Why is raster vaster

Why ask that question in ? Is it still an issue? Years ago, GIS geeks argued about which format was better, faster, or easier. Are GIS geeks still fighting the raster vs. Do we really need both types of data in Digital Coast? I would say emphatically YES! You might start by drawing a sketch on your napkin.

On your napkin you are describing relationships to get your point across. You probably generalized features such as putting a single point for a building, or drawing a line for the road or river. Maybe you drew a box for a church. Without thinking about it, you selected a projection, scale, and a vector feature type line, point, polygon in your napkin map.

And even though you are the best napkin map cartographer on the planet, you introduced errors! All maps including napkins are representations of reality and inherently wrong! Can you imagine trying to draw that napkin map using a raster characterization?

You will spend the time to draw thousands of tiny blocks covering the napkin and you would need multiple pens to color and characterize the data. For example, if you start with a digital camera hand, aerial, or satellite you already have raster data. Depending on the device, they may be called pixels or dots. If you hear dots per inch DPI or megapixel 1 million pixels , you are talking raster!

If you zoom or magnify in really close you can even see the individual dots or pixels. Your map, photo, or scanned document is just a collection of pixels arranged in rows and each small pixel has a value. Have you ever heard that phrase when debating whether to use raster or vector data for visualizing layers e.

Aside from the imperfect English, is vector indeed corrector? In this post we take a look at the key differences between these two types of spatial data and discuss when it is appropriate to use one or the other. Raster data is made up as a matrix of pixels, also referred to as cells in much the same way as you might find when working within a spreadsheet.

Think of walking over a field divided into a grid of squares with each square representing a value which can be discrete e. Raster data can be added as a basemap within the CARTO platform which by default uses vector graphics for map rendering. Rather than working with a matrix of cells, vector data stores basic geometries made up of one or more interconnected vertices , with three key types:.

Vector data is fully supported across the CARTO platform since Location Intelligence relies on the ability to analyze and visualize data in such a format.

Some specific use cases can only be achieved with raster data e. When working with raster or vector data within the sphere of spatial analysis there are of course a myriad of use cases that can be employed but as has been touched upon already there are specific cases where it can make sense to use one over another.

For example due to the nature of its collection, raster is often the only choice when working with remote sensing data captured by cameras on planes or satellites.

The spatial resolution of such data will be determined by the capabilities of the sensor used to take an image which is why it can be subject to a pixelated look when using a low resolution. They can be scaled infinitely. Vector images are comprised of shapes, and each shape has its own color; thus, vectors cannot achieve the color gradients, shadows, and shading that raster images can it is possible to mimic them, but it requires rasterizing part of the image — which means it would not be a true vector.

Here are the three most important differences between raster and vector. Since raster images are comprised of colored pixels arranged to form an image, they cannot be scaled without sacrificing quality. If you enlarge a raster, it will pixelate, or become blurry.

The lower its resolution pixels-per-inch , the smaller the image must be to maintain quality. The difference is easy to see when you zoom on in a raster versus a vector; you can see individual pixels in the raster file, but the vector is still smooth. With vectors, resolution is not a concern. Raster images are capable of displaying a myriad of colors in a single image and allow for color editing beyond that of a vector image. They can display finer nuances in light and shading at the right resolution.

Vector images are scalable, so that the same image can be designed once and resized infinitely for any size application - from business card to billboard. Even if it were possible, the process would be excruciatingly tedious, as every color change would require a new shape to be created. Rasterized images, on the other hand, are perfectly capable of rendering true-to-life graphics: visually-perfect color blends, shades, gradients, and shadows.

Because rasterized images must contain all the information necessary to render the image pixels, colors, arrangement of pixels, etc. Compression can help minimize those file sizes, but compared to vectors, rasters take up a lot of space.

Since vectors rely on calculations to be performed by the programs that load them, the only information they need to contain are their mathematical formulas. This table compares some of the differences, advantage pros , and disadvantages cons between raster and vector images. Raster images are best for photos, while vectors are best for logos, illustrations, engravings, etchings, product artwork, signage, and embroidery.