Collecting and interpreting information about the environment and the surface of the earth from a distance, primarily by sensing radiation that is naturally emitted or reflected by the earth's surface or from the atmosphere, or by sensing signals transmitted from a device and reflected back to it.

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0answers
26 views

Connect a photo and a DEM using landscape features

I'm helping with an image retake study in Alaska, we have historical (up to 100 years old) photos of the landscape (with lat/long) and we'll be retaking photos this year at the same locations. The ...
0
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0answers
34 views

How to calculate vertical exaggeration in stereoscopy?

How can I calculate the 'seen' vertical exaggeration of my set of orthophotos, when working with a stereoscope? What factors determine it?
2
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2answers
80 views

How to calculate LAI (Leaf Area Index) using Remote Sensing? [closed]

I am new in remote sensing, and I would like to ask the community what are some good methods to calculate the Leaf Area Index (LAI) using Remote Sensing Data, for agriculture mostly applications.
0
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0answers
17 views

How to extract coherence and covariance matrices of TerraSAR-X data?

I have obtained quad-polarized level 1b TerraSAR-X data from DLR. When I tried to read the data using PolSARpro, I understood that it is only capable of reading SSC format But my data is in MGD ...
0
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0answers
18 views

How can I find pixel spacing in azimuth and range and look angle from envi sarscape?

I have a quad-pol ALOS-PALSAR dataset, which I have read using Envi SarScape. Now I find to read the header or where the following information is written: pixel spacing azimuth pixel spacing slant ...
1
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0answers
20 views

How to make LISS-III image coloured

In order to study land use and land cover change from LISS-III images I want to see the image coloured (i.e. false-colour composite RGB) using ENVI 5.0. What is the procedure?
4
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1answer
66 views

Pan sharpening of SPOT and Landsat images

Is there a way I can pansharpen SPOT and Landsat images? I have Panchromatic bands from QuickBird and WordlView-2 images and would want to pansharpen Landsat and SPOT, while still retaining features ...
2
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1answer
111 views

Creating composite band mosaic of sentinel 2 data with arcpy

I previously useda simple script that went through many Landsat satellite images, and for each folder it found it made a composite band raster. The script was as follows: import arcpy import os ...
1
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0answers
20 views

Pre-processing in remote sensing [duplicate]

I have a bit of confusion on the pre-processing of remote sensed images. Do atmospheric correction methods such as Dark Object Subtraction convert the DN into reflectance values? If not, it is ...
0
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0answers
51 views

Maximum Likelihood Classification in ENVI

I am a new ENVI user and I am trying to perform a supervised classification of a Landsat 8 image with the maximum likelihood algorithm. In order to run the classification, I have to insert a Scale ...
1
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1answer
37 views

How to define a threshold in Principal Component Image for Urban mapping?

I am working on an Urban mapping and i would like to know how i could define a threshold value for extracting built-up areas from a PC (Principal Component) Image ? I am interesting on how to ...
1
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0answers
53 views

salt marsh recession mapping with landsat/WV, IKONOS) [closed]

I am trying to detect timing and pattern of change in a particular salt marsh (low marsh sitting close to a high marsh). Basically, I'm interested in detecting changes in the leading edge for ...
0
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1answer
36 views

Provider of hyperspectral imagery SWIR band

I'm looking for aerial hyperspectral imaging with SWIR band; size of ground pixel should not exceed 5m and dated not earlier as 2015. Could you propose provider such of data ? Area of interest is ...
2
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1answer
70 views

Sentinel 2 Tool Box on Commandline

Has anyone tried to use the Sentinel toolbox in command-line? I have downloaded the SNAP tool and installed on a Ubuntu workstation and the GUI works well. I now want to want to use it in a ...
-1
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1answer
64 views

Estimation of Land Surface Temperature using ENVI 5.2

I am doing research about land surface temperature using Landsat 8 image. However, I have a problem with them. I have read literature but i can not do it in ENVI 5.2. Could you help me ...
2
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1answer
35 views

Getting exact maximum daily temperature using remote sensing?

I have a problem I want to find the land surface temperature of Bangkok using landsat8. I have everything to get it but the problem is landsat images are obtained during morning time but the maximum ...
0
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0answers
24 views

About land surface temperature?

