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A camera raw image file contains the unprocessed data from the image sensor of a digital camera. Also called RAW (although it is not an acronym) or CCD-RAW (even for CMOS sensors), its format is proprietary and differs from one manufacturer to another, and sometimes between cameras made by one manufacturer. The image must be processed and converted to an RGB format such as TIFF or JPEG before it can be manipulated by a bitmap graphics editor, printed, or displayed by a typical web browser. A SiPix digital camera next to a matchbox to show scale. ...
The RGB color model utilizes the additive model in which red, green, and blue light are combined in various ways to create other colors. ...
This article is about TIFF, the computer image format. ...
A photo of a flower compressed with successively higher compression ratios from left to right. ...
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...
The folder of newspaper web offset printing press Printing is an industrial process for reproducing copies of texts and images, typically with ink on paper using a printing press. ...
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 charge-coupled device (CCD) is a sensor for recording images, consisting of an integrated circuit containing an array of linked, or coupled, capacitors. ...
White light is commonly described by its color temperature. ...
In color theory, saturation refers to the intensity of a specific hue. ...
In visual perception, contrast is the difference in visual properties that makes an object (or its representation in an image) distinguishable from other objects and the background. ...
- Finer control is available 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.
- Most camera raw files have a color depth of 12 bits per channel instead of the 8 used by JPEG. This allows minor exposure errors to be corrected and tonal changes to be made with less risk of posterization. (However, overexposed areas are just as white with 12 bits as with 8, so using raw is not a substitute for correct exposure.)
- Different RGB conversion algorithms can be used, not just the one coded into the camera.
Camera raw files are 2-4 times larger than JPEG files since lossless data compression is used. This avoids the compression artifacts inherent in JPEG, but means that 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). Color depth is a computer graphics term describing the number of bits used to represent the color of a single pixel in a bitmapped image or video frame buffer. ...
Posterization occurs when a region of an image with a continuous gradation of tone is replaced with several regions of fewer tones, resulting into an abrupt change from one tone to another. ...
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. ...
In computer graphics, the gamut, or color gamut, is a certain complete subset of colors. ...
The Adobe RGB color space is an RGB color space developed by Adobe Systems in 1998. ...
The title given to this article is incorrect due to technical limitations. ...
Lossless data compression is a class of data compression algorithms that allows the original data to be reconstructed exactly from the compressed data. ...
A compression artifact is a particular type of data error that is typically the result of quantization in lossy data compression. ...
Memory card for Sonys PlayStation 2 video game console. ...
Cameras that support raw files typically come with proprietary software for conversion or 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 such as Unix not supported by most commercial software. Proprietary software is a term used to describe software designed, coded, and owned by a defined person, organization or group of organizations. ...
This article needs to be cleaned up to conform to a higher standard of quality. ...
A plugin (or plug-in) is a computer program that can, or must, interact with another program to provide a certain, usually very specific, function. ...
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. ...
Unix or UNIX is a computer operating system originally developed in the 1960s and 1970s by a group of AT&T Bell Labs employees including Ken Thompson, Dennis Ritchie, and Douglas McIlroy. ...
In 2004 Adobe Systems published the Digital Negative Specification (DNG), which is intended to be a unified raw format. As of 2005, a few camera manufacturers have announced support for DNG, including Leica (native camera support) and Hasselblad (export). Other manufacturers, however, appear to have little interest making their raw files easier to read: cameras from Canon, Nikon, Sony and others include elements of encryption designed to make it harder for others to decode the format. 2004 is a leap year starting on Thursday of the Gregorian calendar. ...
In digital photography and computers, the Digital Negative Specification (DNG) is an ostensibly royalty-free raw image file format Adobe Systems announced on September 27, 2004. ...
the Leica I, 1925, 1:3,5 Leica is a camera produced by a German company of the same name. ...
Hasselblad is a Swedish manufacturer of high-quality still photography cameras based in Gothenburg, Sweden. ...
In cryptography, encryption is the process of obscuring information to make it unreadable without special knowledge. ...
Microsoft too is now including support for RAW, releasing thumbnail viewers, and it appears that they plan on embedding support into future versions of Windows.
External links
- Raw Digital Photo Decoding in Linux Dave Coffin: software to process CCD-RAW data from various models of camera.
- RAW, JPEG, and TIFF Bob Atkins: common file formats compared.
- RAW Files with a Digital Camera Why should a photographer use RAW? Advantages and disadvantages of the RAW format, as compared to JPEG.
- JPG vs RAW vs TIFF: Get it Right the First Time; Ken Rockwell's arguments against raw.
- A RAW Deal: Using the RAW image format; John Roling's explanation and arguments for the RAW format.
- Open RAW A Working Group of photographers and other people interested in advocating the open documentation of digital camera RAW files.
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