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
votes
2answers
229 views

LANDSAT Image classification and open source solution(s)

I have some experience with ERDAS IMAGINE in doing some supervised/unsupervised LANDSAT imagery classifications and now find myself in the position of needing to do the same but without the access to ...
1
vote
4answers
102 views

Looking for simple software to compare two Landsat Images

At uni I used ERDAS imagine to view two rasters at the same time and it had various viewers for comparing them. I'm looking for something that has a slider so that I can see the differences between ...
2
votes
0answers
34 views

“Back calculating” to quantify the “atmospheric effect” of water vapor or other gases in a “corrected” hyperspectral image using QUAC?

I know that when using FLAASH in ENVI, you can produce a water vapor map (caveats considered) from your atmospheric correction. My question is if it is possible to "back-calculate" a water vapor map ...
0
votes
0answers
43 views

Masked data included in ISODATA classification computations?

I am using ENVI to mask NDVI MOD13Q1 images using the "pixel_reliability" raster included in the MOD13Q1 hdf. All instances of cloud cover (pixel_reliability=3) have been masked (=0). I have applied ...
3
votes
1answer
98 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
52 views

Load a .sav file in ENVI

I have a 23-band .sav file that I need to load in ENVI. The 23 bands are 23 time points of MODIS NDVI data. I ultimately want to run a classification on this data. I have been using Data Manager to ...
1
vote
0answers
36 views

Distinguish between the types of cultivated crops in remote sensing

I recently produced map of LULC but there is the difficulty of distinguishing between the types of crops. Is there a method to distinguish between the types of cultivated crops such as wheat, barley, ...
9
votes
5answers
1k views

Recommended programming language for remote sensing?

I am beginning studies that hopefully will lead to a long career as a remote sensing specialist. I am currently working with ArcGIS for some applications and learning ENVI for others. I have ...
0
votes
0answers
45 views

MODIS L1B to Reflectance

Could we convert MODIS L1B to reflectance data rather than using data product MOD09 (7 bands)? If can, may I know how to convert it? Is there any source, published paper, forums, or any modeler (.gmd) ...
1
vote
1answer
457 views

Help with gap mask filling and landsat 7 in arcgis 10

i have downloaded images from Landsat 7 ETM+ SLC-off with corresponding gap mask. which is the best method for using it with arcgis 10, i tried the mask and statistical method described in arcgishelp ...
1
vote
1answer
330 views

Reprojected MODIS NDVI has range from -32768 to 32767, expected -1 to 1

I'm new to StackExchange and to remote sensing. I am working with MOD13Q1 250m 16-day MVCs. My goal is to use NDVI time-series to classify cropping pattern and crop type, then link this data to ...
0
votes
1answer
300 views

EVI and SAVI indices for Landsat 7 and Landsat 8

I'm trying to run the indices Savi and EVI at landsat 7 & 8. About SAVI I read this from ESRI and explains very good this index. About SAVI I have a question, I will choose buy my self the L ...
1
vote
0answers
56 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 ...
3
votes
1answer
77 views

Calculate ground nadir line from PV coordinates

I'm using an API which returns a satellite's PVCoordinates (Position/Velocity pairs). {P(1036869.5330731269, 6546536.584960848, 9.892293545390519E-11), V(-9994.355195123433, 1582.9503539842497, ...
3
votes
1answer
167 views

Create DEM from cartosat stereo pairs?

I have two carstosat stereo pair images. All i need to do is to extract DEM from those. So, i tried it doing with OSGeo4W. but i didn't succeeded in it. So IS there any other softwares or opensource ...
2
votes
0answers
47 views

Is there any statistical method to proof if the method is suitable or not [closed]

I have recently done a phenological study using threshold method from MODIS NDVI images. But I'm suffered that I don't have any situ observation (ground truth) data to do validation. Is there any ...
3
votes
4answers
193 views

Some remote sensing tutorials [closed]

I could use some tutorials on remote sensing, but some books provided they are free, would be useful. To be specific, tutorials on ERDAS Imagine, ENVI and other remote sensing software, general ...
4
votes
4answers
673 views

Alternatives for ERDAS Imagine

I am having trouble with the ArcGIS 10.1 and ERDAS Imagine 9.2 license conflict. From what I found out it isn't that rare, but interestingly enough why is there such a conflict in the first place? ...
3
votes
1answer
47 views

Sample classification datasets?

