Advantages of raster and vector data models in software

Jun 06, 2017 difference between vector and raster data model vector data model. Raster data models incorporate the use of a gridcell data structure where the geographic area is divided into cells identified by row and column. Elevation, as a continuous land field characteristic, is usually stored in a vector file for easier data management, but is more suitable to be represented by a. In general terms what applications, processes, or analysis are each suited for. This is because vector images do not support the kind of color blends possible in raster images. So if you consider creating a data structure for rastor it would be a 2d array, each x,y coordinate refer a square in the are and it can have a certain predefined characteristic e. A classification of software components commonly used in geographic information systems.

Vector and raster data in gis computer science essay. The advantages and disadvantages of vector and raster data. Raster data models present information through a grid of cells. Quadtrees recursively divide an area into quadrants until all the quadrants at all levels are homogeneous. Does anyone have some small, concise, effective pictures which convey and contrast these two fundamental data representations. The software provides several tools to perform spatial queries using grids. A comparison of vector and raster gis methods for calculating. The human eye is very good at interpreting images and so using an image behind vector layers, results in maps with a lot more meaning. Each of these units is composed simply as a series of one or more coordinate points, for example, a line is a collection of related points. In order to visualize natural phenomena, one must first determine how to best represent geographic space. The human eye is very good at interpreting images and so using an image behind vector layers, results in maps with a.

Types of raster data model advantages, disadvantages just. There are some important advantages and disadvantages to using a raster or. There are several advantages and disadvantages for using either the vector or raster data model to store spatial data. A file of spatial data that is a just a collection of coordinate strings each entity or piece of spaghetti is represented by one data entry there is no topology advantages. Difference between vector and raster data model vector data model. A raster model tells what occurs everywhere, while a vector model tells where everything occurs. Continuous phenomena are more easily represented with the raster data model.

Can overlay displays easily can easily manipulate data table can have many variables linked to one geographic file better suited for map output a simple data structure. A simple data structurea matrix of cells with values, representing a coordinate, and sometimes linked to an attribute table. Vector is a data structure, used to store spatial data. Vector data models can represent all types of features with accuracy. Data models in geographical information systemgis 1.

In some gis packages, the dbms is based in an existing software, i. Vector data models early vector model unstructured does not record or enforce connections between line segments or shared polygon boundaries. Here, i just want to give you a quick comparison between the two, and show you how you can actually use both of those inside the software. In comparison with the raster data model, vector data models tend to be better representations of reality due to the accuracy and precision of points, lines, and polygons over the regularly spaced grid cells of the raster model.

Basically, vector images are described by geometric primitives which describe lines, points, polygons, and curves which can be attributed with shades and colors. It unifies the storage of multiple raster data types, including satellite imagery, gridded data e. There are some important advantages and disadvantages to using a raster or vector data model to represent reality. These features are the basic features in a vectorbased gis, such as arcgis 9.

Shapefiles are a common filebased data format used in gis software. They are very different from raster images which are grids of pixels. Jun 06, 2017 data models in geographical information systemgis 1. Since most input data is in vector form, data must undergo vector to raster conversion. This value can be interpreted to mean several different things. This results in vector data tending to be more aesthetically pleasing. Simple data structures overlay and combination of maps and remote sensed images easy some spatial analysis methods simple to perform simulation easy, because cells have the same size technology is cheap disadvantages of raster data structures. Vector representation vector representation of data in the vector based model figure 4, geospatial data is represented in the form of coordinates. Below is an example of a classified raster dataset showing land use.

Usually every things have some advantages and disadvantages. Creating a photorealistic vector image, for example, is possible, but not advised. For raster data, this is the size of the individual cell or pixel. Raster data model record value of all the points of the area covered which required more data storage than model represented by the vector model. Besides increased processing requirements this may introduce controversy over data due to generalization and choice of inappropriate cell size. In particular, the quadtree data structure has found some. In this model, space is not quantized into discrete grid cells like the raster model. Allows for efficient encoding of topology, and as a result more.

Wiseimage allows you to make fast changes do editing and correction or automatic and semiautomatic rastertovector conversion of technical drawings, scanned maps, plans, drafts, sketches and. Raster grids are usually made up of square or rectangular cells. In comparison between the two forms of data, there are particular advantages and disadvantages of use. What are raster and vector data in the gis context. While mapping the real world, we have a choice between, representing it with the vector data model, or the raster data model. You will know the difference between raster and vector data in gis you will know when each data model is the best choice for a particular analysis or map. Raster data is less expensive to create computationally compare to vector graphics. Vector models are useful for storing data that has discrete boundaries, such as country borders, land parcels, and streets. Data models are a set of rules andor constructs used to describe and represent aspects of the real world in a computer. Jan 14, 2011 integrated raster and vector processing capabilities are most desirable and provide the greatest flexibility for data manipulation and analysis. Best raster to vector conversion software wiseimage. Since most input data is in vector form, data must undergo vectortoraster conversion. While the term raster implies a regularly spaced grid other tessellated data structures do exist in grid based gis systems.

Many people use raster data as a backdrop to be used behind vector layers in order to provide more meaning to the vector information. Besides increased processing requirements this may introduce data integrity concerns due to generalization and choice of inappropriate cell size. Unlike vector data models, which show geographic data through points, lines, or polygons, raster data is displays one value in each cell. Both raster and vector methods present data in their own format, with their own advantages and. Vector vs raster data models there are two spatial models for storing geographic data the vector data model and the raster data model. What kind of applications would each be most suited to. With the vector and raster data model, a very basic guideline just to get started with is that, discrete objects are easily represented with the vector data model. When should we use raster and when should we use vector. Advantages and disadvantages of raster and vector data models. The advantages and the disadvantages of vector images.

