A raw image file contains minimally processed data from the image sensor of a digital camera or image scanner. They are often incorrectly refered to as RAW image files. There currently is not one RAW specification. Raw files are so named because they are not yet processed and ready to be used with a bitmap graphics editor or printed. Normally, the image will be processed by a raw converter in a wide-gamut internal colorspace where precise adjustments can be made before conversion to an RGB file format such as TIFF or JPEG for storage, printing, or further manipulation. A filename extension is a suffix to the name of a computer file applied to show its format. ... Fujifilm Holdings Corporation or Fujifilm ) is a Japanese company known for its photographic film and cameras. ... Canon Inc. ... Eastman Kodak Company (NYSE: EK) is a large multinational public company producing photographic equipment. ... Minolta was a Japanese worldwide manufacturer of cameras, camera accessories, photo-copiers, fax machines and laser printers. ... For other uses, see Nikon (disambiguation). ... This article refers to a Japanese camera maker. ... Adobe Systems (pronounced a-DOE-bee IPA: ) (NASDAQ: ADBE) (LSE: ABS) is an American computer software company headquartered in San Jose, California, USA. Adobe was founded in December 1982[1] by John Warnock and Charles Geschke, who established the company after leaving Xerox PARC in order to develop and sell... Pentax Corporation ) (TYO: 7750 ) is a Japanese company founded in 1919 as Asahi Optical Joint Stock Co. ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... Sigma Corporation ) is a Japanese company manufacturing cameras, lenses, flashes and other photographic accessories. ... A four colour Epson Stylus C45 inkjet printer Epson is one of the worlds largest manufacturers of inkjet, dot-matrix and laser printers, scanners, desktop computers, business, multimedia and home theatre projectors, point of sale docket printers and cash registers, laptops, integrated circuits, LCD components and other associated electronic... Mamiya C330 twin-lens reflex camera Mamiya 645 Super Mamiya RZ67 Pro I 35mm SLR Mamiya ZE Mamiya-OP Co. ... Panasonic is an international brand name for Japanese electric products manufacturer Matsushita Electric Industrial Co. ... RED Digital Camera Company is a developer of a digital video camera called Red One which the company says will be capable of recording resolutions up to 4520 x 2540 via a sensor large enough to adapt to standard 35mm lenses normally used by film cameras. ... Image file formats provide a standardized method of organizing and storing image data. ... Look up digital camera in Wiktionary, the free dictionary. ... In computing, a scanner is a device that analyzes images, printed text, or handwriting, or an object (such as an ornament) and converts it to a digital image. ... A bitmap graphics editor is a computer program that allows users to paint and edit pictures interactively on the computer screen and save them in one of many popular bitmap or raster formats such as JPEG, PNG, GIF and TIFF. Usually an image viewer is preferred over a bitmap graphics... For other uses, see Print. ... In color reproduction, including computer graphics and photography, the gamut, or color gamut (pronounced ), is a certain complete subset of colors. ... A color model is an abstract mathematical model describing the way colors can be represented as tuples of numbers, typically as three or four values or color components (e. ... REDIRECT RGB color model ... This article is about TIFF, the computer image format. ... JPG redirects here. ...

Raw image files are sometimes called digital negatives, as they fulfill the same role as film negatives in traditional chemical photography: that is, the negative is not directly usable as an image, but has all of the information needed to create an image. In addition to raw files from cameras, raw data from film scanners can also be referred to as digital negatives. Color, positive picture (A) and negative (B), monochrome positive picture (C) and negative (D) In photography, a negative may refer to 3 different things, although they are all related. ...

Like a photographic negative, a digital negative may have a wider dynamic range or color gamut than the eventual final image format. The selection of the final choice of image rendering is part of the process of white balancing and color grading. White light is commonly described by its color temperature. ... Color grading is the process of altering and enhancing the color of a motion picture or television image, either electronically, photo-chemically or digitally. ...

