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
46 views

How to detect temporal changes using ArcGIS?

I want to show urban sprawl in a city over ten year period. I took a MOOC on geospatial revolution, therein a link was shared to do such analysis. I just want to show the urban sprawl, nothing ...
1
vote
1answer
93 views

How to display the one band layer in pseudocolor using ERDAS Imagine?

I am a new user in ERDAS imagine and i found it hard to turn the single band raster data from grey color to pseudocolor using ERDAS imagine. This process could be easier to be performed using ER ...
2
votes
0answers
23 views

ASTER mineral indices with VINR and SWIR data

I need to run a supervised classification on ASTER data in order to map a rock formation, which is composed of chert. There is no shortage of indices which can be used to highlight silica rich ...
3
votes
1answer
63 views

Is the bilinear resampling technique appropriate for the projection of ASTER data?

I need to project some ASTER data from a geographic coordinate system to a projected one. I have read online that the cubic resampling technique is the most appropriate for this purpose. However, ...
2
votes
1answer
77 views

How to improve classification accuracy for 3-band (RGB) imagery?

I am hoping to extract some simple vegetation features (sagebrush) from 1m 3-band (RGB) NAIP imagery. Unfortunately, there is no near-infrared band available for this dataset and I need to use this ...
6
votes
1answer
168 views

Ditch Extraction using LIDAR DTM (1m resolution)

I'm trying to extract ditches using the LIDAR DTM using the software eCognition but I am actually having a hard time since the paper where I based my workflow entitled "Ditches’ network extraction and ...
8
votes
1answer
204 views

River boundary (bank) extraction from LiDAR

Is there any way to extract a river boundary (bank) from LiDAR data and its products (DEM, intensity image and slope) automatically? Digitizing is very time consuming.
1
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0answers
64 views

Batch GDAL_Calc multiple band calculation

I have a question concerning gdal_calc. I´m running windows 7 64b and am working from the OSGeo4W shell. I have multispectral images that need to be prepared for analysis but they are not saved in a ...
0
votes
1answer
80 views

Extract elevation data from Landsat / MODIS imagery?

Just curious, have anyone tried to extract elevation data from LANDSAT or MODIS imagery? So far, I came across one journal by Toutin who did so using adjacent LANDSAT 7 imageries. Results seem pretty ...
1
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0answers
44 views

Urban Heat Island USING ENVI

I have downloaded MODIS images for a specified area.. Its my first time that I am working on UHI (Urban Heat Island).. I need to know the methods to work on it.. I am using ENVI for this.
1
vote
1answer
48 views

Easy Guide to ESA satellite data?

Can anybody provide user friendly guidance to ESA datasets? What is available? When will new stuff be available? I struggle to work out what might be interesting amongst the many websites and their ...
3
votes
1answer
111 views

Dark Object Subtraction QGIS

I'm trying to do Dark Object Subtraction (DOS) for a Spot2 and 4. I have calculated the TOA reflectance and now want to get the at surface reflectance. Using QGIS I would like to know how I can do ...
1
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0answers
155 views

Calculating TOA reflectance from Radiance using Erdas Imagine for a Spot2 image

Using the SPOT equation ρ = π L/[E cos (θs) d-²] to calculate TOA reflectance from Radiance. L was calculated using this equation [L = (X/A) + B] d was calculated by converting date to julian day ...
0
votes
2answers
191 views

How can i convert .tif file into headerless (flat) binary files?

I am using NDVI files (value range -1 to +1) created from Landsat CDR images to produce a timeseries in TIMESAT software. My .tif file has following characteristics. File type TIFF,Data Type ...
-2
votes
1answer
118 views

Automatic Lineament Extraction from satellite images using ENVI? [closed]

Can you tell me the steps of automatic lineament extraction from satellite images? Can ENVI perform edge detection and the lineament extraction?
4
votes
1answer
56 views

Is it possible, and if so how, to effectively classify vegetation types using false near infra red imagery?

