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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3
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0answers
40 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
72 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
23 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
76 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
286 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
111 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
387 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
62 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
179 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
37 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
323 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
132 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
123 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
77 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
62 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
53 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 ...
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
81 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/ ...
0
votes
0answers
49 views

Generating outlines of islands using QGIS?

I have a (raster) satellite image showing islands. I wish to extract the boundary (shoreline). I tried a simple classification with just two groups (land and water). Unfortunately too many ...
0
votes
0answers
37 views

Using night/day-time LST product of MODIS?

I was confused with the night- and day-time bands of the LST product of MODIS. As I understood, these two bands are derived based on the zenith angle; more than 90 degrees for night-time LST, and less ...
1
vote
2answers
220 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. ...
1
vote
2answers
59 views

Function for hyperspectral rasters with 3 variables unexpected error

I am writing a script to extract vegetation indices from hyperspectral datacubes. One of the indices is the Triangular Vegetation Index for which I wrote the following function: TVI2 <- ...
0
votes
0answers
19 views

How to get the daily-air temperature of several months of the past years?

I really need to obtain the daily-air temperature for several months of 2011. In addition, the data I'm looking for must have the maximum spatial resolution of 1Km*1Km. Since, as I know, there isn't ...
5
votes
1answer
90 views

Loop NDVI calculations for hyperspectral datacubes in R

I am writing a script for the processing of different hyperspectral datacubes. The datacubes contain flight lines that I've recorded with a UAV. In total there are 10 flight lines that need to be ...
0
votes
1answer
16 views

Rectifying a Tiff Given One Corner Coordinate

I'm trying to rectify an image that I don't know much about other than the coordinate of the southwest corner, which I was able to pull using ExifTool. Is there any programming solution to ...
2
votes
0answers
69 views

16-day-MODIS NDVI values seem to be wrong compared to my soil moisture ground data!

I'm using MOD13Q1 product of MODIS for estimation soil moisture. As I know, this product is made up of the maximum value of NDVI of each pixel over 16-day calculated NDVI values. The problem is that ...
3
votes
2answers
108 views

Atmospheric correction of Landsat images

In satellite imagery, isn't cloud removal supposed to be performed while atmospheric correction? My question arises from the fact that even though these Landsat images are atmospherically corrected, ...
1
vote
1answer
51 views

stack 10 modis ndvi geotiffs and scale them by 0.0001

I have 10 geotiffs Modis ndvi named 2005.tif ... 2014.tif I want to stack them all and create timeseries. i know how to do that, but the stacked images still need scaling by 0.0001. how can i bulk ...
1
vote
0answers
34 views

qgis Semi automatic classification pluggin how to add text to rows in attribute table

I want to use a previously created shapefile as Training shapefile in the semi automatic cassification pluggin. Therefore i added 4 fields to this shapefile: Macro_ID (int), MCl_info (text), Class_ID ...
3
votes
1answer
37 views

Is a photo of an infrared slide taken in a light box a digital Infrared image?

Many years ago we received many aerial infrared images. They were developed on transparent film like a slide but much bigger - 20cm x 35cm. If I now take a digital photo of these images, are they real ...
1
vote
2answers
84 views

Improves performance on R working with raster files

I´m trying this code to look for NA and negative pixel values and replace it for 0. But it´s too slow. Any tip for improve the performance of it? "all.files" is a list of address of the images. "r1" ...
3
votes
1answer
80 views

How to calculate the Scattering Matrix for a Sentinel-1 image

How can we calculate the elements of the scattering matrix (Spq with p and q being the transmit/receive polarizations), for a Sentinel-1 image? Does the image have to be in a Single-Look Complex ...
2
votes
0answers
88 views

Calculating Aerosol optical thickness from Landsat 7

EDIT I have added question down I am reading one paper and I found method to retrive AOT from landsat 7 image This should be simplifield equation, because they assumed observation zenit as 0. Than ...
0
votes
1answer
96 views

how to calculate summary statistics and produce line plot for daily MODIS LST quality bands

I have a raster stack (numpy 3d array) of daily MODIS LST quality bands. The quality bands have pixel values that correspond to the quality of the LST data in each pixel. For example, 2 = no data ...
0
votes
0answers
38 views

Accuracy assessment in change detection (satellite imagery)

What are some methods for assessing the accuracy of change detection, when performed on satellite images? From whatever study I have done so far, comparison with ground truth is suggested but mostly ...
1
vote
0answers
46 views

How to extact very narrow water linear features from GeoEye-1 image

I need to extract beaver channels from a GeoEye image (attached image). What is the best approach to automatically delineate such very narrow and not very sharp water features?
4
votes
2answers
181 views

Sentinel-2A: Begin of operational period?

