- Mariusz Szymanowski added an answer:4How can I compute atmospheric function in single channel algorithm?
I am applying single channel algorithm for land surface temperature retrieval from landsat thermal infrared data.In SC algorithm,I have to compute atm function.
Here,AF is obtained from second order polynomial fits versus atm water vapor content.Could you please explain to me how I can obtain this coefficient.
please take a look at this:
p.10-11 (eq. 5a-c)
- Hans Lohninger added an answer:6Does anyone have a hyperspectral data set?
We would like to prepare some examples of spectral signature of trees. It's for my geomatic course. Thanks in advance.
here's a small collection of various hyperspectral data:
The datasets are in ImageLab format but can be converted to other formats by using the free evaluation copy of ImageLab.
- Ramesh Adep added an answer:5What does Negative values in Remote sensing reflectance mean??
After the geometric correction, i am obtaining negative values in remote sensing reflectance (Rrs). Can someone explain the reason for it? Is there any scientific significance for negative values in Rrs?
Srinivas, you just check with elevation parameter in the atmospheric correction model. Try by the average height of the features in the whole image.Following
- Eric Ariel L. Salas added an answer:3How can I use LANDSAt surface reflectance products efficiently? Can any body please explain ?
Landsat products from TM or ETM+ i have been using for LULC change detection . but now a new surface reflectance product is available . Can any body suggest is best use ..???
I agree with James and Sanjoy. I addition, you may want to check this Q&A about surface reflectance products.Following
- Felix Seidel added an answer:5Is it possible to have a combination of a hyperspectral system and lidar on the same aircraft?
This study is related to atmospheric changes in aerial imagery.Following
- Harilal Menon added an answer:4Does anyone know any open/commercial software available for atmospheric correction for HICO data using Tafkaa_6s?
The data i am using is HICO sensor hyperspectral data with scenes mostly covering the coastal area. For these kind of scenes, instead of using FLAASH(based on MODTRAN4 transfer code) in ENVI, the suitable atmospheric correction is Tafkaa_6s as mentioned in HICO website. I would like to use the Tafkaa_6s but couldnt find right software platform. should i code the algorithm or are there any softwares available for the atmospheric correction? i would like to have suggestions on this.
To carry out atmospheric correction, you need to estimate raylegih radiance and aerosol radiance. Estimation of rayleigh radiance is straight forwrad. However, aerosol radiance is not. Hence depending on the area of study (if your area of study is highly turbid water column, then you can't use NIR bands for aerosol correction as a part of atm correction. Becs even you can expect water leaving radinace in these bands. Under such circumstance, you need to derive AOD using sunphotometer and estimate aerosol radiance with many assumption like aerosol is spherical ....etc. you can decide whether to use NIR received values for aerosol correction as a part of atm correction or go ahead with generating AOD and subseuest computation of aerosol radiance.
- Xiuliang Jin added an answer:4What are the recent research trends in utilization of spectroradiometer and hyperspectral data to determine soil nutrients in black soil/vertisols?
*Am also looking for the methodology to predict spatial variability of soil nutrients (specially for pigeon pea fields in India )
* Even want to know ,predicting spatial variability of micro nutrients( other than N,P,K) may help in knowing the soil fertility index in robust manner.
You can see this weblink:http://www.sciencedirect.com/science/article/pii/S016819231530023X. Remote estimation of soil organic matter content in the Sanjiang Plain, Northest China: The optimal band algorithm versus the GRA-ANN model. This is my study.Following
- Selvaraj Ayyakkanu added an answer:7Can anyone provide hyperspectral data with ground truth information ?
My study is to develop a new algorithm for hyperspectral data classification. Currently i am using freely available AVIRIS cuprite data set and Virtual Verification method for classification accuracy assessment. Can anyone provide other standard hyperspectral data with ground truth information to test my algorithm.
Dear Ra mesh,
you can make use of E0-1 Hyperion data which available at free of cost. you can downloaded from earth explorer website.and better you incorporate envi5.1 or envi 4.8 or envi 4.7, using that software first preprocessing the data based on objective classify the data after following operation principle to hyper spectral data using ENVI software.Following
- Reza Hassanzadeh added an answer:5How to use morphological filter (opening and closing) (3*3 to 125*125) to extract the individual buildings from Quickbird images in ENVI?I am going to use morphological filter (opening and closing) (3*3 to 125*125) to extract the individual buildings from Quickbird images in ENVI? Can anybody tell me" How to do this analysis in ENVI"?
Thank you Mohsen.Following
- Mohsen Ghanea added an answer:1How can I generate the Ground truth classes for the Pavia University scene in matlab ?
