A series of Earth-observing satellite missions jointly managed by NASA and the U.S. Geological Survey.

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17
votes
6answers
790 views

What are people using LANDSAT data for?

Obviously it's potentially a very powerful tool, but I'm curious as to what practical applications people are using it for? Admittedly, this is a very broad question... The reason I ask is because ...
16
votes
3answers
5k views

Which remote sensing satellite is best used for vegetation extent mapping

I'm currently writing an assignment for my remote sensing class and while I think I have correct answer was wondering what people who do this stuff for a living think. The question is: which ...
14
votes
9answers
951 views

What is the best/easiest way to obtain temporal Landsat imagery?

It's been awhile since I've dealt with optical imagery. I need to perform a land cover classification at mid-latitudes using several LANDSAT scenes. I've noticed that some online tools are still ...
10
votes
1answer
949 views

How to compare aerial and satellite images for land use analysis?

I am interested to compare the land use-cover dynamics for four periods: 1950s, 1980s, 1990s and current for a certain area having a max size of 5000 ha. For the first three periods detailed aerial ...
10
votes
1answer
1k views

How to Remove Dark Bands Where Scenes Overlap in Mosaic Landsat TM5 Image?

I have an image mosaic of 5 Landsat TM5 scenes. Where the scenes overlap there is a dark band, only on the left and right sides, but the top and bottom are seamless. What is the best way to correct ...
9
votes
2answers
599 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, ...
9
votes
1answer
5k views

How to fill gaps in SLC-Off Landsat 7 ETM+ Images with QGIS?

Explanation of the problem: On 31 May 2003 the Landsat 7 Enhanced Thematic Mapper (ETM+) sensor had a failure of the Scan Line Corrector (SLC). Since that time all Landsat ETM+ images have had ...
9
votes
1answer
1k views

How to pan-sharpen Landsat images for image-classification in GRASS?

I'd like to learn how to do an unsupervised classification of a Landsat scene using i.cluster > i.maxlik in GRASS using pan-sharpened 15m-resolution images (the example given in its Wiki uses the ...
8
votes
2answers
1k views

Extracting roads out of Landsat raster images

For a study into the expansion of road networks in the rainforest I am trying to extract roads out of Landsat images. We already have sharp and cloud-free composites on which the roads are clearly ...
8
votes
1answer
208 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 ...
8
votes
1answer
3k 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 ...
7
votes
3answers
790 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: ...
6
votes
6answers
1k views

Southern hemisphere projections for Landsat upsets GRASS

Hi All does anyone have the last word on why Landsat scenes don't project in the southern hemisphere. This causes no end of trouble in GRASS, less so in QGIS. What I mean is, take an original scene ...
6
votes
2answers
7k views

Landsat in ArcGIS

I need to learn how to download, import and compose Landsat 8 in ArcGIS for natural colors (preferably in a GEOTIFF format). I have tried on my own but it seems that I am doing something wrong... can ...
6
votes
1answer
139 views

Difference between Landsat 7 and Landsat 8 TOA reflectance computation

In section 3.1 of this article it is explained how the Top of Atmosphere Reflectance for Landsat 7 and Landsat 8 are computed. The equation for Landsat 8 is not mentioned explicitly, but can be found ...
6
votes
1answer
612 views

How to increase mask buffer and then offset it using r.mapcalc in GRASS?

I'm in the process of learning on how to remove clouds and cloud-shadows from Landsat images using GRASS. So far I was able to remove a lot of clouds from those images using i.landsat.acca, but it ...
5
votes
2answers
3k views

Moisture Interpretation from Landsat Images

I am working on a "land suitability for crop" project. Can anyone let me know how to get any type of information which can be related to moisture index of soil? I have Landsat 5 data with band 3 and ...
5
votes
2answers
2k 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 ...
5
votes
5answers
2k views

Which methods are most suited to classifying urban areas from Landsat imagery?

I am trying to use Landsat data to map urban extents over time. I need to perform a classification into built up / non built up areas. I am new to image classification. I have access to the following ...
5
votes
2answers
2k 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 Landsat-...
5
votes
2answers
2k views

How to color-balance false-composites of pan-sharpened Landsat images in GRASS?

Whenever I try to pan-sharpen composites of some Landsat images in GRASS using i.pansharpen, i.fusion.brovey or the IHS sharpening method, the output will have some or all of the following ...
5
votes
1answer
2k 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 ...
5
votes
6answers
3k views

How to pansharpen LANDSAT 8 in GRASS?

Having used QGIS for quite some time for mapping, I was 'forced' to dig into GRASS as pansharpening is not directly executable in QGIS. After understanding more or less the structure, I did some ...
5
votes
4answers
3k views

How can I Destripe Landsat Images?

I am working with Landsat 7 ETM+ SRC-off imagery. I'm doing some land-cover classification for a place in Kenya. My problem is the no-data stripes in the image. Is there a way in which I can ...
5
votes
3answers
220 views

Differentiating bare soil and urban areas in Landsat 4-5 land cover classification?

I am trying to classify a Landsat 4-5 image using the semi automatic classification plugin (QGIS). I always get misclassifications between bare soil and urban areas as they have similar spectral ...
5
votes
3answers
753 views

Polygonize vegetation area from Landsat7 RGB using QGis / Bilko?

