UPDATE 27/12/2016: update for TypeScript 2.0

Recently I am working on a web mapping project based on Angular 2. There isn’t much data on how to create web map using Leaflet in TypeScript. So I think it’s good to write a post on it.

Do you still feel inconvenient when converting GeoJson to other data formats in Node.js?

I have been doing GIS work for quite a while and I do hate to download data from multiple sites every time. So I decide to collect those commonly geospatial data and make my own database. Of course, like all open-source people do, I’d love to share my work with you. The first release is the U.S. nationwide U.S. boundary. This dataset include nation, state, county, place, census block, and census tract. The source data come from U.S. Census Bureau and you can find the metadata here.

Multiple formats provided: shapefile, geojson, and a postgis database dump.

Two months ago I have written a small python package pymasker to generate mask from the Quality Assessment band of Landsat 8 image and MODIS land products. This package is gaining popularity, But scripting may not be convenient for users who are not familiar with programming, therefore I create a ArcMap python toolbox based on this package for interactive masking.

The length of remote sensing pixel value is constrained by a predefined pixel value type. It is an unchangeable property for each remote sensing image and saving an unsupported value to a image may cause unpredictable errors like application crash or information loss resulted from implicit data type conversion.

I am glad to announce that the project ArcMap Raster Edit Suite (ARES) has proceed to its second major version 0.2.0! A completely new toolbar Raster Painter is added into the add-in. Many people have realized that editing pixels using tools in Raster Editor may be labor intensive, especially when editing large number of pixels. This toolbar is here to provide an ultimately flexible solution to edit pixels, by painting new values on it. The editing style is design to be similar to draw image and picture. You can find similar toolbars in ArcMap like ArcScan and Raster Painting, but they are not designed for raster data modification. Of course, a very close analogy is Paint on Window.

Update Since 0.3.0, most class and function names have been updated according to pep8.

Days ago when I published the first version of pymasker for masking Landsat 8 image, Dr. Robert A. Washington-Allen suggested me whether the package would be used for MODIS products. After I read technical documents of MODIS, I realize that the Quality Control bits of MOIDS products has the same structure as the QA band of Landsat 8. Therefore, I update the package to adapt MODIS products (or other NASA products with similar QC/QA bits).

Editing single pixels of a raster layer is a common task in daily GIS and RS practice. For example

• Removing misclassified pixels from a land cover classification result

• Creating a set of multiple raster layers with minor difference for model simulation

• etc.

In ArcMap we use Raster Calculator and Reclassification tool as many instructions suggest. However, these tools are designed to edit the layer as a whole and they are not flexible enough for minor modification. If ArcMap allows us to edit single features of a vector layer, why we cannot edit single pixels of a raster layer in ArcMap? That is the reason why the project ArcMap Raster Edit Suite (ARES) starts. It aims at providing an ArcMAp Add-In with tools to allows single raster pixels editing, just like what we can do with the vector layer. Flexible, quick and neat!

The problem of sampling rule in Support Vector Machine raised in the discussion when I was in the course Advanced Remote Sensing.

The quality of training sample has deterministic influence to the accuracy of supervised classification methods. A properly designed sampling rule plays a substantial role in yielding an informative training sample set. The design of sampling strategy depends on both the characteristics of objects of interest and the applied classification methods.

Pymasker is a python package to generate various masks from the landsat 8 Quality Assessment band and MODIS products.