I have Pavia dataset which is available as .mat file (Available @ web http://www.ehu.eus/ccwintco/index.php?title=Hyperspectral_Remote_Sensing_Scenes).
Here i want to know how to generate the classes such as tree, soil etc.
The best way is manual generation with prior knowledge about your case study. For example, I generated building layer in one of my recent studies. This is valuable for evaluation your final results. To give more information about this, you can refer to my article: " Automatic building extraction in dense urban areas through GeoEye multispectral imagery".Following
- Mohand Bersi added an answer:7Can anyone post index development method by using Hyperspectral remote sensing data?
how can i select spectral band from hyperspectral data. refer me good methodology for index development.
when working with hyperspectral data, and you fix the object of interest you can use different methods:
-use the spectral library to extract objects for example (clay minerals...)
-investigate on the pics in the spectrum, and one defining the max pics and the min pics u can use the band math to develop ur index by dividing and multiplying bands (take care of brakets it is very important).Following
- Hafsat saleh Dutsenwai added an answer:5How can I get free hyperspectral data apart from Usgs EO-1 Hyperion?
I could not get the data scenes for my study area when i searched usgs glovis EO-1 hyperion, please help with another free data source. Thanks
Thanks James and khan your suggestions were quite helpful.Following
- A. Barberopoulou added an answer:4Any experience in focusing ALOS Level 1.0 data using Sarscape 5.1 ?
I am currently trying to focus ALOS Level 1.0 data using Sarscape 5.1 in order to do SBAS-InSAR work.
I have no experience in doing so. I am not happy with the result I obtain, please see an example of result here (over urban area)
The settings I use:
Data type: ALOS PALSAR Single Pol
Global and Other Parameters are set to default
Can you confirm the result I obtain are not what I am suppose to obtain ?
How can I improve the focusing ?
I will look it up briefly when i go home. I did do this process before. Can you please confirm that you are using orbits? I have previously used orbital data for older satellite data like ERS and ENVISATFollowing
- Manish kumar Patel added an answer:5What is hyperspectral CASI imager and what is its specification ?
Concerning hyperspectral remote sensing. What is hyperspectral CASI imager and what is its specification ?
Thanks a lot @Marcos J. Montes and @ Murali Krishna Gurram for your very helpful sharing of knowledge.Following
- Theresa Mannschatz added an answer:20Has somebody tried to detect pesticides with hyper spectral remote sensing in the field?
I would like to test if we can detect and map pesticides using the "new" hyper spectral remote sensing satellites that will become available soon.
I know that spectroscopic methods can be used to analysis pesticides, but does this also work in the field? It would be a great success if it would be working to detect at least levels of pesticides e.g. applied in agriculture for risk analysis.
obrigada! Thanks! I didn't know that article. I found it on our platform (https://www.researchgate.net/publication/271557244_A_Review_of_sensor_technology_for_in-field_phosphate_monitoring). It is summarizing sensors for phosphate detection on the ground using sensors.
The conclusion for spectral sensors was that you would need a field/site specific calibration, what I agree. If you do not do a field specific calibration than uncertainties become large. The question however remains how we could bring the field measurement (which is already prone to uncertainties) to the satellite or airplane level. For many applications it would probably enough to get the general level of pollution without having extensive expensive and time-consuming field measurements. Once there is the indication for pollution then of course measures on the field scale should be implemented.
até mais TheresaFollowing
- Kamaruzaman Jusoff added an answer:7Mangrove Mapping?Can mangrove cover (extent) and main species composition be mapped with multispectral scanners or must one use hyperspectral techniques? What spatial resolution would be required for global mangrove mapping using satellites?
Try reading some of my papers involving mangrove species identification & mapping in Malaysia using airborne hyperspectral imagingFollowing
- Athiraja Atheeswaran added an answer:3How can I select the best bands from the Pavia dataset for the extraction of the different features?
Here I am using Matlab 2013A as a tool Link is given below from where dataset has been downloaded (http://www.ehu.eus/ccwintco/index.php?title=Hyperspectral_Remote_Sensing_Scenes). I have .mat file which i open in Matlab 2013A.
1. Here i want to know that which neural technique is use for the extraction of the features in the dataset.
Please refer the following linkFollowing
- Julian Rosser added an answer:4How can I validate my research outcomes with any other classifier?
Doing research in HSI classification on SVM based classifier. I'm using standard data sets for classification. I want to validate the outcomes with other classifier. It's enough to compare with the existing works or need any specific? I'm confused in it. Advanced thanks for valuable comments.
Could you compare the different classifiers using an ROC curve for each? For a binary (two class) problem the ROC curve tests how effective the classifier is at discriminating between different labels.