File contents

Providing a detailed and concise description of the content of raw files is highly problematic. There is no single raw format: they can be similar or radically different. Different manufacturers use their own proprietary and typically undocumented formats, which are collectively known as raw format. Often they also change the format from one model to the next. At least one manufacturer encrypts portions of the file. This industry-wide situation has engendered concern that in the future many very valuable raw photos may be rendered unopenable as operating systems and applications move forward and abandoned raw formats are dropped from new software. Ultimately any raw format's purpose is to faithfully record both 100% of exactly what the sensor "saw" (the data) and the conditions surrounding the recording of the image (the metadata). Encrypt redirects here. ... Metadata is data about data. ...

Digital camera raw files contain the pixel data from a rectangular image sensor, the modern equivalent of traditional film, usually at 12 or 14 bits per sensor bucket. The sensor is almost invariably overlaid with a so-called Bayer filter, consisting of a mosaic of red, blue and green filters in alternating rows of RG and GB. Given that three colors fit uncomfortably in a rectangular grid, green was chosen to be doubly present, since the human eye is more sensitive to it. Green also often serves as the luminance channel, and as the dominant channel for in-camera black-and-white conversions. To retrieve an image from a raw file, this mosaic of data must be converted into a full RGB image. This is known as demosaicing, but is sometimes referred to as digital development. This article is about the picture element. ... This article or section does not cite its references or sources. ... The Bayer arrangement of color filters on the pixel array of an image sensor Front page of Dr. Bryce Bayers 1976 patent on the Bayer pattern filter mosaic, showing his terminology of luminance-sensitive and chrominance-sensitive elements A Bayer filter mosaic is a color filter array (CFA) for... Black-and-white or black and white) can refer to a general term used in photography, film, and other media (see black-and-white). ... A demosaicing algorithm is a digital image process used to interpolate a complete image from the partial raw data received from the color-filtered image sensor internal to many digital cameras in form of a matrix of colored pixels. ...

One variation on the Bayer scheme is the RGBE sensor of the Sony DSC-F828, which experimented with exchanging the green in the RG rows with Emerald (cyan). Other sensors, such as the Foveon X3 sensor capture information directly in RGB form, having three pixel sensors in each location, one for each colour component; these camera RGB raw data still need to be processed to make an image file. Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... Cyan (from Greek κυανοs, meaning blue) may be used as the name of any of a number of a range of colors in the blue/green part of the spectrum. ... The Foveon X3 sensor is an image sensor for digital cameras produced by Foveon, Inc. ... A high-tech CMOS imager, mainly developed for medical imaging. ...

Flatbed and film scanner sensors are typically straight narrow RGB or RGBI (where "I" is infrared) strips that are swept across an image; other than that, the remainder of the discussion about raw files applies to them as well. (Some scanners do not allow the user access to the raw data at all, as a speed compromise. The raw data is processed very rapidly inside the scanner to select out the best part of the available dynamic range so only the result is passed to the computer for permanent storage.)

The contents of raw files include more information, and potentially higher quality, than the converted results, in which the rendering parameters are fixed, the color gamut is clipped, and there may be quantization and compression artifacts. Each pixel in a raw file has a greater bit-depth (compared to typical 8-bit renderings), and can thus store more subtle variations and range in color and detail. Hence, large transformations of the data, such as increasing the exposure of a dramatically under-exposed photo, result in less visible artifacts when done from raw data than when done from already rendered image files. Raw data leaves more scope for both corrections and artistic manipulations, without resulting in images with visible flaws such as posterization. Quantization, involved in image processing. ... Image compression is the application of Data compression on digital images. ... An example of a photo in JPEG format (24bit colour or 16. ...

The generally-accepted standard for digital negatives in the digital cinema industry is the SMPTE DPX format. The Society of Motion Picture and Television Engineers or SMPTE (pronounced simptee or sometimes sumptee) is a US professional association of engineers. ... DPX, the short form of Digital Picture Exchange, is a common file format for digital film work and is an ANSI/SMPTE standard (268M-2003). ...

Benefits

Nearly all digital cameras can process the image from the sensor into a JPEG file using settings for white balance, color saturation, contrast, and sharpness that are either selected automatically or entered by the photographer before taking the picture. Cameras that support raw files save these settings in the file, but defer the processing. This results in an extra step for the photographer, so raw is normally only used when additional computer processing is intended. However, raw permits much greater control than JPEG for several reasons: A specially developed CCD used for ultraviolet imaging in a wire bonded package. ... White light is commonly described by its color temperature. ... It has been suggested that this article or section be merged with Chromaticity. ... Left side of the image has low contrast, the right has higher contrast. ... Screen Capture of Adobe Photoshops Unsharp Mask Filter. ...

• Finer control is easier for the settings when a mouse and keyboard are available to set them. For example, the white point can be set to any value, not just discrete values like "daylight" or "incandescent".
• The settings can be previewed and tweaked to obtain the best quality image or desired effect. (With in-camera processing, the values must be set before the exposure). This is especially pertinent to the white balance setting since color casts can be difficult to correct after the conversion to RGB is done.
• Camera raw files have 12 or 14 bits of intensity information, not the gamma-compressed 8 bits typically stored in processed TIFF and JPEG files; since the data are not yet rendered and clipped to a color space gamut, more precision may be available in highlights, shadows, and saturated colors.
• The working color space can be set to whatever is desired.
• Different demosaicing algorithms can be used, not just the one coded into the camera.

Example of CRT gamma correction Plot of the sRGB standard gamma-expansion nonlinearity (red), and its local gamma value, slope in log–log space (blue). ... This article is about TIFF, the computer image format. ... JPG redirects here. ... A comparison of different color spaces. ... In color reproduction, including computer graphics and photography, the gamut, or color gamut (pronounced ), is a certain complete subset of colors. ... A comparison of different color spaces. ... A demosaicing algorithm is a digital image process used to interpolate a complete image from the partial raw data received from the color-filtered image sensor internal to many digital cameras in form of a matrix of colored pixels. ...

Drawbacks

Camera raw files are typically 2–6 times larger than JPEG files. Some raw formats do not use compression, some implement lossless data compression to reduce the size of the files without affecting image quality and others use lossy data compression where quantization and filtering is performed on the image data. While use of raw formats avoids the compression artifacts inherent in JPEG, fewer images can fit on a given memory card. It also takes longer for the camera to write raw images to the card, so fewer pictures can be taken in quick succession (affecting the ability to take, for example, a sports sequence). Lossless data compression is a class of data compression algorithms that allows the exact original data to be reconstructed from the compressed data. ... A lossy data compression method is one where compressing data and then decompressing it retrieves data that may well be different from the original, but is close enough to be useful in some way. ... A compression artifact is a particular type of data error that is typically the result of quantization in lossy data compression. ... Four major types of memory cards (from left to right: CompactFlash, Memory Stick, Secure Digital, and xD. A memory card or flash memory card is a solid-state electronic flash memory data storage device used with digital cameras, handheld and Mobile computers, telephones, music players, video game consoles, and other...

There is still no widely accepted standard raw format. Adobe's Digital Negative (DNG) format has been put forward as a standard, but has not been adopted by major camera companies. Numerous different raw formats are currently in use and new raw formats keep being developed while others are orphaned. Adobe Systems (pronounced a-DOE-bee IPA: ) (NASDAQ: ADBE) (LSE: ABS) is an American computer software company headquartered in San Jose, California, USA. Adobe was founded in December 1982[1] by John Warnock and Charles Geschke, who established the company after leaving Xerox PARC in order to develop and sell... In digital photography, the Digital Negative (DNG) file format is an ostensibly royalty free raw image format designed by Adobe Systems. ...

Because of the lack of a standard raw format, more specialized software may be required to open raw files than for standardized formats like JPEG or TIFF. Software developers are also having to frequently update their products to support the raw formats of the latest cameras.

