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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7 views

Opendap automated download with Python in ArcMap

I want to use python to automate the download of satellite images from OpenDap. Any help would be very much appreciated? I did find a similar post here, but I have tried using this script and it does ...
0
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0answers
28 views

How to analyze Vegetation Index using Sentinel-1 SAR Imagery?

I am using the ESA open scientific data hub for Sentinel 1 SAR imagery (Interferometric Wide swath SLC VV polarization) and would like to know how to perform vegetation health analysis from this data? ...
10
votes
1answer
603 views

Multispectral image segmentation for natural-resources applications using R

R has the capacity for image segmentation, although all of the examples I have come across utilize a single band for the segmentation (example). I am interested in combining R's capacity for random ...
2
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1answer
35 views

MODIS temperature and NDVI data?

hope anyone could give me some hints here. I tried to download free MODIS data from their page(resolution 500m, 1km). Im interested in NDVI and temperature data. But when i load the hdf files into my ...
2
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0answers
20 views

Converting CDF file to NetCDF file to use in ArcMap? [duplicate]

This is a GIS question as well as a Remote Sensing question. I have downloaded CDF files from the ESA from MyEarth online and want to use them in ArcMap. In ArcMap you can Make NetCDF a Raster Layer. ...
0
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2answers
116 views

Satellites to retrieve UV bands

I want to retrieve some satellite images with UV bands,Bun I don't know which satellites are providing UV bands and We can freely download them? I have already downloaded Modis and Landsat images,But ...
19
votes
3answers
4k views

How to produce high-resolution DEMs from new Sentinel-1 data?

This is a general question relating to the new Sentinel-1 data. I'm interested in the potential for using this data to create high resolution DEMs in GIS (I use QGIS), to investigate archaeological ...
2
votes
2answers
478 views

Classification, Change detection and NDVI Using (landsat2 MSS), (landsat5 TM), (Landsat7 ETM+) and (Landsat8 OLI)

I have 5 Landsat images for the same study area. One of them in 1975 (Landsat 2 MSS), two in 1985 and 1995 (Landsat 5 TM) and one in 2005 (Landsat 7 ETM+) and the last one in 2014 (Landsat8 OLI). I ...
2
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2answers
819 views

How to perform an accuracy assessment in eCognition?

How to do accuracy assessment of classified images in ecognition? I have done the image segmentation for Worldview-2 image. Then, I have processed for classification for class names (e.g ...
3
votes
1answer
60 views

Removing cloud from Sentinel 2A imagery?

I would like to use sentinel 2A imagery to look at canopy cover in Northern Vietnam. The only problem is that ALL the recent images have large amounts of cloud in the area I want to look at. Is it ...
2
votes
0answers
49 views

Calibration error for Sentinel 1 image in SNAP toolbox

I am working with a Sentinel 1 SLC IW image (VV+VH) and trying to calibrate the data in the SNAP toolbox. However, it keeps returning the error "cannot construct data buffer" Does anyone have any ...
1
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1answer
34 views

Getting latitude-longitudes from tiff and world file

I have downloaded Version 4 DMSP-OLS from here, which is a bunch of tiff files with their world files. I would now like to crop an area specified by bottom left and top right lat-long points. I ...
2
votes
1answer
243 views

applying savitzky golay filter to modis ndvi data

I want to smooth the ndvi MODIS 16 bit integer data .tif for LULC classification . i have timesat 3.1 software on windows but i don't how to apply the SG filter . i am not that good in programming . i ...
0
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0answers
13 views

MODIS MCD43A3 albedo product: good quality observation and fill value at the same time?

I’m using the MODIS MCD43A3 albedo product on one of my projects. I only used the good-quality values determined based on the BRDF_Albedo_Quality band recorded in the associated MCD43A2 product. ...
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0answers
23 views

Spatial Resolution (Scanning Precision)

I am using Landsat_7 image and details is pasted below: - Date of acquisition: January 2001 -Pixel size: 25 m -Spectral bands:  Band 1: Blue 0.45-0.52 µm  Band 2: Green 0.52-0.61 µm  Band 3: Red ...
3
votes
1answer
435 views