Background : I use near infra-red imagery to delineate wetlands and water bodies with good success. It's also obvious to distinguish between new healthy vegetation and older growth and land areas with ...
1
vote
0answers
26 views

How to create Strips with GCP point distribution for raw GeoEye satellite imagery?

I have raw GeoEye satellite imagery, I just want some guidelines for creating a strip map with GCP distribution. We need to make orthorectification for raw GeoEye satellite imagery, I think it's ...
3
votes
0answers
111 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). ...
1
vote
1answer
116 views

Erdas Imagine DN to TOA reflectance for SPOT images

I would like to convet DN to TOA reflectance in Erdas Imagine 2013. I see there is a way of doing this for Landsat7 in the Radiometric tab. How can I do this for SPOT2,4,5 images?
-1
votes
1answer
42 views

Most suited Remote Sensing [closed]

What will be the most suited remote sensing data to use for mapping highways in North America?
2
votes
1answer
146 views

Best Landsat band for forest classification?

Using Qgis and the Semi-Automatic Plugin for Classification, which are the best Landsat bands to use to classify trees species (in central Argentina)? In Landsat 5, 7 and 8?
1
vote
0answers
29 views

Water grey levels - remote sensing

by viewing two bands in erdas imagine the grey levels of the water differ. on the one image as below the water is dark and the other image the water is light. why is that? what cause the ...
3
votes
1answer
58 views

What's this line in Landsat MSS image?

I have a Landsat MSS image file that contains a vertical string of incorrect pixels. Does anybody know what this might be?
1
vote
1answer
131 views

SPOT 2-5 convert DN to TOA using QGIS

I'm new to QGIS and I would like to convert SPOT(2-5) images from DN to TOA. How do I go about doing this? I've an idea of how to do it for Landsat images however I'm not sure about SPOT.
2
votes
1answer
175 views

Random-Forest Classification of 10cm Imagery for species-distribution in R (no point-shapes)

I'm actually trying to classify 10cm-resolution images with the RF-package. I do this to separate some species in the forest, seen on my images. While I was searching for an answer, I found the ...
3
votes
2answers
59 views

Is SRTM 3 second arc free of non-terrain features?

I made an elevation map of my study area in Macapa, Brazil. But the region has the average elevation lesser than 30 m as I can see from my map derived from SRTM 3 second arc. According to my ...
3
votes
1answer
56 views

ICESat/GLAS coordinate system conversion

I have to import ICESat GLAS14 product data into ArcGIS. I managed to export into an ASCII file the binary GLAS data using NGAT tool, but the coordinates system are in an uncommon format ...
2
votes
3answers
209 views

Download high res NDVI imagery

I'm trying to find a good source of NDVI imagery, but I'm struggling to find proper high res imagery, particularly for northern Europe. Does anyone have references to high res imagery, that is ...
2
votes
1answer
57 views

Does EO-01 Hyperion L1GST data show DN values, radiance or reflectance?

I am working on Hyperion hyperspectral imagery and I cannot figure out whether L1GST level does do show DN values, radiance or reflectance.
4
votes
3answers
88 views

Colour matching satellite imagery from different time periods

Is it possible to colour match two separate satellite images taken at two different times? I am working with two high resolution, multispectral images that were taken approximately one year apart and ...
2
votes
1answer
201 views

Calculate EVI From Landsat 8 in QGIS [closed]

I have calculated atmospherically corrected reflectance values for Landsat 8. From that, I am getting correct values of NDVI in QGIS, but for EVI I am not getting the correct values. For some images ...
4
votes
0answers
73 views

Multispectral image segmentation for natural-resources applications using R

R has the capacity for image segmentation, although all of the examples I have come across utilize a single band for the segmentation (example). I am interested in combining R's capacity for random ...
2
votes
1answer
36 views

How to read ASTER metadata in IDL?

I'm trying to read many ASTER images (1B mainly) in IDL (I can try in R also). I'm used to work with Landsat, but the aster metadata is complicated. I write a code with a lots of conditional that can ...
3
votes
3answers
377 views

How to extract surface from air photo avoiding trees and buildings?

