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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2
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2answers
37 views

How to atmospherically correct Landsat 8 data?

What is a simple way to atmospherically correct Landsat 8 data using Erdas 9.3 or ArcGIS 9.3?
0
votes
1answer
15 views

Semi Automated Classification plugin (QGIS) error when trying to create ROI

When I try to create a new ROI through Semi-Automated Classification plugin (SCP) for QGIS, I keep getting a message saying: "It appears that SciPy is not correctly installed. Please, see this page ...
3
votes
1answer
257 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 ...
0
votes
1answer
21 views

comparison of atmopsheric correction methods

I have noticed that dos methods for atmospheric corrections are in the section of radiometric correction (i.toar) on grass gis.Does that means that dos is a method doing radiometric and atmospheric ...
2
votes
2answers
249 views

Spectral profile (z-profile) viewer for ArcGIS

I have multilayer raster with 6 bands. Is there a way to select one specific pixel and to display the z profile (the values of each band) for this pixel as a chart or table? I am looking for a tool ...
1
vote
0answers
19 views

NDVI calculation using ArcGIS 10.1

i have to derive NDVI from Landsat 8 image.. I used the following equation from landsat website with band 5 and band 4 using ArcGIS 10.1 Conversion to TOA Radiance OLI and TIRS band data can be ...
10
votes
1answer
1k 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
1answer
29 views

Landsat Surface Reflectancce product Python packages

I have to work with numerous Landsat surface reflectance product that I downloaded from http://landsat.usgs.gov/CDR_LSR.php. The product comes with a QA data with information on clouds and shadows ...
3
votes
0answers
17 views

Should Endmembers be Normalized for Linear Unmixing?

In biological spectral microscopy, the standard in the field is to use normalized endmembers in linear unmixing algorithms. In most cases, the endmembers are normalized to the maximum value. I have ...
1
vote
1answer
334 views

Masking clouds with Fmask

I have been trying to mask clouds with the quality control band with landsat 8 imagery. The problem I continue to run into is that the quality control bands mistake tops of buildings and concrete as ...
0
votes
0answers
8 views

How do you digitize an ROI in envi 5.2?

Is there a way to digitize an ROI in ENVI 5.2 that is larger than the area shown in the viewer? I'm setting up labs for an intro to RS class, and the next step is to subset the image to get rid of ...
2
votes
3answers
782 views

Failed to create signature file

I need some help, because I've no clue how solve this issue the exercise that I'm trying to perform. The point where I'm stuck is 4. "Create signature file as LandsatCompS.sgs". I've done what it ...
3
votes
0answers
40 views

How to compute NDSI in ArcGIS for Desktop?

How do I compute a Normalized Difference Snow Index (NDSI) in ArcGIS's Raster Calculator? I have a Landsat 8 scene (hdf4 format) that contains derived surface reflectance band-by-band. Each band is a ...
1
vote
0answers
27 views

Which preprocessing comes first for pansharpened imagery- atmospheric correction or orthorectification?

For pansharpened imagery, what preprocessing method to do first- is it atmospheric correction or orthorectification? From my readings, it seems the former but the rational polynomial coefficients or ...
1
vote
1answer
88 views

Performing image segmentation in QGIS?

I have been trying to learn to work with QGIS (open-source GIS software) through some tutorials available online for classification of image for land cover. These tutorials used a dataset from Landsat ...
3
votes
0answers
32 views

From Landsat spectral radiance (W/m2*sr*µm) to Global horizontal irradiance (W/m2) for mere mortals

We are working in a solar energy project to locate potential sites for solar panel farms. We are using the Landsat 7 panchromatic band to derive radiance with GRASS using i.landsat.toar (W/m2*sr*µm ...
0
votes
0answers
41 views

Image formats to use for land cover classification in Python? [duplicate]

I am supposed to classify images for different land covers or land uses in Python. I read somewhere that the spectral module of Python is required to do the processing of Hyperspectral image data. ...
0
votes
1answer
47 views

Creating raster depicting landcover/use change in ArcMap?