Applying pixel reliability mask to time series MOD13Q1

I am working with a 23-band GEOTiff in which each band is a 16-day MVC MODIS NDVI image. The MODIS .hdfs include a "pixel reliability" image with the following values: [-1]: Fill/No Data-Not ...
1
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1answer
23 views

Remove raster pixel in R

This is the 32 year trend NDVI (raster data) I would like to remove the green grids data by using R (the green pixel value is larger than 0.03) and this one is R code that i use but i cannot ...
0
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1answer
71 views

Remote sensing accuracy assessment - McNemar`s Test

I would like to know how you determine the f12, f21 parameters for use in the McNemar`s test when for example I have two confusion matrices such as below: (where f12 = number of cells misclassified ...
2
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0answers
26 views

Negative reflectance values after topographic corrections (cosine correction and modified Minnaert correction)

I am trying to manually correct the surface reflectance values of some Landsat 7 and 8 images. I'm using Minnaert modified method, which uses the cosine correction as one of its inputs (see below the ...
4
votes
2answers
129 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 ...
8
votes
2answers
2k views

What are LiDAR returns?

Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system.
2
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1answer
38 views

Imagery Band order for Natural and False color imagery

I have an image which has had its band ordering rearranged, giving it a weird false color. I wanted to change it back to a natural color, so I used GDAL and through trial and error got the bands ...
4
votes
1answer
61 views

Detect cattle on high resolution satellite images

I have no deep experience in remote sensing. I would like to know if it might be feasible to detect cattle (i.e. a single cow or bull) from a high resolution satellite image e.g. Worldview 3 with a ...
1
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0answers
11 views

What indices could is use for coastline extraction using rapideye imagery

I am currently writing a proposal to get RapidEye imagery for my master thesis. In this proposal I am trying to explain what I am doing. Except NDVI/NDVI-RedEdge and NDWI, can anyone suggest some ...
1
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1answer
10 views

MODIS emissivity extraction

I am doing validation of 40 Landsat images.now I need two spectral emissivities of the 8-day MODIS land surface temperature and emissivity product (MOD11A2).and I have to extract emissivities for ...
1
vote
1answer
22 views

Are my reflectance values of bands in range and what does DRA in GIS 10.1 do to bands?

I have done the TOA correction to red and near infrared bands using raster calculator and calculated NDVI from lansat 8 image. The NDVI range came as : upper range=184 and lower range=(-235). When I ...
2
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0answers
28 views

MODIS Imagery Orthorectification (Open Source)

I am looking for an open source free software/tool for orthorectification/Geometric terrain correction of MODIS imagery. I have looked at ESA (European Space Agency) SNAP but this sensor type is not ...
1
vote
1answer
163 views

Are there any good MOOCs (online training courses) for remote sensing?

I'm looking for a MOOC (Massive Open Online Course) for remote sensing. Does anyone know if there is currently running or if is there any change to begin in the future any MOOC for remote sensing?
0
votes
1answer
25 views

Methodology for Image Classification (beginner) [closed]

I'm a beginner with remote sensing and have the task of creating a land use/land cover map of a region in India from IRS imagery. I've never performed an image classification before, although I do ...
0
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0answers
28 views

Free satellite images for academic purposes [duplicate]

Since the Landsat mission opened it's archive a lot of great scientific studies have been produced in the field of Remote Sensing. The Sentinel imagery from ESA is also thought to be open access ones ...
-2
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1answer
24 views

“First” and “Last” from Global Forest Change [closed]

What are the "first" and "last" rasters provided by the Global Forest Change data set?
0
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0answers
49 views

How to mosaic two ladsat images when they have different reflectance distribution value

I have two adjacent landsat-8 images from two different time, April and October. They have different reflectance value. While mosaicing these two does not seem to have matching histogram. I tried by ...
4
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2answers
68 views

Where / How to download Sentinel 2 Images

I need Sentinel 2 imagery of Nigeria, I signed up in Copernicus Scihub but typing Nigeria into the text box no results appear. I must be doing something wrong, how can be possible that they do not ...
3
votes
0answers
44 views

Classify image using segmentation analysis using QGIS and OrfeoToolbox

My first question on stackexchange (sorry for my english language)! I use stackexchange often to understand GIS principles and workflows. I wasn't able to find a answer. For this project we made a RGB ...
0
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0answers
24 views

Why rescaling disturbs Band Order of FLAASH derived Reflectance image?

I have derived Reflectance values (MS bands) by calibrating Landsat8 OLI using ENVI's FLAASH module. The outcome of the FLAASH derived Reflectance values are scaled by 10,000 (by default), The reason ...
1
vote
1answer
219 views

Maintaining spatial integrity of Matlab matrix with missing data

I am working with MODIS Terra imagery (MOD13Q1). I am currently trying to compute the autocorrelation structure of the pixels in an MODIS NDVI raster. The problem is that I have clipped the original ...
-1
votes
1answer
35 views

What resolution will be able to show visible changes on a parcel of farm land? [closed]

What resolution will be adequate (5m, 2.5m, etc) to show visible changes on a parcel of farm land? Each plot is typically the size of two football pitches. Details to detect: a) has the farm land ...
1
vote
1answer
55 views

Point otbApplication for python to the relevant OTB DLL's

I installed the latest OTB and Monteverdi on a Win 7 machine. Via osgeo4w I downloaded otbApplication for python, without any dependencies. Python, gdal, numpy scipy and so forth was custom build ...
0
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0answers
13 views

Facing “unknown sensor error” in using Alos Polsar 2 (Geotiff format) at ENVI 5.3

For calculation of Radar Backscatter for Alos 2 (2015) whit Geotiff format via ENVI 5.3, I faced following error: "The target file does not appear to be a valid sensor type" The question is; how ...
0
votes
1answer
69 views

Layer stacking Sentinel 2 imagery

Is it possible to layer stack all 13 Sentinel 2 bands or can I only layer stack those that are the same resolution (so for example the blue, green red and NIR bands). I have a very large area of ...
3
votes
1answer
167 views

ICESat/GLAS coordinate system conversion

I have to import ICESat GLAS14 product data into ArcGIS. I managed to export into an ASCII file the binary GLAS data using NGAT tool, but the coordinates system are in an uncommon format ...
3
votes
0answers
37 views

How to classify difference surfaces having almost similar Reflectance responses?

I am using ENVI 5.3 to classify a Region of Interest clipped from Landsat 8 OLI. I have already performed calibration of my DNs by transforming it into Radiance and derived Reflectance image using ...
2
votes
1answer
442 views

Python script for dark object subtraction on Landsat 8 Imagery

Does anyone know of any python scripts that will allow me to conduct such a process? I am limited to open source software and have minor experience in Python.
0
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0answers
38 views

Layer stacking many images using Python and Erdas Imagine Spatial Modeler

I have downloaded huge amounts of Sentinel 2 data to cover a large area of the Himalayas and need to layer stack each tile. I have decided to use Python to do this using the LayerStack tool from Erdas ...
2
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0answers
19 views

ModelBuilder Iterations and Data Storage

OK, so here's my situation. I have a large series of rasters divided into two categories, let's call it Type A & Type B, a pair for each of a few hundred date/time snapshots. The date/time for the ...
1
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3answers
71 views

What preprocessing is required when using Landsat for LULC?

Can anyone help me regarding the what kind of image pre-processing techniques should be used for the landsat images downloaded from http://earthexplorer.usgs.gov/ to create land-use land-cover (LULC) ...
2
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0answers
12 views

Image sizes for VHR remote sensing image

I need to compare three or four different segmentation algorithms on very high spatial resolution remote sensing images, with a range between [0.31,1.00] meters/pixel. What image size could you ...
0
votes
2answers
55 views

Removing black background in ENVI

I am trying to compare two DEM products ASTER and SRTM v.3, but the ASTER has the black background which i think will interfere with my analysis. I don't have access to ArcGIS where I can do this ...
1
vote
0answers
10 views

Issues with using FLAASH on GeoEye data

I am trying to carry out a FLAASH atmospheric correction on radiometricaly corrected GeoEye-1 spatial image (working within ENVI). I am geting the wrong results from my FLAASH correction and belive ...
1
vote
2answers
218 views

Landsat 8 OLI Tasseled Cap Transformation Calculation ArcGIS 10.3

I need to calculate the TCT greenness for Landsat 8 OLI imagery and having a hard time finding a tool. All the python scripts I have found do not work and I am not experienced with Python at all. ...