I was looking for some publicly available ground data classification datasets, specifically, locations in e.g. latitude/longitude with a description of the land cover/land use, and a reference e.g. ...
3
votes
2answers
495 views

Are there Python packages for Landsat 8 processing?

While there are a number of python projects for MODIS acquisition and processing (pyModis and get_modis), I have yet to encounter a toolset for automating Landsat 8 processing in Python. There's ...
2
votes
1answer
49 views

Need information about the Envisat satellite

I am new to remote sensing and I want to know about sensor design of Envisat satellite. Can anybody help me or preferably direct me to some good references?
1
vote
1answer
229 views

How to do geometric correction of remote sensing data in R?

My challenge is to replace most of the remote sensing commercial tools with R code (I'm teaching assistant at the University and I would like to move to open source R code to show the added values to ...
2
votes
1answer
38 views

Question on how many ASTER per year ? per month?

How many scenes are there for ASTER per year ? From what I understand is that the temporal is every 16 days. So, some month it will have 2 and some months it will have one. Thanks.
4
votes
2answers
129 views

Zooming into landsat-8 produces pixellated view

I am working on a project were I am using LANDSAT 8 images for remote sensing. The issue that I have is that when I zoom into them the photo is pixellated. I can not see a thing. When I zoom out ...
14
votes
4answers
494 views

Is there a tool that performs automatic recognition of buildings?

I'm wondering if there is a tool, which takes a satellite map of a region, detects typical buildings and allows the user to review its result (check, whether the tool correctly identified the ...
1
vote
1answer
56 views

Finding Normal to a given point in ECEF coordinates

I have a point of reference called Ground Reference Point (GRP) given in Earth Centred Earth Fixed (ECEF) coordinates as given below: (1.4892e+6, 6.1102e+6, 1.0637e+6) (all distances in meters) I ...
5
votes
1answer
880 views

Atmospheric Corrections for Landsat 8 OLI Using Orfeo Toolbox

I am trying to correct some Landsat 8 OLI imagery using the Orfeo Toolbox Optical Calibration tool via QGIS. I've retrieved data from Aeronet as well as relative spectral response data for the OLI ...
0
votes
0answers
207 views

Top-of-atmosphere reflectance conversion with WorldView-2 images

I recently received a set of radiometrically-corrected dynamic range adjusted 8-byte WorldView-2 images. I want to convert to top-of-atmosphere reflectance and would like to use the FLAASH in ENVI 4.8 ...
8
votes
2answers
421 views

How do you explain that band width and relative spectral response of MODIS band do not match?

To define relative spectral response, I referred to EFFECT OF RELATIVE SPECTRAL RESPONSE ON MULTI-SPECTRAL MEASUREMENTS AND NDVI FROM DIFFERENT REMOTE SENSING SYSTEMS by David James Fleming, 2006. ...
0
votes
0answers
144 views

Atmospheric correction for RapideEye without atmospheric parameters

I'd like to perform an atmospheric correction of my RapidEye images but metadata do no include atmospheric parameters required to use the 6s algo implemented in the Orfeo ToolBox. Is there a solution ...
4
votes
2answers
232 views

What does MODIS data reflectance values (MOD13Q1) mean?

Several publications suggest filtering MODIS data (in my case MOD13Q1) prior to use. They recommended to filter out pixels having blue reflectance more than 10%, but what 10% here means? is it 10% of ...
2
votes
1answer
229 views

I need some more information on ASTER for time series analysis

See my previous post on ASTER I have a question about that I am not sure about. So, if I wanted to analyze 10 years or so, do I need to download each ASTER file for each year (e.g. 2003 ASTER, 2004 ...
-3
votes
2answers
128 views

How to derive soil water holding capacity from Landsat data [closed]

For estimation crop yields, I need some information such as Soil water holding capacity, potential evapotranspiration, crop types of the area, etc. For this purpose, I want to derive Soil Water ...
3
votes
2answers
526 views

Figuring out map scale when you know the spatial resolution of a Satellite Image?

