Pixel
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A pixel is generally thought of as the smallest single component of a digital image. The definition is highly context-sensitive.
Pixel
A contraction of the words picture element. The smallest unit of information in a raster based format. A grid cell.
Point ...
Pixel- Pixel element. The smallest resolution unit (NCRST).
Platform - Where a sensor is based, i.e., a satellite, aircraft, or other flying object (NCRST).
Pixel: One picture element. Often used synonymously with a raster or grid cell. The smallest discrete element which makes up an image.
Planimetric: In mapping, refers to spatial data that do not include topographic or relief data.
pixel -- two-dimensional picture element that is the smallest nondivisible element of a digital image.
Pixel or cell? All raster datasets are stored in similar formats. You will want to know the difference between a pixel and a cell, even though they are functionally equivalent.
Pixel
A single display element on an LCD screen. The more pixels, the higher the resolution and definition.
Position
An exact, unique location based on a geographic coordinate system.
Pixel One picture element of a uniform raster or grid file. Often used synonymously with cell.
pixel. picture element; a tiny dot in a digital image composed of a set of such dots
PNG. see “portable network graphic (PNG)' ...
Pixel: Abbreviation for Picture Element, the smallest nondivisible image-forming unit of a plot or video display. Each cell can have assigned attributes, in addition to color.
A pixel is Worth 1,000 Words... or $100!
This spotlight takes a look at the design process involved in using digital data to feature a map of Canada on the new $100 bill.
PIXELTYPE SIGNEDINT
HDF
The import of HDF bands requires the specification of the individual bands as seen by GDAL: ...
PIXEL
1) The smallest element of a display device, such as a video monitor, that can be independently assigned attribute, such as colour and intensity. 2) In remote sensing, refers to the fundamental unit of data collection.
Pixel - A term derived from "picture element", which is the smallest unit of resolution in data storage and display.
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Megapixel Imaging Technology
MITES
Miniature Interferometer Terminals for Earth Survey ...
each pixel or cell is assumed to have only one value
this is often inaccurate - the boundary of two soil types may run across the middle of a pixel ...
Some pixels were not classified into any erosion class. This because the training area does not always describe all elements of the landscape present across the entire study area.
After pixel classification into five colors.
A mask created to separate text and other objects.
After subtraction of the mask.
A "mixed pixel" results from the fact that individual areas, consisting of different features or classes may be below (smaller than) the resolution of the sensor. Consider this hypothetical "map" of a rural setting ...
See Also: pixel
[graphics (computing)] A three-dimensional pixel used to display and rotate three-dimensional images.
4. Image/Image Pixel Tool/Map Pixel Value uses a range defined by a minimum and maximum gray level value or estimates a selected region. This function can be used to easily convert a range of pixel colors to a single color for processing.
Digital Number (DN) In image processing, the value of each pixel in a dataset. Usually these values are 8-bit, that is ranging from 0-255.
(Topology of topography) pixel p. 29 smallest resolvable unit in an image; an area (usually rectangular) forming a part of a systematic, uniform division of a study area. Contraction of picture element. planar graph p.
A GIS database includes data about the spatial location and shape of geographic features recorded as points, lines, areas, pixels, grid cells, or tins, as well as their attributes.
pixels. implementation A software package that conforms to a standard or specification. A specific instance of a more generally defined system.
A raster display builds an image from pixels, small square picture elements of coarse or fine resolution. A raster database maintains a "picture" of reality in which each cell records some sort of information averaged over the cell`s area.
Raster Data: An abstraction of the real world where spatial data is expressed as a matrix of cells or pixels, with spatial position implicit in the ordering of the pixels.
A pixel is the basic unit of measurement in computer screen resolution and is also, the smallest unit constituting a bitmap (raster) image.
Each band consists of an array of pixels (cells), and each pixel has a value (e.g., a Landsat satellite image). Raster datasets can be stored in many formats, including TIFF, ERDAS Imagine, Esri Grid, and MrSID.
Relationship Class ...
For example an aerial photograph may need to be stretched (orthorectified) using photogrammetry so that its pixels align with longitude and latitude gradations (or whatever grid is needed).
In unsupervised training, a clustering algorithm is used to partition a sample of the data into populations of pixels with similar reflectance, ...
0 PRODUCTION_DATE 1997 9 15 RASTER_ORDER LEFT_RIGHT/TOP_BOTTOM BAND_ORGANIZATION "SINGLE FILE" BAND_CONTENT BLACK&WHITE BITS_PER_PIXEL 8 SAMPLES_AND_LINES 6221 7601 HORIZONTAL_DATUM NAD83 HORIZONTAL_COORDINATE_SYSTEM UTM COORDINATE_ZONE 10 ...