This also might be of interest here, as it is an important data source: When does Sentinel-2A finally become operational and deliver images regularly? I tried to find information on that, but ...
6
votes
2answers
311 views

Landsat8 DN to TOA Reflectance (minus values)

I'm learning how to perform atmospheric correction manually, hence not using the automated methods available in ENVI metadata (band 1) for my Landsat 8 scene is as follows; RADIANCE_MULT_BAND_1 = ...
1
vote
2answers
57 views

i.landsat.toar not working and returning error [duplicate]

First time using grass. I need to convert DN to reflectance. Imagery -> Sat. images tools-> i.landsat.toar. But when I add raster name. I get error. Im using landsat 8 images WARNING: WARNING: ESUN ...
0
votes
1answer
80 views

Fractal Net Evolution Approach (FNEA) Citation

I've been looking for some original source to cite for FNEA (Fractal Net Evolution Approach), instead of just citing eCognition. Does anyone know of a paper on the origin of FNEA? My searches just ...
3
votes
1answer
516 views

SAR - Using the Intensity or the Amplitude for the classification

In a Sentinel-1 Level 1 Ground Range Detected SAR data product, Intensity = Amplitude * Amplitude. Should the intensity image or the amplitude image be used for radiometric calibration when using ...
2
votes
1answer
179 views

Is possible to merge landsat 8 with High Resolution Satellite Imagery?

i have landsat8 and High Resolution Imagery (1m) in the same study area, is possible to merge them to get one imagery so that i can take advantage of the accuracy satellite imagery.
2
votes
3answers
159 views

Search and concatenate Landsat bands with Python

I have a number of Landsat geotiff (*.TIF) file in a folder. The problem is simple, I need to search certain Landsat bands from that list and make a composite tif image. I am using Orfeo Toolbox's ...
7
votes
2answers
514 views

How to download MOD16 (Modis Evapotranspiration) image?

I use a 'R' script for downloading MODIS imageries. However, it doesn't give MOD16 product. I could neither find the MOD16 product in earthexplorer website. Though the desired product is available at ...
0
votes
0answers
59 views

Pan sharpening of World View 2 image

I want to pan sharp world view 2 multispectral data its panchromatic band using HCS resolution merge tool in erdas imagine, can any one guide about which resampling technique(Nearest neighbour, ...
2
votes
0answers
67 views

GIS or Remote Sensing technique to map sub-surface features?

I am trying to delineate agriculture tile drainage in Midwest. Does anyone know of any GIS and/or sub-surface remote sensing techniques to detect tiles/objects buried in shallow depth of soil? Does ...
3
votes
2answers
106 views

How to remove bounding box extents based on reflectance values of the image of Landsat8 by using R programming

I have taken the reflectance image from Landsat8 bands. Now the extents of bounding box showing negative values , to proceed to my next level of the process i need to remove this negative values and ...
0
votes
0answers
23 views

Image ID Landsat8 in SCP plugin

I have tried to classify the land with SCP plugins. how do I get IMAGE ID in LANDSAT8 as in the image below.
0
votes
1answer
215 views

Calculate NDVI with converted canon sx260 hs

I have converted my canon sx260 hs so it can capture NIR part of specter. Can anyone tell me how can i calculate NDVI now? My guess is that on the blue channel is now NIR value and Green ...
2
votes
1answer
208 views

How to handle MOD13Q1 NDVI Product Quality Assessment(QA) flags?

I am working on MOD13Q1 NDVI Product and i want to apply Savitzky Golay filter for smoothing Ndvi time series using Quality Assessment(QA) flags. I studied MOD13Q1 NDVI help file and found that ...