I'm interested in figuring out how map scale and satellite pixel size (spatial resolution) are related. For example the TM or ETM+ has roughly 30m ground resolution, then, what could be the finest ...
8
votes
1answer
163 views

Most Effective Format to Manage Aerial Photography for Viewing Only

What is the most effective format to manage aerial photography for viewing in ArcGIS? I manage several datasets of Aerial Photography at a few different companies. I have backups of the original ...
1
vote
0answers
237 views

Question related with NDVI value on water

There is a surreal thing on my NDVI images. NDVI values on lake is ranging from -0.04 to 0.7. (The lake surrounded by forest and has freshwater). Theoretically, negative value of NDVI is correspond to ...
1
vote
3answers
89 views

What are the white grids at 9.6953038715817,98.576672019046 in Google map?

A friend asked me to help interpret the white grids at 9.6953038715817,98.576672019046 in Goole map. In satellite image the grids are connected to rivers flowing into the Andaman sea. Most of the ...
2
votes
2answers
1k views

Open source solutions for Landsat-8 mosaicing and correction?

I am familiar with the major commercial remote sensing packages (ENVI, IDRISI ERDAS, etc), but I haven't previously had the opportunity to utilize open-source solutions. I have a several new ...
0
votes
1answer
119 views

Using Mosaicking Images in Erdas software

Do you know any dissertation which has written about Mosaic briefly? I did the Mosaic for my Landsat images but i want to explain and write about but i do not know how and what shall i write about it ...
2
votes
1answer
822 views

Open Source Alternatives to Erdas ATCOR

I have been using Erdas ATCOR for atmospheric correction of ASTER imagery. What opensource options exist for atmospheric correction of ASTER Level 1B products? I'm primarily interested in converting ...
2
votes
1answer
103 views

Advice on learning Remote Sensing software? [closed]

Can you please advice me on which Remote Sensing software ? Which one is popular ? Which one is the least ? Which one is the easy to learn curve ? Pros and Cons welcome ?
3
votes
1answer
1k views

processing MODIS hdf files with gdal

I'm trying to open an MODIS file (hdf format) with gdal in a python script under windows OS. I use the HDF4 driver, as read at http://www.gdal.org/frmt_hdf4.html. But when I run it I got this error ...
1
vote
2answers
141 views

Where to download ASTER scene boundaries?

I am looking for a shapefile of ASTER scene boundaries for the Kansas and Oklahoma region. The attached screenshot from GLOVIS is what I'm after, except I need polygon footprints with relevant ...
1
vote
0answers
88 views

How to convert MODIS (Vegetation Continuous Fields - MOD44B) to (.img and hdr) in ENVI

Please can anyone help me to convert MODIS (Vegetation Continuous Fields) to (.img and hdr) formats? In ENVI, anytime i try using the MODIS conversion toolkit, a dialog box appears telling me to ...
0
votes
0answers
44 views

patch analysis and spatial statistics for Grid data

I have TerraSAR data (raster data) for settlement, I must show the large density building, medium and low density in the map. Is this possible in the spatial analysis or patch analysis? I look ...
8
votes
4answers
272 views

Looking for a web service for change detection

I'm looking for service that provides me a change detection service based on a database of remotely sensed data. Has anybody happen to know such a service? The service I am looking for is a geoportal ...
2
votes
2answers
310 views

How can I perform an inside clip on a raster file based on another raster file?

I have a raster file that I would like to use to perform an inside clip on another raster file. I have tried using the extract by rectangle tool, but it gives me values ranging from 3.40282e+038 to ...
0
votes
1answer
159 views

Is Terrain and Topographic Correction the same for Landsat8?

Landsat 8 L1 products are "Terrain Corrected", that said it means that are they already "topographically corrected", like both words are synonyms or you need to apply correction techniques as well? ...
3
votes
1answer
257 views

Questions regarding the processing of mosaic Landsat 8

Approximate Translation of Original Question: A question of theoretical and practical about the mosaic of satellite images. I have 3 different months of Landsat images, which need to accomplish the ...
6
votes
3answers
2k views

Best source for high-resolution satellite images free/low-cost?

I am doing a household survey in Kenya, and I need to ensure that my survey team visits every house within a given area. I've been going to google maps and right-clicking on roofs to get coordinates ...