Raster Data Archives - GIS Geography

Rasterization and Vectorization: How to Convert Data Formats

Rasterization converts vectors into rasters. While vectorization transforms rasters in vectors. We explain how to go from one data model to the other.

Lossy Compression vs Lossless Compression

Lossless Compression vs Lossy Compression

Lossless compression (like JPEG) retains values and lowers file size. However, lossy compression (like LZ77) reduces file size by eliminating redundancy.

How To Vectorize Image Files Automatically with ArcScan

You can take any image, and you can vectorize it with ArcScan. This means you’ll spend less time digitizing and more time doing other important things.

Raster Resampling for Discrete and Continuous Data

For raster resampling in GIS, you can use bilinear and cubic convolution for continuous data as well as nearest neighbor and majority for discrete data.

How to Fill NoData for Raster Data

SAGA GIS has a quick and dirty tool to fill NoData holes with raster data. We show you how to close gaps in DEMs or any raster data with holes in it.

What is Bit Depth for Satellite Data (and Images)

Bit depth is the amount of detail in each pixel expressed in units of bits. 1-bit rasters contain 2 values while 8-bit rasters range from 0-255

Image Compression and Encoding for Raster Data

Deploying efficient raster GIS compression techniques means reducing storage space. It can save money, time and also help network performance.

Vector vs Raster: What’s the Difference Between GIS Spatial Data Types?

The main spatial data types are vectors and rasters. Rasters have grid cells while vectors are points , lines and polygons consisting of vertices & paths.

GIS Analysis

Map Algebra: Global, Zonal, Focal and Local Operations

Map algebra is a cell-by-cell combination of stacked raster grids. It uses math-like functions with arithmetic, statistics and trigonometry operators.

Unsigned Integer vs Signed Integer for Raster Data

Unsigned integer rasters are non-negative numbers. Signed integers can store negative values. IMG, TIFF & GRID formats are acceptable for signed integer