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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9
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2answers
880 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. ...
4
votes
3answers
97 views

Estimating vegetation composition from digital images

I am running a Master's project researching Greater prairie-chicken nest and brood survival. Some of my intended covariates include local vegetation measures using digital imagery. I would like to use ...
5
votes
2answers
466 views

What are LiDAR returns?

Can someone help with an explanation and some references, in order to understand the nature of return pulses within a LiDAR system.
0
votes
0answers
23 views

Landsat Data to Map Slums in India

I am working on a project to answer the following geographic question: How much have slum areas increased in Mumbai, India, since the 1970's (or earliest data). I have downloaded LandSat imagery and ...
1
vote
0answers
11 views

How to classify land cover with MMU 25hac

By using the 30 meter resolution of landsat TM & ETM+ data, I want to create the land use/ land cover map. I have read in several studies to first decide about the minimum mapping unit (MMU) that ...
0
votes
1answer
192 views

Masking clouds with Fmask

I have been trying to mask clouds with the quality control band with landsat 8 imagery. The problem I continue to run into is that the quality control bands mistake tops of buildings and concrete as ...
1
vote
1answer
18 views

How to remove band from stack in ERDAS 2013?

I have a Landsat 8 scene where I have stacked 11 bands. I need to remove one band from the stacked layer. Is there a toolbox in ERDAS 2013 that allows me to take out a band? I am aware that ENVI ...
21
votes
6answers
3k views

Is GPS more accurate on specific hours of the day?

I have heard that the GPS system is more accurate, and less accurate on some specific hours on the day. If this is true, how can I get the information on when GPS is more or less accurate at my ...
0
votes
0answers
11 views

NDVI for natural region

I have a question about remote sensing, I appreciate that if somebody can answer to me. I have remote sensing data which I have got from landsat 7. The area which I am working on is combination of ...
1
vote
1answer
33 views

Python/GDAL hyperspectral Image wavelengths

I can open and read a hyperspectral image using GDAL according to the instructions brought by Max König here: So after reading the data like this : data = gdal.Open( filename ) then I can see ...
0
votes
0answers
21 views

When parametric classifiers fail?

In which situations are statistical assumptions (e.g. multivariate normal distribution within spectral classes) for parametric classifiers (e.g. maximum likelihood ) not valid for land-cover ...
3
votes
2answers
338 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 ...
1
vote
0answers
36 views

Landsat 7 band 6 VCID 1 (LOW) or VCID 2 (HIGH) for temperature map?

I want create water temperature map with Landsat 7 on QGIS. Band 6 converting to temperature, I read the landsat handbook with formula: T= K2/ (ln((K1/L)-1)). Band 6 has VCID1 "low" and VCID2 "high" - ...
1
vote
2answers
36 views

Where to download 4-band NAIP imagery for California?

I've been trying to find orthoimages with 4 bands for a couple of counties in California. I managed to download some from the GeoSpatial Data Gateway from the USDA (NRCS), but they all only have 3 ...
2
votes
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 ...
3
votes
1answer
54 views

Calculate change in canopy height over 10 years?

I want to know how many "tall" trees (greater than 30 m) fell down between 2005 and 2015. I have LIDAR imagery from 2005 and 2015 from an area where many tall trees are known to have fallen due to ...
1
vote
1answer
35 views

How to create an image of maximum pixel values from an input layer-stack image in ERDAS Imagine?

I have 12 MODIS images (one of each month). I want to create a single image having maximum annual pixel values for each pixel. I did layer stacking operation in Erdas Imagine 13, but how to extract ...
3
votes
3answers
451 views

Tasseled Cap Transformation Rapid Eye

I want to do tasseled cap transformation on rapid eye data. the main question would be about the parameters which are used. Somebody has a suggestion?
4
votes
3answers
124 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.
9
votes
5answers
6k views

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 ...
2
votes
1answer
32 views

View feature space for multi-band files

I am trying to plot a feature space (scatter plot) for some SPOT images in QGIS 2.8.1. I know a histogram is available in the file properties, but I want to plot eg. Band 1 vs Band 2 to see the ...
0
votes
2answers
60 views

AVHRR Max NDVI product

I'm trying to take a max annual NDVI product derived from AVHRR and relate it to a specific area that I'm examining.This requires me to identify the region of interest based on Landsat scenes, and ...
1
vote
1answer
31 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 ...
0
votes
1answer
29 views

True color combination using Resourcesat-1?

I am working with an image from India. According to the metadata, I am working with an image acquired by the AWiFS sensor from Resourcesat-1: ...
6
votes
1answer
175 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 ...
1
vote
2answers
53 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 ...
0
votes
1answer
150 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. ...
1
vote
2answers
163 views

Band conversion from different landsat imagery (Landsat 5,7 and 8)

I am mapping mangrove areas over time (from 2003 to 2014 ) and thus use different landsat imagery. Band combinations i use and am satisfied with in Landsat 7 include band: 4,5,3 4,5,1 7,4,2 when using ...
1
vote
1answer
21 views

MODIS MOD10A2 snow product

I have extracted pixel value ( pixel value=200 for snow) from MOD10A2 snow product for my study area. Since MOD10A2 product is distributed every 8-days. i.e., 9th Jan, 17th Jan, 25th Jan,2nd Feb,.... ...
1
vote
1answer
189 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
votes
1answer
47 views

atmospheric correction in ENVI 5.1

I want to perform atmospheric correction on Landsat 8 images in ENVI 5.1. In order to create radiance image, I selected basic tools> preprocessing> calibration utilities> Landsat calibration. However, ...
1
vote
1answer
76 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 ...
1
vote
1answer
50 views

view zenith angle and view azimuth angle with Quickbird

I am trying to do an atmospheric correction on a Quickbird scene. I am creating a user-defined geometry which requires six parameters. The six parameters are solar zenith angle, solar azimuth angle, ...
3
votes
1answer
225 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 ...
3
votes
1answer
481 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 ...
1
vote
0answers
12 views

Hyperspectral Image + Field Data

There is plenty of remote sensing datasets out there, but I haven't been able to find one along with field data. Particularly I am looking for airborne hyperspectral images that have field data ...
0
votes
1answer
38 views

Remote sensing product data catalog? [closed]

Since there are a huge number of remote sensing products available, I feel confused. Is there any data catalog for data specification, date of acquisition, and type of application?
1
vote
0answers
58 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 ...
0
votes
1answer
18 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
votes
1answer
2k 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
votes
2answers
92 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 ...
1
vote
5answers
146 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
2answers
604 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 ...
1
vote
0answers
41 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?
3
votes
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 ...
1
vote
2answers
512 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 ...
0
votes
0answers
40 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 ...
6
votes
3answers
303 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
votes
2answers
83 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
votes
2answers
196 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 ?