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How to extract Digital Elevation Model and Orthophoto mosaic from Scanned Analog Aerial Photographs in Agisoft Metashape. 

In this tutorial, I will show you a new application from ArcGIS Enterprise/Portal for ArcGIS Family. The application is called Ortho Maker. This app is designed to provide Photogrammetric UAV Photo processing inside ArcGIS  Enterprise/Portal. If you are familiar with DroneDeploy or Pix4D Clouds, this application offers similar features.  Because it is implemented inside ArcGIS Enterprise Environment, you can publish the processing results as ArcGIS API Services, either in tiled static map services or dynamic image services. Previously, ESRI has released Drone2Map as a desktop-based UAV Processing software a few years ago, and UAV photogrammetric processing capabilities also have been implemented in ArcGIS Desktop and ArcGIS Pro. So Ortho Maker is the ESRI answer for Cloud-based UAV Photogrammetric processing needs.  Ortho Maker implementation needs an instance of ArcGIS Image Server (functioned as raster analysis module and raster hosting server). But for optimal performa...

Satellite Imagery Orthorectification usually uses interior/exterior orientation information for the photogrammetric collinear equation to works. Satellite Imagery vendors usually gave this information to the users in a form of a sequence of constant numbers written in a certain format and can be consumed by photogrammetry software. This information is called Rational Polynomial Coefficients (RPC) and is usually provided along with other imagery metadata by satellite imagery companies.  This RPC information became the backbone of orthorectification. Without this RPC information, orthorectification can't be done and can't be performed. Fortunately, some remote sensing software can compute this RPC information from the Sensor Characteristics information and it can also be more accurate if complemented by Ground Control Points measured in the field or measured from more accurate imagery.  I will explain how to do this later. In this article, I will show you how to perform orthorec...

Satellite Imagery Orthorectification usually uses interior/exterior orientation information for the photogrammetric collinear equation to works. Satellite Imagery vendors usually gave this information to the users in a form of a sequence of constant numbers written in a certain format and can be consumed by photogrammetry software. This information is called Rational Polynomial Coefficients (RPC) and usually provided along with other imagery metadata by satellite imagery companies.  This RPC information became the backbone of orthorectification. Without this RPC information, orthorectification can't be done and can't be performed. Fortunately, some of the remote sensing software has capabilities to compute this RPC information from the Sensor Characteristics information and complemented by Ground Control Points measured in the field or more accurate imagery.  I will explain how to do this later. In this article, I will show you how to perform orthorectification using custom or...

When building RPCs for digital camera aerial photography and pushbroom sensor imagery, you will need to enter various required parameters such as   principal points ,   focal lengths and pixel sizes , and   incidence angles . This section provides guidelines on determining these values. Principal Point Coordinates Principal point coordinates are often set to [0.0, 0.0], which assumes that the principal point is the center of the image for a frame central projection and the center of each scan line for a line central projection. A laboratory calibration report should provide the principal point coordinates. Focal Length and Pixel Size Focal length is the orthogonal distance from the perspective center to the image focal plane. Pixel sizes correspond to the CCD cells (detectors of the camera that captured the images). Typically, aerial digital cameras and satellite pushbroom sensors have square pixels, which means that the pixel size is the same in the x and y dimensions. F...

Agisoft Metashape (formerly Agisoft Photoscan) is a well known Photogrammetric UAV/Drone Processing software. Using this software you can make DEM, DSM, DTM, orthophotos, orthomosaics, and 3D model from Drone / UAV survey. In the latest version, this software expanded its capabilities not only enable to process UAV/Drone Photos, but also Stereo / Tri Stereo Satellite Imagery. This feature is awesome because existing Stereo Satellite imagery processing is only can be facilitated by expensive remote sensing software like ERDAS IMAGINE, ENVI, PCI Geomatica, Socet Set. Different with dedicated remote sensing software, Agisoft Metashape can generate DEM without GCPs. Photogrammetry become more simple, altough if we talks about accuracy, that is another problem. Anyway here is my experiment and experience when I am trying the Agisoft Metashape for stereo satellite imagery processing. 

ENVISAT is the flagship earth observation satellite of the European Union from 2000 to 2010. It brings a huge number of payloads and sensors. The most well-known are AATSR, ASAR, and MERIS. ASAR (Advanced Synthetic Aperture Radar) is the continuation of the ERS1-ERS2 satellites which operate in the nineties to early 2000. The satellite now has been decommissioned due to communication problems, but the data is still considered precious because it is recording the earth phenomena in the last decade.  ENVISAT ASAR data has been available for the public, however, its access right now is quite limited due to EU rules. ENVISAT ASAR data comes in with a wide range of data formats, and all of them are supported to read and process in ESA SNAP Software. So if you have access to ENVISAT ASAR, I advise using ESA SNAP if you want to get maximum benefits of the data. Nonetheless, other SAR Software can also process this data. Recently I have access to the data and I start to play around with th...

How to perform orthorectification in ArcGIS using DEM and imagery metadata