I'm trying to extract the areas with vegetation as a polygon-shape from a landsat7-image, 30m resolution, RGB, using QGis 1.8 or Bilko or (hopefully in the near future) ArcGIS. The area is in Northern ...
5
votes
0answers
660 views

RGB satellite image in Python with Basemap

Can anyone recommend a workflow or python library that will let me work with RGB images and BaseMap (or something equivalent - could be CartoPy). I have Landsat 8 images, and can load one in python ...
4
votes
2answers
2k views

How to trim Landsat 5 scene edges

I have a bunch of Landsat 5 scenes that I want to mosaic together. However Landsat 5 scenes have a zigzag pattern on the left and right edges as well as some bad data values along these edges. Is ...
4
votes
2answers
174 views

Random Forest to estimate land use in past with Landsat

I am new in Machine Learning and in R. I am working in my Master thesis. I am trying to estimate the LULC of the years 1984, 1990, 2000, 2011, 2014 for characterizing the forest dynamics. I have for ...
4
votes
2answers
929 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.
4
votes
3answers
750 views

Is there a FTP to get Landsat images?

I need to automatically fetch Landsat images and for that it would be handy to access a ftp with images available. Does such ftp exist? Can I access it? Ultimately I want to get cloudless images.
4
votes
2answers
750 views

cloud shadow detection

I am trying to detect cloud shadows in Landsat images. I came up with producing good shadows and cloud masks. Now I'd like to implement my cloud mask adding cloud shadows. Do You have a good idea to ...
4
votes
1answer
103 views

What proportion of the 240m area sensed by MODIS must be forest before it is defined as forest?

MOD12 is a MODIS product at 240m resolution. Landsat produces 30m resolution products, which I resampled to 240m resulting in a raster of proportion forest cover in each 240m pixel (based on the mean ...
4
votes
1answer
759 views

Estimating Landsat 7 azimuth (heading)

I am trying to understand if the Landsat 7 satellite ETM+ orbit has any significant azimuth or if it could be assumed as 0° (as it is not a pointable sensor). I searched in the web but could not find ...
4
votes
1answer
91 views

Pan sharpening of SPOT and Landsat images

Is there a way I can pansharpen SPOT and Landsat images? I have Panchromatic bands from QuickBird and WordlView-2 images and would want to pansharpen Landsat and SPOT, while still retaining features ...
4
votes
1answer
248 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 ...
4
votes
1answer
1k views

Using GDAL in python to stack Landsat bands

I am processing a large amount of landsat data. Landsat scenes ship as a collection of tiffs- one file for each spectral band, plus a bunch of masks. I need to stack some of the bands into a single ...
4
votes
1answer
489 views

Atmospheric Calibration for Landsat 7 ETM+ Gap Filling

This is for thesis work involving mapping of above-ground mangrove forest biomass using Landsat 7 ETM+ imagery. I am assessing correlations between biomass with vegetative indices, e.g. NDVI, and ...
4
votes
1answer
118 views

Determining the best month for discriminating between different vegetation types?

I ordered and downloaded several (Surface Reflectance) Landsat 5-8 images from USGS Earth Explorer with the purpose of choosing a few of them to calculate some Vegetation Indices for each (NDVI, SAVI, ...
4
votes
0answers
39 views

Ice type differentiation using satellite data

I would like to classify glacial area by categories of snow (if there is) and ice, but what's most important: between old ice and fresh ice. They have different properties that are possible to ...
4
votes
1answer
63 views

Misalignment of a lot of landsat images

I am new to Landsat images processing, and I'm trying to create land cover change maps over an area covering around 15 landsat scenes. I downloaded all scenes available, unfortunately some layers don'...
4
votes
1answer
47 views

What is the “t” in i.landsat.toar

I'm using GrassGis 7.0.0 for Landsat imagery. In the description of i.Landsat.toar under dos3 and dos4 is: TAUz = exp[-t/sin(e)] What is "t"? I cannot find any description about what it is. Can ...
4
votes
1answer
152 views

Low top of canopy surface reflectance values

I have calculated at sensor reflectance for a multispectral image and performed atmospheric correction. The reflectance values for the visible and NIR bands are between 0.2 to 0.01 for surfaces, ...
3
votes
1answer
196 views

Estimate forest stand height from Landsat imagery?

Is it possible to estimate the height of forest stands using optical (preferably Landsat) imagery? I came across this article while researching this, but it's over 20 years old and there doesn't ...
3
votes
5answers
3k views

Fix Landsat 7 SLC-off in ENVI?

I have a couple of Landsat 7 images and they all have striping as a result of the SLC failure. Does anyone have any suggestions as to how to destripe the image using ENVI? I plan to use these images ...
3
votes
2answers
380 views

Classify forest with NDVI from Landsat 8 and 7

I'd like to calculate the NDVI for multi-date satellite images of Landsat (7,8) to perform a change detection on the deforestation of the Amazon rainforest. I already acquired surface reflectance ...
3
votes
2answers
937 views

Cloud/Shadow Masking: How to shift a cloud mask in Erdas/ArcMap/Py Script

I have the task to mask out cloud cover in approximately 20 landsat 8 scenes. Creating the cloud mask for the "white part" is easy, but I need help in addressing the clouds shadow. General ...
3
votes
2answers
693 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 ...
3
votes
1answer
384 views

Is atmospheric correction necessary when working with multi-spectral indexes?

When you are working with Landsat Level 1 data and calculate indexes, e.g. NDVI, NDBI, SAVI ..., do you calculate them using raw data (pixel DN value), or atmospherically corrected data (surface ...
3
votes
1answer
1k 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 ...