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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1answer
10 views

Geomatica Wavelength Landsat 7

im working with Landsat 7 images and Geomatica Focus. I want to use the spectral plot to distribute the different wavelengths (spectral signature) of my image bands. In the tool(right click- > ...
5
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1answer
702 views

Download new SRTM 30 meters

I read about the new version of the digital elevation model at 30 meters (SRTM 30 meters), but I can not find from were I can download it. some sources: ...
5
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2answers
80 views

Retrieving heights of buildings using remotely sensed data (except lidar)

How can I get the height values of buildings from a certain sector a city without going into the field to collect data? Is there anyway to do via satellite imagery, SRTM, ASTER GDEM or any DEM for ...
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5answers
139 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 ...
1
vote
1answer
31 views

How to destripe the thermal band in SLC_off LandSat 7 ETM+ data?

I am working on a special study in one of my subject. My study would require me to extract land surface temperature each year for 2007-2014. Since LandSat 5 ceaseed to operate last 2011, my 2012-2014 ...
2
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2answers
508 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 ...
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0answers
32 views

Format of RAW LIDAR Data (ToF data)

I am doing a project where I need to simulate LIDAR data, and I am looking for specifications on how raw LIDAR data looks. I want the format of the data before it is translated to x,y,z coordinates ...
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0answers
35 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?
6
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1answer
128 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 ...
8
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3answers
5k 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 ...
3
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1answer
2k 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 ...
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0answers
17 views

how to generate metadata file for semi automatic classification plug in?

I am working on satellite images. The region I am interested in is only a fraction of the whole satellite images. My laptop slows down tremendously when working on the whole image. So I clipped the ...
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0answers
128 views

Empty raster returned after GRASS i.atcorr with Landsat8 data

I've searched at length on previous forums but no solution seems to work for me. I'm trying to run the i.atcorr module on GRASS (version 6.4.3 on a Macbook Pro, Mavericks OSX) with Landsat8 imagery. ...
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2answers
469 views

LANDSAT 8 i.landsat.toar error GRASS 7

I am a bit new to GRASS, but I have managed to get a lot of good work done thus far. However, the following error is really throwing me off, because I can't find any help anywhere for it. I am using ...
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3answers
2k views

Where to download 4 band NAIP imagery?

I seem to recall USGS Earthexplorer providing current and historic 4 band NAIP imagery over the last few years. It appears that these data have been migrated to the National Map. However, the ...
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0answers
41 views

LAG LiDAR Analysis GUI installation guide

Does anyone know how do I install LAG lidar Analysis Gui? LAG by arsf This is my situation: I'm using debian 8 test. I installed this library: boost (yes) * GTKmm (yes) * GTKGLextmm (yes) * GThread ...
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0answers
35 views

Is there an accepted model of refraction affects on aerial photography

As I understand it the changes in atmospheric density as light moves through the atmosphere causes the light to bend. That means that if you are trying to calculate the location of a point on the ...
5
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3answers
182 views

How to easily identify/classify coniferous forest from one date Landsat image?

I am pretty new in remote sensing and I am trying to identify/classify coniferous forest cover from single date Landsat scene. According to my preliminary web research I have these possibilities: ...
2
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2answers
54 views

Counting plants in aerial images using unsupervised classification?

I am relatively new to GIS and I have the following problem: I want to extract the number of plants per row in a crop land. I have and RGB mosaic from aerial images. I think that I could do an ...
3
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2answers
180 views

High resolution satellite

Can any one tell me from where I can buy commercial High resolution Satellite images for Biodiversity research ? I need some websites that sells these kind of images ?
3
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1answer
170 views

Pan sharpen Landsat 8 using Grass 7

I have followed this great tutorial on pan sharpening using Grass GIS 7 (I'm using beta 3). Everything in the tutorial seemed to have worked, but my final output is not as expected (pictured below). ...
3
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3answers
1k views

NDVI image value changes from -1 to 1 in ENVI to 0-255 in ArcGIS Desktop and ERDAS Imagine?

When i open NDVI image in ENVI, its value is still within the range (-1 to 1). But when I open this NDVI image in ERDAS and ArcGIS Desktop, its value is 0-255. What does it mean? Is the NDVI ...
6
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1answer
74 views

Confidence in pan-sharpened classification?

I pan-sharpened one Landsat Image on ERDAS using the resolution merge resource, with brovey transform and nearest neighbor techniques. But I was told that in terms of land-use classification, it would ...
3
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1answer
344 views

Calculating NDVI using Landsat ETM+ band values

I have sample points (shape file converted from a .xls file which contains XY coordinates,nnx,nny and canopy density) and a landsat etm+ image. First I applied 'SpatialAnalyst Tools>Extraction ...
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1answer
29 views

i.landsat.toar doesn't Work With Band 6 of Landsat 7 in Grass 7

I'm facing an issue when running i.landsat.toar with a Landsat 7 image, here's the list of files: LE70010752014040CUB00_B1 LE70010752014040CUB00_B2 LE70010752014040CUB00_B3 LE70010752014040CUB00_B4 ...
3
votes
1answer
64 views

It is possible to verify landsat reflectance values?

My question is really wide today, as I am still beginner in Remote sensing. I´ve asked a GRASS programmer to prepare for me Landsat reflectance values from raw DN values (1 scene per year from 1987 to ...
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1answer
29 views

Using Quality Control process for MODIS Leaf Area Index?

Anyone can help in explaining how I can apply Quality Control (QC) for MODIS Leaf Area Index (LAI) to extract the valid pixels of LAI using ArcMap?
2
votes
2answers
94 views

Remote sensing data for different scales

I'm looking for different satellite data concerning different scales. The first one I'm looking for is remote data for soil sealing and water bodies at a scale of 1:30,000, could be generally ...
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0answers
189 views

problem of using TIMESAT to processing MODIS NDVI

I want to use TIMESAT software to analyse time series MODIS NDVI data. Firstly, I use MRT tool to mosaic,subset and project MODIS NDVI data and output data as GEOTIFF format, and save as ENVI standard ...
0
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1answer
118 views

QUAC atmospheric correction for Landsat-8 (ENVI 5.0)

I try to realize QUAC atmospheric correction for the band 4 and band 5 of Landsat-8 in ENVI5.0. This version doesn’t support Landsat8 (doesn’t have parameters of Landsat-8). At the first step I glued ...
0
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2answers
31 views

MODIS product MCD43A3 stating 16 periodicity but when downloadad I have files every 8 days

I'm downloading the MODIS derived Albedo 16-Day L3 Global 500 m resolution product. I expected to have a dataset for dates every 16 days. Instead I have datasets every 8 days as can be seen in the ...
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1answer
44 views

Customize rules in Random Forest for tree species classification

Is it possible to customize the rules in Random Forest algorithm for tree species classification? all the integration or customization of rules in random forest algorithm is done in medical field, ...
2
votes
1answer
339 views

NDVI time series in R — how do I create a time series object from a data frame?

I am doing a time series analysis of NDVI using the bfast package in R. Bfast requires a time series (TS) object. I have successfully created a data frame with the NDVI at various point locations ...
6
votes
4answers
1k views

Seeking alternative to 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 I do not understand why there such a conflict in the first place. ...
7
votes
2answers
172 views

Methodology for Hansen classification of Global Forest Watch?

I have just discovered amazing Hansen´s classification about forest loss and re-growth, available at http://www.globalforestwatch.org/, published in Science, 2013 as: Hansen, M. C., Potapov, P. V, ...
2
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2answers
64 views

Remove clumps of pixels in R

I would like to remove isolated pixels (or clumps of pixels <9) from my raster image. library(raster) # create some raster data r <- raster(ncols=12, nrows=12) set.seed(0) r[] <- ...
3
votes
1answer
195 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 ...
2
votes
1answer
44 views

How to write every raster from a list of rasters?

I have created a list of rasters - "norm" and run a several loops. Now I would like to write every created raster from "norm" (containing 1 layer) into one raster, having its specific name. # I can ...
0
votes
2answers
107 views

landsat 7 images

I want to work with landsat 7 images for land cover and NDVI evaluation. There are strips in the landsat images, and I don't know how to remote them. I have learned methods for gapfill but I don't ...
2
votes
1answer
117 views

Spot 6 - Reflectance calibration

I have a Spot-6 image and the metadata contain 9 values of SUN_ELEVATION (BottomRight BottomCenter BottomLeft CenterRight Center CenterLeft TopRight TopCenter TopLeft). I've used before Landsat and ...
1
vote
4answers
88 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?
2
votes
3answers
2k views

Atmospheric correction for Landsat 8 in ERDAS?

I am attempting to run some classification on Landsat 8 imagery, however, I need to perform atmospheric correction on the images in order to reveal true spectral signatures. I am using ERDAS, and the ...
4
votes
1answer
111 views

How to import multiple stacked raster images in R?

I have (I suppose) wery easy and silly question but I can´t really find my answer... I would like to import all multiple mosaic rasters (each mosaic is composed by 7 layers) from indicated folder into ...
1
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0answers
34 views

ENVI: Postclassification, remove pixels of certain size

I did a classification over multiple Landsat imagery in ENVI 5.1, which turned out not too bad (ice and snow in Cyan in the picture below). Now I am about to do a postclassification to filter out ...
4
votes
0answers
54 views

How do I open MOD17A3 in ENVI such that it is properly georeferenced?

I am using ENVI 5.1 on Windows 8. I am trying to open a MOD17A3 (MODIS Net Primary Productivity standard product - L4) .hdf file which I downloaded from the USGS website. I am still a beginner at ...
2
votes
1answer
119 views

Java packages for landsat 8 processing?

I am looking for the same packages as outlined in this question - Are there Python packages for Landsat 8 processing? except that I want these in Java. Any Open Source packages out there that can do ...
3
votes
1answer
323 views

how can i correct atmospherically landsat 8 images?

I am trying to correct atmospherically an image from Landsat 8 with 6s model from grass 7 and 6.4. Because there are no parameters for Landsat 8 yet, I am trying to give parameters from Landsat 7 ...
10
votes
1answer
650 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 ...
10
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1answer
154 views

Automated detection of tracks

Given an area with depressions in open area from; say all terrain vehicles driving on soft surface. The vehicles will cause parallel depressions (paths) of about 10-20 centimeters in depth and around ...
2
votes
1answer
96 views

Possible to use same signature file to classify images from different years?

I have Landsat images for the same area over 20 years (one photo per year in same season). I would like to detect changes occured in forested area like clear-cut and bark beetle outbreak over time. I ...