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Questions tagged [remote-sensing]

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.

http://support.esri.com/en/knowledgebase/GISDictionary/term/remote%20sensing

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Difference between Albedo and Surface Reflectance

Can anyone tell me what is the difference between Albedo and surface reflectance? I know for sure that they are not the same. Any links / comments are most welcome.
GBh
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Difference Between Radiometric calibration and radiometric correction

I am new in remote sensing field. I sometimes got confused when I read about image pre-processing. Can someone please elaborate to me the difference and some example methods to do radiometric correction and radiometric calibration ? Is converting…
Ilyas Nursyamsi
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NDVI in urban environment

What considerations should be taken into account when trying to derive a NDVI from an urban environment? I pulled a tree canopy layer from LAR-IAC data and used an NDVI of 0.38. However, this FAQ on Vegetation in Remote Sensing recommends using…
htomita
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Resources for Calculating the Geometry In Oblique Photographs

Currently I am using supervisory classification algorithms to calculate the landuse within a certain image, the issue being the images are sourced from high oblique photography. I know the focal length and dimensions of the camera used, and the GPS…
Mark Iliffe
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Detect cattle on high resolution satellite images

I have no deep experience in remote sensing. I would like to know if it might be feasible to detect cattle (i.e. a single cow or bull) from a high resolution satellite image e.g. Worldview 3 with a spatial resolution of 0.31m. I was thinking about…
user2383726
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What should come first-Radiometric calibration or co-registration?

For a pair of images,in the pre-processing of satellite images, which step should come first- Radiometric calibration or co-registration?
Nancy
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Is a photo of an infrared slide taken in a light box a digital Infrared image?

Many years ago we received many aerial infrared images. They were developed on transparent film like a slide but much bigger - 20cm x 35cm. If I now take a digital photo of these images, are they real digital infrared images? I am trying to…
Robert Buckley
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Should Endmembers be Normalized for Linear Unmixing?

In biological spectral microscopy, the standard in the field is to use normalized endmembers in linear unmixing algorithms. In most cases, the endmembers are normalized to the maximum value. I have not found a reference that explains why…
user54174
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Image sizes for VHR remote sensing image

I need to compare three or four different segmentation algorithms on very high spatial resolution remote sensing images, with a range between [0.31,1.00] meters/pixel. What image size could you recommend to me? Maybe 100x100, 500x500, 1000x1000 or…
Jaime Lopez
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A problem about Correlated-K algorithm of MODTRAN 5

When I use MODTRAN 5.2.2 to run the test case 'CorrelatedK.tp5', I get the following warning information. How I can solve this issue? WARNING: The Correlated-k option was turned off. The Correlated-k distributions file DATA/CORK01.BIN …
JZH
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Can radiometers measure radiations in the infra-red at night?

I started reading about passive sensors and radiometers in particular. I know that microwave radiometers work day and night and in cloudy conditions. Thermal radiometers can measure energy during the night also, which makes sense since the heat is…
Hakim
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Remote sensing: How to start with interferometry?

I need to start learning about the interferometry techniques available/used for remote sensing data (radar or optical). Which are the main applications? Which techniques are applied? Which Earth Observation data is more adequate? Which software…
vascobnunes
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Queries about Optical Remote sensing images

I am new in Remote sensing and studying about Optical Remote sensing images. I found a research article, "Learning Rotation-Invariant Convolutional Neural Networks for Object Detection in VHR Optical Remote Sensing Images", that is recognizing the…
Aadnan Farooq A
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Hyperspectral Imaging - Material spectral signature

I am reading about the working principles and applications of hyperspectral imaging (HSI). In this link, the uses of HSI over the range of the wavelength, from visible to longwave infrared have been summarized by the picture below. My question is,…
RuiQi
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Format of SAR images

What is the format in which SAR images are stored? By format I mean when a SAR captures an image, it gets saved in what format? jpg? png? tiff? or there is some other special format? Is there a single format, or are there multiple formats? I also…
Nancy
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