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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0answers
64 views
+50

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 ...
1
vote
2answers
72 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
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1answer
60 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
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0answers
51 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
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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
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2answers
78 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
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0answers
48 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
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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
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2answers
197 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
57 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
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0answers
17 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
80 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
68 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
99 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
46 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
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0answers
33 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
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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
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2answers
78 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
76 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
85 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
91 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
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0answers
37 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
45 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
175 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
296 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
55 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
74 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
448 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
159 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
146 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
475 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
58 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
104 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
196 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
176 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 ...
3
votes
1answer
87 views

How to interpret MOD44B 8-bit quality layer

I have 15 annual MOD44B (vegetation continuous field) HDFs for 2000-2014, working in Arcmap 10.2. Each contains several bands. The two I'm concerned with are "percent tree cover" and "quality." The ...
2
votes
1answer
47 views

Rigorous geometrical models for InSAR imagery?

I'm looking for rigorous geometrical models for InSAR imagery. I'm familiar with the rigorous models for SAR images, but I don't know the model for InSAR. I searched through the internet, but I didn't ...
3
votes
3answers
258 views

What should come first-Radiometric calibration or co-registration?

For a pair of images,in the pre-processing of satellite images, which step should come first- Radiometric calibration or co-registration?
1
vote
1answer
140 views

Enhanced Vegetation Index Value

Can enhanced vegetation index have values greater than 1? I am using the ENVI software to calculate enhanced vegetation index (EVI) of a hyperspectral image and my EVI value range was from 0 to 1.9. ...
3
votes
3answers
125 views

Multi Temporal Images

I am new to remote sensing, so I would want to clarify my understanding of the meaning of Multi Temporal Images. As far as I understand, multi temporal images are multiple images of the same scene ...
1
vote
0answers
111 views

Format of SAR images

What is the format in which SAR images are stored? By format I mean when a SAR captures an image, it gets saved in what format? jpg? png? tiff? or there is some other special format? Is there a ...
0
votes
0answers
52 views

How to get multi-temporal InSAR data?

I am very much new to InSAR data. At the moment, i'm stuck at this website https://ursa.asfdaac.alaska.edu. Just wanna know, is it possible to get multi-temporal InSAR data for a particular region ...
3
votes
1answer
85 views

what does it mean to store cross products in SAR product data file?

I'm reading the UAVSAR data format For definition of two types of file we have: MLC files (.mlc): calibrated multi-looked cross products, floating point format, three files8 bytes per pixel, ...
3
votes
1answer
226 views

What is multilooking?

Today I found a video on youtube for multilooking the data with NEST (Next ESA SAR Toolbox) and it seems that it produces square pixel out of rectangular SAR pixels. Does it operate as simply as ...
2
votes
2answers
223 views

Deciding variables for unsupervised image classification?

The results of an unsupervised image classification may vary A LOT depending on the variables you use from the beginning. These are the variables for the tool in ArcGIS:number of classes, minimum ...
0
votes
1answer
49 views

aerosol optical depth

i want to extract aerosol optical depth on land using modis it seems like I need a value from one of these parameters between Corrected_Optical_Depth_Land and Corrected_Optical_Depth_Land_wav2pl but ...