I have a problem I want to find the land surface temperature of Bangkok using landsat8. I have everything to get it but the problem is landsat images are obtained during morning time but the maximum ...
0
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0answers
10 views

Mosaic georef is a few pixels off for half of my image, how to georeference?

I have two sat. images from the same platform on two different dates. The images overlap each other nicely, but I cant get them to accurately mosaic into one raster image. I merged the two photos ...
3
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2answers
455 views

Opening image files with Sentinel 2 toolbox

Anyone worked with the Sentinel-2 toolbox/SNAP? It doesn't support sentine-2 data to be opened directly. I tried opening .safe, .zip and .xml files.
1
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1answer
36 views

Adding Subdatasets in ArcMap

I have some MODIS imagery that I want to display in true colour, however when I add the data it gives me 13 subdatsets to choose from. I've never worked with this before and I'm not sure which ...
1
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0answers
26 views

Difference between radiometric correction at surface and at sensor in ENVI

I want to ask you about the difference between the radiometric correction at surface and at sensor in ENVI software, I do the two in flash and radiometric correction and the results was same image. ...
3
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0answers
64 views

Using original Landsat multispectral image or pan-sharpened image in land cover classification?

I am currently creating land cover maps of a number of national parks across Asia from Landsat 8 imagery and also later from SPOT imagery. I plan to use supervised classifications in ERDAS IMAGINE and ...
5
votes
3answers
156 views

Differentiating bare soil and urban areas in Landsat 4-5 land cover classification?

I am trying to classify a Landsat 4-5 image using the semi automatic classification plugin (QGIS). I always get misclassifications between bare soil and urban areas as they have similar spectral ...
0
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1answer
92 views

Land Surface Temperature

Estimation of Land Surface Temperature Contact measurements of emissivity values of the surfaces using thermal radiometers and spectral assessment of samples supplementedLST estimation ...
0
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1answer
72 views

Where can I find SRTM DSMs (digital surface model)?

I'm interested in finding a 30 meter DSM (digital surface model that includes canopy) from SRTM with the hope of creating a 30 meter canopy height model. I know that it can be done because the ...
-1
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1answer
37 views

About PolSDP software for SAR processing [closed]

Can anybody help me to find PolSDP software or provide a link from where I can download.
4
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2answers
69 views

Accessing the Quality Band for MCD12Q1 with MODISTools GetBands

I am using MODISTools (https://github.com/seantuck12/MODISTools) to process MCD12Q1 data, which, according to the LP DAAC website ...
3
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2answers
60 views

Difference between Ground Sampling Distance and pixel size in RapidEye

I am a bit confused about reading technical specifications on RapidEye satellites. I assumed that Ground sampling distance (GSD) and pixel size express the same meaning, while GSD is 6.5 m, and pixel ...
0
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2answers
54 views

Which one is best for atmospheric correction?

My aim is to determine surface temperature extraction by computing NDVI from Landsat 7 and Landsat 8. suggest me which method DOS (dark object subtraction) or FLAASH atmospheric correction in ENVI ...
1
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1answer
62 views

How to determine the bands from an aerial image?

I received a set of aerial images taken with a Canon camera, I don´t know which kind of lens it has, or if it has been modified. After performing split image algorithm in Qgis, I get four new files: ...
9
votes
2answers
153 views

How precise are overpass times of sun-synchronous satellites?

sun-synchronous satellites, as their name say, acquire scenes at the same solar time of the day when they pass over the same location. According to this site, sun-synchronicity is achieved by taking ...
7
votes
2answers
178 views

Are PDAL or PCL capable of producing LiDAR grid metrics?

I typically use Windows-based FUSION to generate grid metrics, which can be used to describe forest structural characteristics. From the FUSION documentation: GridMetrics computes a series of ...
2
votes
1answer
116 views

Existence of fiducials marks in a digital camera file

Existence of fiducials marks in a digital camera file I have created a generic digital camera file using Erdas 2015 with the following data in it: LPS Camera File Version: 2.0 Camera Name: "generic ...
4
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0answers
99 views

Counting number of plants in area using images from UAV?

How do I count the number of pineapple plants in a 1-hectare block? I have heard of these algorithms but I don't know how to do it. I'm still a newbie of QGIS, ArcGIS and ENVI. I have the NIR, RGB, ...
3
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2answers
251 views

Classify forest with NDVI from Landsat 8 and 7

I'd like to calculate the NDVI for multi-date satellite images of Landsat (7,8) to perform a change detection on the deforestation of the Amazon rainforest. I already acquired surface reflectance ...
1
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0answers
59 views

How to mosaic multiple MODIS images of Multiple months using MRT tool?