How would I create a conversion matrix in ArcMap 10.2.2 to display the changes between two rasters (Land Use Land Cover Maps)? I have produced Land Use Cover Change maps from temporal satellite ...
0
votes
0answers
40 views

Calculating climatological albedo using MODIS satellite images?

My question is based on the paper Using NOAA AVHRR and SPOT VGT data to estimate surface parameters: application to a mesoscale meteorological model. The authors have calculated albedo, surface ...
1
vote
2answers
59 views

Is it possible to split a picture taken with a regular digital camera into real spectral RGB channels?

I have no idea how the sensors inside a camera work. I know I can take jpeg and separate the R, G and B channels but I have no idea whether these channels are the real red, blue and green in visible ...
16
votes
4answers
4k views

Which remote sensing satellite is best used for vegetation extent mapping

I'm currently writing an assignment for my remote sensing class and while I think I have correct answer was wondering what people who do this stuff for a living think. The question is: which ...
0
votes
0answers
54 views

Identifying dwellings/homes from imagery using ArcGIS for Desktop?

I have a task where I need to identify dwellings/homes on property lots. The data that I have is an aerial image of the town, cadastre/property boundaries, land tenure information and land-use. I ...
0
votes
1answer
46 views

Understanding InSAR interferometry?

I understand that the result of InSAR interferometry yields a LoS deformation and if deformation in the vertical or horizontal is to be computed, it should require additional gps observations at the ...
1
vote
1answer
31 views

How to convert GOES-R (15) IR image from gray-scale to brightness temprature

How do I convert satellite IR images taken by GOES-R (15) from gray-scale to brightness temperature? We can download the IR satellite images, and read its RGBA values. But how can we convert this RGBA ...
3
votes
3answers
115 views

Atmospheric correction for pansharpened imagery?

In converting DN values to radiance as well as reflectance, do we use the same equations in raw satellite imagery for pansharpened products? I saw this DigitalGlobe technical note for DN to radiance ...
1
vote
0answers
45 views

SRTM DEM and satellite DEM fusion

I have a SRTM DEM and a DEM derived from satellite (Cartosat). Both the DEMs are registered perfectly. Now I want to carry out a DEM 'fusion' process to derive a higher quality output DEM. I am not ...
7
votes
3answers
252 views

Handling mountain shadows when classifying Landsat 8

I'm trying to classify some area in northern Mongolia using Landsat 8 satellite images from 2013. Since the recordings were made in winter, the sun is very low at the acquisition time. Therefore there ...
0
votes
0answers
25 views

I am looking for Thermal IR Photography with 1 m resolution?

I am looking for thermal IR photography with 1m resolution? It needs to be recent or maybe a company in western Canada that can fly a mission like this. Satellite or flown photos both work, I am just ...
2
votes
2answers
94 views

Feature extraction in remote sensing! [closed]

Which are the most common features in order to perform a supervised classification in remote sensing? Furthermore anyone worked with SAR features? Which are the most commonly used? Can anybody suggest ...
6
votes
4answers
544 views

Python resource for remote sensing? [closed]

I am looking for a good resource (MOOC, book, etc..) to teach Python for remote sensing applications. I am already familiar with http://www.rsgislib.org/ - are there any other resource out there for ...
1
vote
0answers
129 views

Importing GPS coordinates to extract multiple DN values in ERDAS

I have a set of GPS points (stored as a csv for now) and would like to import these points to ERDAS to find the DN values associated with each location. I am able to import a SHP to ERDAS but the ...
2
votes
1answer
18 views

STATION_ID of satellite images

My question might be simple but can someone explain to me the importance of STATION_ID to satellite images?If the sensor is the same(e.g landsat TM) for 2 images but the STATION_ID is different (MLK ...
19
votes
7answers
2k views

Machine Learning Algorithms for Land Classification

I am interested in learning what software exists for land classification using machine learning algorithms (e.g. k-NN, Random Forest, decision trees, etc.) I am aware of the randomForest package in R ...
1
vote
0answers
17 views

LULC using SAR data

I have a Geocoded SAR data with me. I have to perform LULC classification. I have been given a shapefile (vector data) with the different LULC categories of the region. The region is mainly composed ...
1
vote
2answers
144 views

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 ...
4
votes
1answer
68 views

What is NIR LiDAR?

