![]() These coordinates, also known as vertices, define the shape of an object such as a river, building, forest, road, etc. While raster data is composed of cells in a matrix, vector data is composed of XY coordinates. One of the main differences between raster vs vector data is how it is represented. In an image, each pixel will have a red, green, and blue value, but the value of a pixel could also represent average rainfall, temperature, elevation, CO2 levels, etc.Įvery pixel in a raster dataset is identical in size and shape, and the amount of land each pixel represents is known as the spatial resolution. Each pixel in this grid, also referred to as a cell, contains a value of some sort, which represents a piece of data. Raster data is represented as a matrix of pixels arranged into rows and columns, aka, a grid. So, what is raster vs vector data, and which is best? Below, we’ll dive into everything you need to know about these two data representations. While attribute data is always represented in tabular format, geospatial data is a bit more varied, as it can be represented in either vector or raster forms. What makes GIS so interesting is that it can handle both attribute data, which describes the characteristics of a feature, and geospatial data, which describes the absolute and relative location of a feature. However, a lot of programs deal with data. Boca Raton, FL: CRC Press.Without data, there would be no reason for GIS to exist the whole point of GIS is to create, manage, analyze, and map data. A computational introduction to digital image processing (2nd ed.). In general, vector images require less memory to store necessary data compared to raster images. A vector image can be converted into a bitmap image of the required resolution, but it is rather difficult to convert the bitmap image into a vector without loss of quality. It is noteworthy that vector graphics can be easily transferred to raster format. Thus, vector images are based on geometrical formulas, while raster pictures have pattern dots. ![]() The Adobe Illustrator and CorelDraw programs are more appropriate for working with vector images. Although Adobe Photoshop allows working with vector images, it is still a raster editor. For example, various logos, business cards, and banners for websites need vector images in terms of design. Vector images are especially useful when there is a need to increase a photo or any other picture without losing its quality. In other words, a vector image includes information in the form of formulas and mathematical calculations, having a small size regardless of the actual scale of the depicted canvas (McAndrew, 2015). A vector image contains information about the positions of points as well as data about the line passing through the reference points. Vector images do not consist of dots containing color information, but reference points and vector lines connecting them. As a result, the image is distorted, and its small details become illegible. To reduce the raster pattern, one has to transform several neighboring points into one or throw away extra points. To enlarge an image, it is necessary to increase the size of the squares, and then it becomes stepped. According to McAndrew (2015), the mentioned images are also difficult to scale and even harder to edit. The computer remembers the colors of all the squares in a row in a certain order, which explains why bitmaps require more memory to store information. A raster image, unlike a vector image, is capable of transmitting a realistic image with a lot of small details. For example, any digital photo consists of these multicolored dots. Looking at the screen with thousands of dots of different colors and shades, people identify objects and images composed from them (McAndrew, 2015). The more points on the plane and the smaller they are, the more one sees the image. In bitmap images, each square called raster has its color and brightness, composing a mosaic.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |