable is a raw workflow tool for macOS, Microsoft Windows, Linux and other open Unix like operating systems. The software features native 32 bit floating point processing and a plugin architecture. dcraw is a program which reads most raw formats and can be made to run on operating systems not supported by most commercial software (such as Unix). LibRaw is an API library based on dcraw, offering a more convenient interface for reading and converting raw files. HDR PhotoStudio and AZImage are some of the commercial applications that use Libraw. Jrawio is another API library, written in pure Java code and compliant to the standard Java Image I/O API. digiKam is an advanced digital photo management application for Linux, Microsoft Windows, and Mac OS X that supports raw processing. ExifTool supports the reading, writing and editing of metadata in raw image files. ExifTool supports many different types of metadata including Exif, GPS, IPTC, XMP, JFIF, GeoTIFF, ICC Profile, Photoshop IRB, FlashPix, AFCP and ID3, as well as the maker notes of many digital cameras. ImageMagick, a software suite for image manipulation and conversion, reads many different raw file formats. ImageMagick is available for Linux/Unix, Mac OS, Microsoft Windows, and other platforms. LightZone is a photo editing program providing the ability to edit many raw formats natively. Most tools are raw converters, but LightZone allows a user to edit a raw file as if it were TIFF or JPEG. The project was discontinued in September 2011 and reinstated as an open source project in December 2012. Rawstudio is a raw format developer. RawTherapee is a raw developer supporting Linux, OS X and Microsoft Windows operating systems. It features a native 32 bit floating point pipeline. Shotwell is an image organizer available for all major operating systems with the ability to view and edit raw images and has built in social networking upload capability. UFRaw is a frontend which uses dcraw as a back end. It can be used as a GIMP plugin and is available for most operating systems.

In addition to those listed under operating system support, above, the commercial software described below support raw formats.

.3fr (Hasselblad)
ari (Arri Alexa)
arw srf sr2 (Sony)
bay (Casio)
braw (Blackmagic Design)
cri (Cintel)
crw cr2 cr3 (Canon)
cap iiq eip (Phase One)
dcs dcr drf k25 kdc (Kodak)
dng (Adobe)
erf (Epson)
fff (Imacon/Hasselblad raw)
gpr (GoPro)
jxs (JPEG XS Bayer profile)
mef (Mamiya)
mdc (Minolta, Agfa)
mos (Leaf)
mrw (Minolta, Konica Minolta)
nef nrw (Nikon)
orf (Olympus)
pef ptx (Pentax)
pxn (Logitech)
R3D (RED Digital Cinema)
raf (Fuji)
raw rw2 (Panasonic)
raw rwl dng (Leica)
rwz (Rawzor)
srw (Samsung)
tco (intoPIX)
x3f (Sigma)

Less commonly, raw may also refer to a generic image file format containing only pixel color values. For example, "Photoshop Raw" files (. raw) contain a pure array of bytes top to bottom, left to right pixel order. Dimensions must be input manually when such files are re opened, or a square image is assumed. Also the channel size and bit depth per channel has to be provided when opening this format, as the ambiguities of whether the bytes are to be decoded as single channels at high precision, or multiple channels at lower precision, is not determinable from the byte array itself. Due to its simplicity, this format is very open and compatible, though limited by its lack of metadata and run length encoding. Especially in photography and graphic design, where color management and extended gamuts are important, and large images are common.