Can LiDAR sensors collect near-infrared (NIR) data at the same time or does there need to be a separate NIR camera that is combined with the LiDAR data after collection? Blue Marble makes reference ...
1
vote
4answers
135 views

Automated Forest Change Detection

Using two different time of images in the same places. Can i develop an automated change detection for forest area? What / which are the suitable software to used?
1
vote
0answers
39 views

Effects of heterogeneous vegetation in mapping canopy cover using randomForest in R

I have a 5.8 m resolution satellite image (LISS IV by IRS-P6, in bands 4, 3 and 2) of a densely forested region in the Eastern Himalayas. My objective is to predict regions of canopy cover. Regions of ...
0
votes
1answer
43 views

When parametric classifiers fail?

In which situations are statistical assumptions (e.g. multivariate normal distribution within spectral classes) for parametric classifiers (e.g. maximum likelihood ) not valid for land-cover ...
1
vote
1answer
38 views

The stability of randomForest models after increasing predictor variables

With reference to the posts: Incorporating terrain data to predict canopy cover using randomForest in R and Random-Forest Classification of 10cm Imagery for species-distribution in R (no point-shapes) ...
2
votes
1answer
65 views

Incorporating terrain data to predict canopy cover using randomForest in R

This is a subjective question. Thank you bearing with me. I have a 5.8 m resolution satellite image (LISS IV by IRS-P6, in bands 4, 3 and 2) of a densely forested region in the Eastern Himalayas. My ...
2
votes
1answer
26 views

How to interpret BUFR descriptors

I'm processing BUFR products from Eumetsat and I would like to ask for your help about the following descriptors: 002028 SEGMENT SIZE AT NADIR IN X DIRECTION 002029 SEGMENT SIZE AT NADIR IN Y ...
-1
votes
1answer
22 views

How to create ASCII time-series files to make TSM_GUI in TIMESAT? [duplicate]

I would like to create TSM_GUI in TIMESAT, but as an input i have to choose ASCII time-series files, but I have only .tif images. How can i do that? Many thanks
3
votes
1answer
72 views

Remote Sensing Indices for urban expansion

Apart from NDBI, could you name a few indices for urban expansion? I have done some search on google but haven't found anything that could help me. Perhaps, What I'm interested is also: ...
4
votes
0answers
161 views

Which remote sensing satellite is best used for chlorophyll mapping?

Location of my research are reservoirs which have an area of 47 and 62 km2. I need a better image resolution than Landsat(Pan).
1
vote
0answers
31 views

Using NDVI values as covariate in survival analyses

I am trying to become more familiar with processing NDVI values in GIS. However, despite its usefulness, it seems to have some limitations. Namely, creating NDVI values across a large scale can be ...
1
vote
1answer
90 views

How to remove band from stack in ERDAS 2013?

I have a Landsat 8 scene where I have stacked 11 bands. I need to remove one band from the stacked layer. Is there a toolbox in ERDAS 2013 that allows me to take out a band? I am aware that ENVI ...
0
votes
0answers
70 views

QGIS Raster Calculator giving a NaN output

This is my first time using QGIS and I am trying to use it to generate NDVI maps from data captured by my UAV. However when I apply the NDVI formula in the raster calculator using my NIRGB image the ...
0
votes
0answers
180 views

NDVI from QGIS is giving me NaN values

When I use QGIS' "slope based VI calculation" for Landsat 8 IR and Red bands the resulting NDVI and TTVI maps are all NaN values. When I do the NDVI calculation using the raster calculator it looks ...
0
votes
1answer
56 views

Satellite Images for the Mediterranean Sea Oil Spill

I am looking to obtain free satellite images to detect oil spills in the Mediterranean sea. What sensors would be most appropriate for this task and where can I download this type of data?