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Showing posts from December, 2017

stream / river Network extraction from a DEM using ArcGIS Desktop

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Hello, this is the second part of my gis hydrology video tutorial at youtube. This time I am going to show you how to extract stream or river network from a DEM in ArcGIS, check it out  

watershed / river basin / catchment extraction in ArcGIS

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Hello, this is my newest published tutorial at youtube. In this tutorial I will show you how to delineate watershed, catchment or river basin from a DEM using ArcGIS Software. thanks for watching and subscribe me at youtube to get notified about future tutorial.

Perbedaan SRTM C-Band DEM dan SRTM X-Band DEM

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Saya tidak tahu apakah sudah banyak orang yang mengetahui apa tidak, tapi saya baru tahu belakangan ini bahwa DEM dari data SRTM itu ada dua versi. Bukan dua versi resolusi spasial (30 meter dan 90 meter) yang saya maksud, tetapi dari dua sensor SAR yang berbeda. Sebagaimana yang kita ketahui, SRTM adalah misi pemetaan topografi global menggunakan two pass interferometry along track menggunakan wahana pesawat ulang alik yang dipasangi sensor Radar SAR. Misi ini dilaksanakan tahun 2000 dan menghasilkan data DEM dengan resolusi 90 meter dan 30 meter untuk seluruh dunia (kecuali daerah dekat lintang tinggi). Misi SRTM dilaksanakan setelah misi pendahuluan sukses dilaksanakan tahun 1994 (misi SIR-C/X-SAR). Hanya misi tahun 1994 tidak dilaksanakan dalam konfigurasi interferometri, sehingga tidak dapat menghasilkan data DEM. Nah misi SRTM tahun 2000 menggunakan sensor dan wahana yang sama dengan misi tahun 1994, sehingga dalam misi ini terdapat dua sensor SAR, satu sensor beroperasi di

KML / KMZ to SHP / Shapefile Conversion in QGIS

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KML (Keyhole Markup Language) or its compressed form KMZ is the file format used in Google Earth or Google Maps products. This format has a similar structure to XML, so it could be opened in Text Editor without any problems. This format is flexible because it is could store vector data as well as raster data. Because it is designed as a geospatial data format in vector or raster, technically it is interoperable with common geospatial data formats like shapefile, geodatabase, MapInfo, or GeoJSON.  And because it is an interoperable geospatial data format, it can be converted into a more common GIS format like shapefile. Many GIS and Remote Sensing software have capabilities to read KML or KMZ and converted them into Shapefile for example. However, you must be careful when you try to convert KML data into Shapefile. It is because KML format stores the attribute data into HTML table, so if your software didn't have capabilities to convert HTML table into native DBF table used in Shape

removing clouds from aerial photographs/satellite imagery in ArcGIS

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