![]() ![]() Global Mapper supports flexible raster data display, including contrast adjustment, support for multi-band data, pan sharpening, image tiling, and mosaicking with no need for additional modules.Īdding to the contrast adjustment options available for raster image data is Histogram Matching, which allows the color channel histograms of one layer to dictate the histogram adjustment in others. The new wireless direct data transfer capability allows the easy sharing of data, file exports, and feature templates from the desktop version of Global Mapper to Global Mapper Mobile, a mobile app, available on iOS and Android, for taking data into the field for reference and GPS-enabled data collection During export, data can be tiled into smaller or more manageable files, or the export area can be cropped to a defined area or to the extent of the current screen view. Vector, raster, and elevation data can be exported in virtually every common file format as well as many proprietary types. With new and modified formats being added on an ongoing basis, you can be sure that the software will never be out of date with your data. Offering direct access to over 300 raster, vector, and elevation data types, Global Mapper supports virtually all types of geospatial data right out of the box, no add-ons required. Raster vs vectorīoth types of data are very useful, but there are important differences.One of the unique and defining characteristics of Global Mapper is its extensive and varied data format support. The vector version can also store additional context information about these features – the attributes – a very important aspect. To reproduce the building in a GIS the computer reads these values and draws a line linking the coordinate positions. The position and shape of a building is captured as a series of four pairs of numerical coordinates. An area is defined in a similar way, only with the first and last points joined to make a complete enclosure.A line is defined by a sequence of coordinate pairs defining the points through which the line is drawn. ![]() A point is defined by a single pair of coordinate values. ![]() The features are recorded one by one, with shape being defined by the numerical values of the pairs of xy coordinates, so that: Vector data can be thought of as a list of values. To reproduce the image the computer reads each of these cell values one by one and applies them to the pixels on the screen. The major use of raster data involves storing map information as digital images, in which the cell values relate to the pixel colours of the image. ![]() A value is stored in each of these cells to represent the nature of whatever is present at the corresponding location on the ground. The entire area of the map is subdivided into a grid of tiny cells, or pixels. Raster data can be thought of as being similar to a digital photograph. These numerical values can be used to translate map information into digital form, in both vector and raster formats. All locations and shapes can be defined in terms of x and y coordinates from a given grid system. These numbers refer to coordinates from the British National Grid. Look at Ordnance Survey (OS) paper maps and you will notice, along the sides, there are a series of numbers associated with a grid covering the whole map area. These coordinate systems can be local, national or international. Coincidentally maps reference geographical locations on the earth's surface through a system of coordinates. Computers store information in sequences of binary digits (bits), which form a code for every possible number or letter. ![]()
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