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
25 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
votes
1answer
104 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
votes
1answer
219 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
22 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
106 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
51 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
63 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
votes
1answer
45 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
votes
1answer
119 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 command-...
-1
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1answer
109 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 step-by-...
2
votes
1answer
37 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
30 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
11 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
1k 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
vote
1answer
38 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
35 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
97 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
241 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
138 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 procedures ...
0
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1answer
102 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
votes
1answer
50 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
votes
2answers
102 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 (https://lpdaac.usgs.gov/dataset_discovery/modis/modis_products_table/...
3
votes
2answers
128 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
votes
2answers
65 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
vote
1answer
87 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
185 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
209 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
144 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
votes
0answers
130 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
votes
2answers
434 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
74 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
vote
1answer
186 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
votes
0answers
43 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 (cm-...
3
votes
1answer
80 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
votes
0answers
26 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
votes
0answers
95 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
474 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
145 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 ...
4
votes
1answer
579 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
votes
1answer
82 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
192 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
votes
0answers
42 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
407 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 ...
4
votes
2answers
142 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
votes
1answer
145 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 ...
1
vote
2answers
101 views

Creating a mosaic from multiple Landsat scenes on Qgis

I wish to produce a large image. As a base use cloud free regions of multiple Landsat images. I wish to keep the bands and be able to work with the generated mosaic just like a "normal" Landsat image. ...
0
votes
1answer
65 views

Source for high resolution satellite images

I am looking for high resolution imagery of the Nicobar Islands. Ideally 3 images (2004, 2005 and 2014/15). My budget is 1500 USD. Which image providers would you advice? Until now I have only worked ...
2
votes
0answers
65 views

TIMESAT seasonality data (MODIS EVI)

I am trying to get seasonality parameters from MODIS EVI (MOD13Q1) for Indonesia. I have loaded data from 2013-2015, but the plotted time-series is shifted from what I expect. Indonesia has rice-...
3
votes
0answers
34 views

Guide to aerial or space data types and availability

I am overwhelmed by the variety of types of satellite and aerial data (images?) available online. For example, at the USGS Earth Explorer data page, I see AVHRR; CEOS;Ikonos and OrbView; EO-1; GLS; ...
2
votes
2answers
91 views

Regarding Landsat 8 QA image color

As par the USGS page explaining the 8 bit quality image in following link: http://landsat.usgs.gov/LandsatLookImages.php Water is represented by bit 3 [Translated to color range (8 -15)] and Snow/ ...