Take a look at the output results of the Slope analysis, again make sure to use the identify features tool to explore the pixel values of light and dark areas.
Each pixel you see measures 10x10 meters. The viewport is centered on X=359180, Y=256890 (Rhode Island State Plane Feet, NAD83).
It is easier to draw on the screen and on computer devices that display pixels. It also works better with constant variation in the data like elevation. There are two major drawbacks to raster.
Raster data is characterized by pixel values. Basically, a raster file is a giant table, where each pixel is assigned a specific value from 0 to 255.
In contrast, the "raster" or "grid-based" format generalizes map features as cells or pixels in a grid matrix (figure 3.3). The space is defined by a matrix of points or cells, organized into rows and columns.
Raster references spatial data using a grid of cells (or pixels) , whereas vector data references spatial data using a series of coordinates.
In the last level, pixels are also squares with horizontal and vertical diagonals; this unorthodox orientation may be fixed by the artifice of rotating the entire map by 45 degrees.
For example, a raster image is composed of thousands of 'pixels' (picture elements) that are analogous to the dots on a computer screen.
At a minimum frame rate of 15 frames per second, and a low resolution of 320 by 240 pixels, passive 3D animations in AVI or MOV formats require disk space of many megabytes.
enlarge the same map without enlarging the pixels, hence show more detail ...
pix] is the camera frame to pixel frame transformation matrix made up of calibration parameters, [s.sup.c] is the line of sight vector from the camera to the target expressed in the camera frame, [C.sub.n.sup.b] and [C.sub.b.sup.
Radiometric Resolution: Ikonos data is collected as 11 bits per pixel (2048 gray tones). This means that there is more definition in the grey scale values and as a viewer you can see more detail in an image.
raster Data displayed as discrete picture elements (pixels).
relate An operation that establishes a temporary connection between corresponding records in two tables using an item common to both.
Consider two rectangular regions on a view, one of 100 X 100 pixels, the other of 101 X 101 pixels. Both could be equally good approximations to a rectangular feature; they differ by only one pixel (one percent) in either dimension.
A measure of the accuracy or detail of a graphic display, expressed as dots per inch, pixels per line, lines per millimeter, etc. It is a measure of how fine an image is, usually expressed in dots per inch (dpi).
Tools such as these can manipulate output from high (over 3000 pixels per inch) resolution drum scanners, as well as the output from a desktop flatbed scanner.
You can also see binary data at any zoom level, letting you work productively down to the pixel level. Users can move seamlessly between raster and vector editing in MicroStation.
Raw images are built up by a rectangular array of pixels with variable values, but these pixels don't have a correct geometric position yet.
Each pixel can indicate a type of land cover, such as wetlands, forests, pastures, and developed areas. Such technology is now being used to monitor gains and losses in wetlands along the U.S. coast for assessing environmental impa cts on U.S.
A digital base map in which geographic objects are depicted using a grid of pixels, with the color of each pixel individually defined. Examples of raster maps include aerial imagery or scanned paper maps.
Real Time ...
Among others the metadata should contain the accuracy of the features, the accuracy and resolution of the pixels, the date and completeness of the data (related to each included feature), the standard of the data set (if it is a standardized product, ...
Raster data represent features as a matrix of cells within rows and columns in continuous space. These cells are formed by pixels of a specific dimension size, and can be described as either "cell-based" or "image-based" data.
Cell-based Data ...
Digital Orthophotography - A photo-quality digital image of surface features in their geometrically corrected, true map projection. The orthorectification process ties each pixel in a digital image to its true earth location.
Spatial data: Date that define a location. These are in the form of graphic primitives that are usually either points, lines, polygons or pixels.
row
1. A record in an attribute table. The horizontal dimension of a table composed of a set of columns containing one data item each.
2. A horizontal group of cells in a grid, or pixels in an image.
Most basic element of information in a raster or grid description of spatial elements. Its shape is usually rectangular and it has an implicitly defined size and geographic position. (Also referred to as a pixel.)
Central Meridian ...
information, managed and stored as a unit, usually on some form of mass-storage system such as magnetic tape or disk. A GIS database includes data about the spatial location and shape of geographic features recorded as points, lines, areas, pixels, ...
 See also: Image, Information, Map, Resolution, Feature
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