The time taken in the image workflow is an important factor when choosing between raw and ready-to-use image formats.

Software support

Cameras that support raw files typically come with proprietary software for conversion of their raw format to TIFF or JPEG. Other 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. A portable open source program, dcraw, supports most raw formats and can be made to run on operating systems not supported by most commercial software (such as Unix). Proprietary software is software with restrictions on copying and modifying as enforced by the proprietor. ... A computer program is a collection of instructions that describe a task, or set of tasks, to be carried out by a computer. ... For other uses, see Plug in. ... Reverse engineering (RE) is the process of taking something (a device, an electrical component, a software program, etc. ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... dcraw is an open source, ANSI C computer program written by Dave Coffin. ... Filiation of Unix and Unix-like systems Unix (officially trademarked as UNIX®, sometimes also written as or ® with small caps) is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy. ...

Raw file formats are proprietary, and differ greatly from one manufacturer to another, and sometimes between cameras made by one manufacturer. In 2004 Adobe Systems published the Digital Negative Specification (DNG), which is intended to be a unified raw format. Adobe Photoshop CS2 and CS3 contain extensive support of RAW as does Adobe Photoshop Lightroom. As of 2006, several camera manufacturers have started to announce support for DNG in newer camera models, including Leica, Samsung, Ricoh, Pentax (native camera support) and Hasselblad (export). The Leica Digital-Modul-R (DMR) was first to use DNG as its native format. Year 2004 (MMIV) was a leap year starting on Thursday of the Gregorian calendar. ... Adobe Systems (pronounced a-DOE-bee IPA: ) (NASDAQ: ADBE) (LSE: ABS) is an American computer software company headquartered in San Jose, California, USA. Adobe was founded in December 1982[1] by John Warnock and Charles Geschke, who established the company after leaving Xerox PARC in order to develop and sell... Adobe announced the Specification in 2004. ... Photoshop redirects here. ... Adobe Photoshop Lightroom is a photography software program developed by Adobe Systems for Mac OS X and Microsoft Windows, designed to assist professional photographers in managing thousands of digital images and doing post production work. ... 2006 is a common year starting on Sunday of the Gregorian calendar. ... Leica is the name of several cameras produced by a German company of the same name. ... Samsung Group is one of the largest South Korean business groupings. ... Ricoh Company, Ltd. ... Pentax Corporation ) (TYO: 7750 ) is a Japanese company founded in 1919 as Asahi Optical Joint Stock Co. ... This article is about Victor Hasselblad AB, the Swedish company. ...

Microsoft's Digital Image 2006 was able to recognize and organize raw image formats such as .crw, .cr2, and .nef, which are file formats produced by Canon and Nikon,^{[citation needed]} but that product was discontinued in 2007.^[1] For Windows XP, there is a free download available that integrates viewing and printing into other included photo tools, but it is not supported by Microsoft.^[2] Also, Windows Photo Gallery and Windows Live Photo Gallery can view any raw image format if the necessary WIC codecs are installed. Camera manufacturers Canon, Nikon, Sony, Olympus and Pentax have released WIC codecs. ^[3] A commercial DNG codec is also available from Ardfry Imaging. ^[4] These applications however only open raw images when double-clicked. They do not automatically associate with the raw file extensions. Microsoft Corporation, (NASDAQ: MSFT, HKSE: 4338) is a multinational computer technology corporation with global annual revenue of US$44. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... Canon Inc. ... For other uses, see Nikon (disambiguation). ... Windows XP is a line of operating systems developed by Microsoft for use on general-purpose computer systems, including home and business desktops, notebook computers, and media centers. ... Windows Photo Gallery (WPG) is an application included with Microsofts Windows Vista operating system that provides photo management and basic editing facilities. ... Windows Live Photo Gallery is a photo management and sharing application to be released as a part of Microsofts Windows Live intitiative. ... The Windows Imaging Component (WIC) is a Component Object Model based imaging codec framework introduced in Windows Vista for working with and processing digital images and image metadata. ... Canon Inc. ... For other uses, see Nikon (disambiguation). ... Sony Corporation ) is a Japanese multinational corporation and one of the worlds largest media conglomerates with revenue of $66. ... This article refers to a Japanese camera maker. ... Pentax Corporation ) (TYO: 7750 ) is a Japanese company founded in 1919 as Asahi Optical Joint Stock Co. ... In digital photography, the Digital Negative (DNG) file format is an ostensibly royalty free raw image format designed by Adobe Systems. ...