Today we shared some advantages and disadvantages of raster and vector data. Data is represented at original resolution and form without generalization. The main spatial data types are vectors and rasters. Data can be represented at its original resolution and form without generalization. Vector models are useful for storing data that has discrete boundaries. Apr 15, 2016 since most input data is in vector form, data must undergo vectortoraster conversion. In rastor, the area under consideration is divided into equal squares and a characteristic assigned to it. Some personal computer pc packages utilize vector structures for data input, editing, and display but convert to raster structures for any analysis. Advantage and disadvantage of using raster and vector data. It is often difficult to compare or rate gis software that use different data models. Advantages of vector data models over raster model answers.

Learn vocabulary, terms, and more with flashcards, games, and other study tools. Introduction to gis and spatial data vector and raster comparison vector raster compact data structure for homogenous areas. Apr 29, 2011 list advantages and disadvantages of vector and raster data for gis. Before exploring the advantages and disadvantages of vector and raster data first got some idea about these two terms. Vector data models use points and their associated x, y coordinate pairs to. In this context, the conversion of vector features such as. Thematic maps can also result from geoprocessing operations that combine data from various sources, such as vector, raster, and terrain data. Nongis graphical software, including cad and drawing programs such as adobe illustrator, are also based on the vector model. In contrast to the raster data model is the vector data model. These features are the basic features in a vector based gis, such as arcgis 9. Advantages of vector data models over raster model. Vector data is comprised of lines or arcs, defined by beginning and end points, which meet at. The gis spatial data model university of washington.

For example, you can process data through a geoprocessing model to create a raster dataset that maps suitability for a specific activity. Raster data has issue while overlaying multiple images. The main difference between vector and raster graphics is that raster graphics are composed of pixels, while vector graphics are composed of paths. Wiseimage for windows is the new generation of 2d standalone, raster to vector conversion software with raster editing and drawing revision features. The nature of vector images makes them most suitable for images with few colors. Index introduction components of gis data types in gis data representation raster data model vector data model differences between raster and vector triangulated irregular network tin. Find out more on the spatial data models commonly used. The two primary types of spatial data are vector and raster data in gis. In vector data, the basic units of spatial information are points, lines arcs and polygons. Historically, it has generally been accepted that raster calculations were faster, while vector methods gave higher accuracy kennedy and meyers, 1977. Vector images are mathematically defined based on geometric characteristics. Vector data models use points and their associated x, y coordinate pairs to represent the vertices of spatial features, much as if they were being drawn on a map by hand aronoff 1989. What is the difference between vector and raster data models. While deciding whether to use a vector data model or raster data model in your work it entirely depends on the data you have as input and what your goals are for displaying or analyzing the data.

A raster graphic, such as a gif or jpeg, is an array of pixels of various colors, which together form an image. Raster data models present information through a grid of cells raster grids are usually made up of square or rectangular cells. Data structures and data models raster and vector refer to a particular data model a data structure refers to a particular implementation of either the raster or vector model 4 topology the spatial relationships between things an important distinction between data models and data structures. Aug 22, 2016 whilst there are many advantages to vector images, they are unsuitable for some uses. Each of these units is composed simply as a series of one or more coordinate points, for example, a line is a collection of related points, and a polygon is a collection of related lines. Mrr is a completely new raster data format that reimagines how raster data is stored and what data can be stored as a raster. Most gis software applications mainly focus on the usage and manipulation of vector geodatabases with added components to work with rasterbased geodatabases. One of the strengths of the vector data model is that it can be used to render geographic features with great precision. List advantages and disadvantages of vector and raster data for gis. Elevation, as a continuous land field characteristic, is usually stored in a vector file for easier data management, but is more suitable to be represented by a raster data model.

Graphic output is usually more aesthetically pleasing traditional cartographic representation. Vector data can can better represent topographic features than the raster data model. One of the strengths of the vector data model is that it can be used to. In vector data, the basic units of spatial information are points, lines and polygons. Vector data is comprised of lines or arcs, defined by beginning and end points, which meet at nodes. Index introduction components of gis data types in gis data representation raster data model vector data model differences between raster and vector triangulated irregular network tin digital elevation model dem conclusion reference. There are many software development life cycle models, one of them is. Raster data is more suited to mathematical modelling and analyses. What are raster and vector data in gis and when to use. There are many analysis that make use of both data models i. What is the difference between vector and raster data. Advantages and disadvantages of vector and raster data. Lecture 1 intro to gis and gis vector and raster data models. Jan 14, 2011 since most input data is in vector form, data must undergo vector to raster conversion.

Data models are a set of rules and or constructs used to describe and represent aspects of the real world in a computer. Gis and modeling overview the term modeling is used in several different contexts in the world of gis, so it would be wise to start with an effort to clarify its meaning, at least in the context of this book. Vector representation of data in the vector based model, geospatial data is represented in the form of coordinates. But what is the difference between raster and vector data. The basic spatial data model is known as arcnode topology. In the previous article, we have discussed about different types of vector data model and data structures. The majority of output maps from gridcell systems do not conform to highquality cartographic needs. The use of a raster data model confers many advantages. Vector and raster are the two common data types used in gis. The raster data model, along with the vector data model, is one of the earliest and most wide ly used data models within geographic information systems tomlin, 1990.