This would require that the SVM implementation employed is configured to output membership probabilities (rather than just the label). Other classifiers like random forest or naive bayes will generate membership probabilities.Following
- André Große-Stoltenberg added an answer:3Does anyone have knowledge on full waveform lidar and hyperspectral imagery?
Can anyone suggest to me on technical aspect of how to extract forest biomass from full waveform lidar and hyperspectral imagery (in fusion). Should I run modelling? or software processing by validating with ground data? software? algorithm? I need a general idea
Hi, there are videos and tutorials on the Lastools homepage (http://rapidlasso.com/category/videos/) that will give you a general idea of LiDAR processing and retrieving forest metrics. Lastools is also able to process full waveform data.
There also videos and tutorials on the NEON website (http://www.neoninc.org/learn-experience/work-with-data).
If you search for "lidar hyperspectral forest" you will find a decent amount of recent scientific publications.
Hope that helps!Following
- Christian Rogaß added an answer:4Can you give few alternative sources for downloading hyperspectral remote sensing data in addition to hyperion sensor?
Can you give few alternative sources for downloading Hyperspectral remote sensing data in addition to Hyperion sensor ?
You can also use simulated EnMAP data that is available from www.enmap.org and originated from hyperspectral airborne campaigns.
- Dr. Asutosh Kar added an answer:2Any advice on hyperspectral target detection ?
i am working on anomaly detection in hyperspectral imagery, but i dont have HYDICE data that most of the experiments have been done on it .the HYDICE data is used in many article as an example " A Comparative Study of Linear and Nonlinear Anomaly Detectors for Hyperspectral Imagery" M.Nasrabadi
if anyone have that data please send me the link of that,?
I have attached few papers for you. I think you will get a detailed answer of your concern once you go through it. Please feel free to ask more if you come across any doubts while reading these papers.Following
- Mahboobeh Parsapoor added an answer:3Any advice on feature extraction through the neural network form a pavia centre dataset ?
I had downloaded a Pavia centre data file (.mat format) from Here i want to know how to extract features (water, tree) from the given dataset through neural network..Following
- Behrouz Ebrahimi added an answer:10Can we draw the spectral curve for a single pixel from a satellite image (for each band)?
Considering that satellites (for example LANDSAT) take a image in multi bands and every bands take a image in spectral range (for example for band 1 of ETM+ sensor it is equal to 0.52-0.45 micrometer) so we should be able to draw the spectral curve for each pixel.
thank you so much for your answersFollowing
- Fardin Mirzapour added an answer:4Where can I find an HSI Database for research with more than 25 images?
Does anyone know where can I find a HSI database for any object or material, but with more than 25 spectral images (i.e. 25 *x*y*lambda)?
It would be nice, if somebody could propose a HSI database for agricultural, medical, food, and circuits. Thanks!
Feel free to share your database with me, I have no problem to cite your database.
Thanks in advance.
You may find a few HS data set along with ground truth map here:
These data sets have been saved in Matlab format (.mat file).
- Sid James Nelson added an answer:6Does anyone have information about the PROSPECT, SAIL and PROSAIL Models?
I want to estimate Nitrogen and other fertilizers content on Cocoa tree by hyperspectral RS. How can these models help me and can you suggest a more suitable model?
Thank you so much in advance.
The above answers should have useful information in helping select the bands of you remote sensing spectral data.Following
- Mohsen Ghanea added an answer:5Anyone familiar with mapping chl-a in CDOM rich waters?
Some river plumes have extremely high CDOM concentrations.
Are there practical correction techniques for improving the chl-a S/N in CDOM rich waters so that the chl-a concentration could be estimated?
You can refer to the following publication:Following
- Lotfi Mustapha KAZI-TANI added an answer:11Why do Vertisols show high values in redness index image?
I applied redness index to Landsat ETM+ in my study region located in the North western part of Algeria. I’ve got quite good results concerning Mediterranean red soil but I couldn’t understand why the vertisols are as bright as or even brighter than red soil in the redness index image.
The redness index is calculated as follow:
B1 : Reflectance of band 1 corresponding to the blue
B2 : Reflectance band 2 corresponding to green
B3 : Reflectance band 3 corresponding to red
of Landsat ETM+Following
- Francesco Bianconi added an answer:3What are the main criteria to select frequency scales and orientations in 2-D gabor filtering for images?
I want to extract texture features from images using 2-d gabor filtering. What are the way to choose frequency range and how many scale i should use.
Here's a paper you might find useful:
Bianconi, F., Fernández, A. Evaluation of the effects of Gabor filter parameters on texture classification (2007) Pattern Recognition, 40 (12), pp. 3325-3335.
Apologies for citing my own work ;-)
About Hyperspectral Remote Sensing
All remote sensing topics related to hyperspectral data.