I have monthly MODIS images for 2001-2014. For few images mosaicing with reprojection can be done using MRT tool. However, for large number of images it's a cumbersome process. There are multiple ...
1
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1answer
110 views

Tutorial Vegetation Condition Index

Anybody here can help me regarding calculating Vegetation Condition Index (Kogan,2004) for Landsat?. Specially facing problem in NDVI_max and NDVI_min; which should be maximum and minimum value?
3
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0answers
39 views

Differences between mWm-2sr-1(cm-1)-1 and W/m^2 * sr * um

I'm confused about the use of this quantity. For example eumetsat on pag. 16 radiance is equal to: Physical Units = Cal_Offset + (Cal_Slope x Level 1.5 Pixel Count) expressed in mWm-2 sr-1 ...
3
votes
1answer
67 views

How exactly does a single laser pulse from LiDAR act? [duplicate]

I'm trying to understand the behavior of a single laser pulse in a traditional airborne lidar. I understand that the multiple return values are representative of the surface that reflected the ...
0
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0answers
21 views

GRASS: strange classification output and reject map from “i.maxlik”

I am trying to perform a supervised classification with "i.maxlik". I have three bands: 1) elevation (a dem); 2) reflectance (derived from Landsat ETM+ band4); 3) cumulative solar radiation (derived ...
0
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0answers
66 views

Calculation of Land Surface Temparature Using Landsat-8 Band 10&11

I had calculated land surface temperature (LST) from landsat-8 TIR data and found that the maximum temperature found in the current fallow land instead of built-up land. However, previous research has ...
4
votes
1answer
230 views

Difference Between Radiometric calibration and radiometric correction

I am new in remote sensing field. I sometimes got confused when I read about image pre-processing. Can someone please elaborate to me the difference and some example methods to do radiometric ...
0
votes
0answers
99 views

Evapotranspiration in SEBAL and ERDAS IMAGINE?

I am estimating ET from Landsat 7 imagery. I followed the SEBAL manual by Prof Allen and it has really been helpful. I have run through the model in Erdas Imagine and the metric spreadsheet and have ...
3
votes
1answer
299 views

Radiometric calibration of Sentinel-2 products

How can I calibrate Sentinel-2 products, to extract the reflectance? I've downloaded few Sentinel-2 products from https://scihub.copernicus.eu/s2/#/home, and opened them with SNAP but its radiometric ...
0
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1answer
58 views

How to aggregate/resample a higher resolution image to coarser resolution using defined threshold?

I've got a 30 m classification image and i'd like to convert it to 500 m resolution using a user-defined threshold value. Basically what i'd like to accomplish is similar to using the Resample tool ...
3
votes
0answers
178 views

Import GPS SINEX (for velocity analysis) into Sarscape or processing with others software

I try to import GPS snx. into Sarscape 5.2 (use GPS Import tool) and getting error 115) ) gps_type : [sinex] 116) ) generate_kml : [OK] 117) ) generate_shape : [OK] 118) ) ...
2
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0answers
35 views

How to determine Visibility Map for Atmospheric Correction

As per Grass wiki: https://grasswiki.osgeo.org/wiki/Atmospheric_correction the atmospheric correction could be done using a visibility raster in conjunction with an elevation raster. With regards to ...
4
votes
1answer
280 views

Random Forest land cover classification in ArcMap?

I am an undergraduate student working with a very large data set (to me), and who has NO experience with R, but is fairly comfortable with ArcMap. I have about 60GB of 8band 1m satellite imagery of ...
0
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0answers
58 views

How to correctly parse MODIS QA layers?

I'd like to correctly parse the MOD13Q1 VI Quality layer (see Table 2 in "layers" here). For this, I'm trying to follow Example 1 from this tutorial (page 10). I'll illustrate my problem with a pixel ...
0
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1answer
117 views

How to remove shadows from high resolution imagery (IKONOS 1M)

I have dataset imagery comes from IKONOS satellite, the dataset contains "imagery with 1m resolution - metadata - rpc file", the metadata file contains the information about "Sun Angle Azimuth - Sun ...