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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1answer
89 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
52 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
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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 ...
2
votes
0answers
99 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
97 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
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1answer
41 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
123 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
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0answers
28 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
56 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
110 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
143 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
54 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
48 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
174 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
49 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
77 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
176 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 ...
3
votes
0answers
63 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
31 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
364 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
39 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
34 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
351 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
57 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
67 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
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0answers
17 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
94 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
115 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
190 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
53 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
93 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
39 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
42 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
63 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 ...
3
votes
2answers
112 views

Map accuracy assessment by moving window in R

I would like to make an accuracy assessment using a confusion matrix between classified Landsat image and reference dataset. Maps have the same resolution and extent. I would like to evaluate the ...
1
vote
1answer
237 views

the difference between pattern recognition and image classification in remote sensing? [closed]

Does anyone know the difference between pattern recognition and image classification?
0
votes
0answers
17 views

How to compile the source code of module MOD14 of NASA

I'm working in a project which uses an Active Fire Detection base on MODIS (MOD14) of NASA. The source code and compiled-file can be downloaded at NASA Now I want to compile the source code, ...
5
votes
4answers
385 views

What satellite imagery would help to show spring locations?

I've got lots of tiny streams on a hydrography shapefile. Historic texts indicate that certain ones have headwaters at "sources" or springs, and I want to try to find these. Browsing the historical ...
1
vote
2answers
141 views

Lidar and infrared data to detect petroleum releases

Would this combo detect differences in soil temperature in proximity to the release due to the higher temperature of pipeline fluids or would the surface temperatures be affected by the volatilization ...
1
vote
1answer
42 views

How to extract impervious areas from Landsat data?

I'm working with multi-temporal datasets from Landsat (Landsat 8 & Landsat 7 & Landsat 5) and I tried to extract impervious areas, more exactly urban areas, but I can't obtained results very ...
0
votes
1answer
174 views

Cloud Removal from Landsat Data

I'm trying to remove clouds from Landsat 5,7 and 8 data. I'm also trying to do this using only open source options, avoiding ArcGIS. I'm familiar with python and have some QGIS experience. Originally, ...
2
votes
4answers
267 views

Determining which “color” each image band represents?

I have a satellite image that has a few bands in it. But I don't know what colors they are supposed to represent, nor do I know where to look for this information--the file's metadata say nothing ...
3
votes
1answer
68 views

“Official” definition to hyperspectral sensor

I was checking in the literature about a formal definition for hyperspectral sensors, and the most complete definition I found was from The Center of Space Research (@ University of Texas in Austin): ...
1
vote
2answers
96 views

Convert a mask image to polygon shape file using GRASS

I used image classification technique in GRASS GIS v7 and generated the image mask below in which white area has NULL value and red area contains 1. I am going to clip those red color areas in a ...
2
votes
1answer
218 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 ...
0
votes
0answers
62 views

NDVI from QGIS is giving me NaN values

NDVI,TTVI maps are nan values. when I do the NDVI calculation using the raster calculator it looks fine. what's going on?
1
vote
0answers
22 views

Determine sun elevation without header file?

I have some AWiFS and LISS-III data that I'm trying to convert from at-sensor spectral radiance to top-of-atmosphere reflectance. The problem is, the data didn't come with any header file. All I ...
2
votes
1answer
257 views

How to use the same ROI for multiple LANDSAT images in ENVI?

Suppose that I have 3 landsat images with the same datum ( WGS-84 ) and projection system ( UTM, Zone 39N ) as follows: TM LANDSAT 5 image for July 1987 ETM+ LANDSAT 7 image for July 2001 OLI_TIRS ...