Lecture

Spatial Data Interactions: Raster-Vector (summary)

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Description

This lecture discusses the combination of information from different layers for georeferenced phenomena analysis. It explores spatial interactions between raster and vector layers using QGIS tools like 'point sampling tool' for data transfer and 'zonal statistics' for calculating statistics within defined polygon areas.

In MOOC

Geographical Information Systems 2

The second part of the course deals with spatial analysis methods and georeferenced information representation techniques. In particular, you will learn how to:

Analyze the spatial properties of discrete variables, for example by quantifying spatial autocorrelation;
Work with continuous variables (sampling, interpolation and construction of isolines)
Use digital elevation models (DEMs) and their derivatives (slope, orientation, etc.);
Use geodata superposition techniques;
Produce cartographic docu

Official source

Related concepts (17)

Raster graphics

In computer graphics and digital photography, a raster graphics represents a two-dimensional picture as a rectangular matrix or grid of square pixels, viewable via a computer display, paper, or other display medium. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel. Raster images are stored in s with varying dissemination, production, generation, and . The printing and prepress industries know raster graphics as contones (from continuous tones).

Georeferencing

Georeferencing or georegistration is a type of coordinate transformation that binds a digital raster image or vector database that represents a geographic space (usually a scanned map or aerial photograph) to a spatial reference system, thus locating the digital data in the real world. It is thus the geographic form of . The term can refer to the mathematical formulas used to perform the transformation, the metadata stored or within the image file to specify the transformation, or the process of manually or automatically aligning the image to the real world to create such metadata.

Spatial database

A spatial database is a general-purpose database (usually a relational database) that has been enhanced to include spatial data that represents objects defined in a geometric space, along with tools for querying and analyzing such data. Most spatial databases allow the representation of simple geometric objects such as points, lines and polygons. Some spatial databases handle more complex structures such as 3D objects, topological coverages, linear networks, and triangulated irregular networks (TINs).

Raster graphics editor

A raster graphics editor is a computer program that allows users to create and images interactively on the computer screen and save them in one of many raster graphics (also known as bitmap images) such as JPEG, PNG, and GIF. Vector graphics editors are often contrasted with raster graphics editors, yet their capabilities complement each other. The technical difference between vector and raster editors stem from the difference between vector and raster images. Vector graphics are created mathematically, using geometric formulas.

Spatial analysis

Spatial analysis is any of the formal techniques which studies entities using their topological, geometric, or geographic properties. Spatial analysis includes a variety of techniques using different analytic approaches, especially spatial statistics. It may be applied in fields as diverse as astronomy, with its studies of the placement of galaxies in the cosmos, or to chip fabrication engineering, with its use of "place and route" algorithms to build complex wiring structures.

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