I am working with Drone air images. These are geotiff images and clearly portray trees and buildings. I need to first classify the image according to land cover distribution, then need to remove the ...
1
vote
0answers
24 views

Prediction of coastal change [closed]

I have vector data in coastal change for two separate years, like 1950 and 2000. I want to use GIS to create a "Prediction of coastal change" in 50 years, 2050. How do I figure out what is the shape ...
1
vote
2answers
68 views

Landsat images with more than 3 colored bands

I’m looking for a website where I can find Landsat images (or similar to it) with more than just 3 color bands. http://glovis.usgs.gov/ only gives me 3 bands. Is there a way to obtain more band? ...
1
vote
2answers
46 views

How to calculate regrowth area?

Thanks to Best Landsat-5 TM band combination for detecting fire scars I am able to calculate burnt area in an absolute way (Normalized Burn Ratio). Does a ratio or delta operation exist to calculate ...
1
vote
1answer
37 views

Determine changes in land cover of isolated features over time?

I have a a study area of 2 Landsat scenes from 2013 which were classified for a specific natural community, and these areas have been isolated and extracted and digitized into vectors so that they can ...
4
votes
2answers
376 views

Best Landsat-5 TM band combination for detecting fire scars

I am looking for the best band combination with Landsat 5 imagery to detect fire scars.
1
vote
1answer
65 views

create a vegetation mask using Landsat 7 [closed]

I'm working on a very large study area. The aim is to create a vegetation mask representing only pines. I'm using Landsat 7 images. Since the recordings were made in the winter it's pretty easy to ...
1
vote
1answer
71 views

How to interpret Lidar scan line problems?

I am calculating various gridmetrics using the Lidar processing tools in FUSION. The dataset I am working with contains 154 flight lines of high density data, at a nominal pulse spacing (NPS) of 1.5 ...
0
votes
0answers
18 views

Urban heat island

Since there are lots of products in MODIs for Urban heat Island can anyone suggest me which is the best one?and why?I need to start working on Urban heat Island of some city in Asia but before that I ...
1
vote
2answers
100 views

How to find the minimum pixel value within a region of interest?

I am working on a Python script for dark object subtraction, a radiometric correction method for remotely sensed data.To accomplish this, I need to find the minimum band pixel value of a waterbody ...
0
votes
1answer
128 views

Reproject MODIS level 3 chlorophyll data using gdal

I am trying to reproject MODIS Level 3 chlorophyll data (for instance, this file) using gdal in R. I used gdal_translate and gdalwarp functions. There was no crs information associated with ...
2
votes
1answer
209 views

Image classification using google satellite images

Currently our expert user classifies locations by viewing the Google earth satellite image of a location. They consider circular areas of a 5km radius at a set zoom level. They evaluate the image for ...
2
votes
0answers
61 views

R: Can raster predict function pass to predict.rfsrc (a prediction function in a parallel verion of RandomForest)?

It seems that raster predict function can pass to predict.randomForest by setting the "type='response'". I am using a parallel version of randomForest package called the "randomForestSRC" and I am ...
1
vote
1answer
101 views

Processing MOD35_L2 HDF Cloud Masks

I am attempting to create a binary cloud mask from the MOD35_L2 data products located at http://ladsweb.nascom.nasa.gov/data/ When opening the MOD35_L2 data in ENVI or the MRTSwath tool it reports 6 ...
1
vote
1answer
42 views

Creating training areas for parametric classifcation

I am creating a signature file for a supervised classification for a subset of a LANDSAT image. I know what classes I would like to create, and have identified ideal areas for training. However, I am ...
1
vote
1answer
49 views

.ecw versus.ers

I have two (seemingly identical) historic Aerial photos of my county of interest. One has a .ecw file extension and one has a .ers extension. I've been using the .ecw without trouble, but wanted to ...
3
votes
0answers
69 views

Thermal Map Data

I am curious about making a thermal map to display where the hot spots and where the cool spots in a community are. Obviously the roads will be hot and the shaded areas with trees will be cool but ...