In 2005, Apple Computer introduced several products which offered raw file support. In January, Apple released iPhoto 5, which offered basic support for viewing and editing raw files. In April, Apple introduced a new version of its operating system, Mac OS X v10.4, which added raw support directly to the operating system, as part of the ImageIO framework, which adds raw support automatically to the majority of Mac OS X applications both from Apple (such as Preview, Mac OS X'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 OS X generally include updated support for new RAW file formats introduced in the intervening months by camera makers. Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ... Apple Inc. ... iPhoto is a software application made by Apple Inc. ... Mac OS X version 10. ... Aperture is a software program for Mac OS X announced by Apple Computer on October 19th, 2005, designed to assist professional photographers in post-production work. ...

There are many other "raw workflow applications" designed to provide efficient processing and post-processing of raw images, including Helicon Filter, Phase One's Capture One and Bibble Labs' Bibble Pro. Like Apple Aperture, Adobe Photoshop and Adobe Photoshop Lightroom, these programs provide sophisticated controls for processing the information stored in the Raw file and converting raw files to JPEG or TIFF. Picasa, a free image editing and cataloguing program from Google, can read and display many raw formats, but like iPhoto, Picasa provides only limited tools for processing the data in a raw file. Helicon Filter, often referred to as Helicon or as Filter, is a proprietary commercial and freeware photo editing software program for Microsoft Windows, similar to such programs as Adobe Photoshop and the open source GIMP, developed and published by Helicon Soft Ltd. ... Photoshop redirects here. ... Adobe Photoshop Lightroom is a photography software program developed by Adobe Systems for Mac OS X and Microsoft Windows, designed to assist professional photographers in managing thousands of digital images and doing post production work. ... Picasa is a software application for organizing and editing digital photos, originally created by Idealab and now owned by Google. ... This article is about the corporation. ...

UFRaw is free software based on dcraw. It can be used as a GIMP plugin and is available for most operating systems. The Unidentified Flying Raw (UFRaw) is a stand-alone utility or Gimp-plugin to read and manipulate images in RAW image formats format from digital cameras. ... For other uses, see Gimp (disambiguation). ...

RawShooter Essentials 2005/6 was free software developed by Pixmantec. In 2006 Adobe Systems Inc acquired the assets of Pixmantec ApS. RawShooter Essentials is no longer being updated (The last update added support for the Canon 5D and the Nikon D200). It could still be downloaded as a free product until Adobe's Photoshop Lightroom 1.0 was released in March 2007. The software was fully featured, including wide support for various raw formats, file priority sorting and batch processing. Light Crafts' LightZone photo editing software provides the ability to edit RAW natively. Most tools are "raw converters," but LightZone allows a user to edit RAW just as if it were TIFF or JPEG. Renewal of the surface coating of an adobe wall in Chamisal, New Mexico Adobe is a natural building material composed of sand, sandy clay and straw or other organic materials, which is shaped into bricks using wooden frames and dried in the sun. ... The EOS 5D is a 12. ... The Nikon D200 is a semi-professional digital SLR camera. ... Adobe Systems (pronounced a-DOE-bee IPA: ) (NASDAQ: ADBE) (LSE: ABS) is an American computer software company headquartered in San Jose, California, USA. Adobe was founded in December 1982[1] by John Warnock and Charles Geschke, who established the company after leaving Xerox PARC in order to develop and sell... Adobe Photoshop Lightroom is a photography software program developed by Adobe Systems for Mac OS X and Microsoft Windows, designed to assist professional photographers in managing thousands of digital images and doing post production work. ...

Processing

There is no single standard algorithm for converting data from a Bayer filter or Foveon sensor into RGB format; a number of different algorithms have been proposed, and some have been patented in the USA. Different programs may give slightly different results, better or worse subjectively, for any particular image. The Bayer arrangement of color filters on the pixel array of an image sensor Front page of Dr. Bryce Bayers 1976 patent on the Bayer pattern filter mosaic, showing his terminology of luminance-sensitive and chrominance-sensitive elements A Bayer filter mosaic is a color filter array (CFA) for... Foveon, Inc. ...

Although the term "raw" describes files in the classical sense of "raw data" vs. "cooked data", raw files typically are slightly processed in the camera. In general, this processing is limited to algorithms that require direct access to the camera's hardware. This includes "long exposure noise reduction" (aka “dark frame subtraction”) and the mapping out of "hot" (too bright) or "dead" (too dim) pixels. Also information about standard processing parameters are stored in the file (so a Raw converter can generate the same JPEG file as the camera would create). In digital photography, dark frame subtraction is a way to minimize image noise. ... A stuck pixel is a common pixel defect on LCD screens. ... Close-up of an LCD display, showing a dead green subpixel A dead pixel is a defective pixel that remains unlit on an LCD screen or a CCD or CMOS sensor in a digital camera. ...

Some newer Raw formats also allow nonlinear quantization. This better allows to compress the raw data without visible degradation of the image by removing invisible and irrelevant information from the image. Although noise is discarded this has nothing to do with (visible) noise reduction.

References

1. ^ http://www.microsoft.com/products/imaging/default.mspx
2. ^ http://www.microsoft.com/windowsxp/using/digitalphotography/prophoto/raw.mspx
3. ^ Understanding RAW Image Support in Windows Vista: Windows Vista team blog
4. ^ DNG Thumbnail and Preview Support for Windows Photo Gallery and Windows Live Photo Gallery

See also

• Image file formats
• dcraw
• List of cameras supporting a raw format

Image file formats provide a standardized method of organizing and storing image data. ... dcraw is an open source, ANSI C computer program written by Dave Coffin. ... This is an incomplete list, which may never be able to satisfy certain standards for completeness. ...

External links

• Open RAW A working group of photographers and other people interested in advocating the open documentation of digital camera raw files
• Adobe: Understanding Raw Files(PDF); Background on how camera sensors treat raw files
• DCraw Raw Digital Photo Decoding in Linux Dave Coffin: software to process RAW data from various models of camera. Also shows all current cameras that support RAW. (supported models)
• libopenraw, an ongoing effort to provide a free software implementation for camera RAW files decoding.
• jrawio: An Open Source Java library for reading camera raw files from various digital camera models.
• RAW Data 48 bit RAW data processing (High Dynamic Range Imaging)
• Sample RAW files
• Pixmantec ApS Home of RawShooter Essentials, a RAW batch converter. The software is no longer available from this site since Adobe bought Pixmantec in 2006.
• Nikon Capture NX A Trial version of Nikon's raw processing software.
• Adobe Lightroom
• Raw Therapee (THe Experimental RAw Photo Editor) is a free RAW converter and digital photo processing software.
• Light Crafts' LightZone Free Trial version of Light Crafts' Photo Editing Software that allows you to edit RAW natively.
• RoboImport camera downloader software that performs batch conversion from RAW to Adobe DNG format

Photographers' views

• Bob Atkins: Raw, JPEG, and TIFF; common file formats compared.
• Sean T. McHugh: RAW Files with a Digital Camera; Why should a photographer use raw? Advantages and disadvantages of raw formats, as compared to JPEG
• John Roling: A RAW Deal: Using the RAW image format; explanation and arguments for raw formats.
• Jim M. Goldstein: RAW vs JPEG: Is Shooting RAW Format For Me?