- Fardin Mirzapour added an answer:Where 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).
- Richard Gloaguen added an answer:Has 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.
- Sid James Nelson added an answer:Does 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
- Piotr Kowalczuk added an answer:Anyone 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?
The best strategy is to test retrieval algorithms at longer wavelengths. You should check the band rations algorithms with spectral band combination Rrs(550)/Rrs(590). We have tested it in the Baltic Sea and it works. You could also try Rrs(550)/Rrs(620) combination. Another strategy is to retrieve the total absorption at 676 nm from semi-analytical algorithms and than relate it to chlorophyll a concentration. CDOM absorption at 676 is negligible even in most organic reach waters.Following
- Lotfi Mustapha KAZI-TANI added an answer:Why 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:What 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 ;-)
- Michael Wulder added an answer:Can 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.
Great answers! Here is another option that may / may not be applicable. Prof Roy (SDSU) has a tutorial that shows how to use WELD data and tools for extracting and manipulating a time series of a given pixel.Following
- Frank Veroustraete added an answer:How can I detect desertification by remote sensing?Which image product is best suited for this purpose and how can I download that product?
I made a study of desertification in the Xinjiang province (North- Western China) lately, using a multi-temporal series of 50 years Corona and Landsat imagery. The LUCC is enormous over that time lapse in the Xinjiang province. It led to increased desertification in originally natural landscapes. In short, an originally natural landscape with gallery forests along the Tarim river and its tributaries changed into a patchy landscape with irrigated agriculture plots on the one hand and sandy deserts on the other hand. This LUCC had a fundamntal impact on regional hydrology. The Tarim river in the 50 years mentioned retracted by more than 200 km from its original Gobi desert ending. If you want to know more, then read the paper available on ResearchGate:
I think that the Xinjiang province gives a fairly good example of what large scale desertification is all about e.g., humans changing natural landscapes - in equilibrium with regional hydrology - replaced by desert and irrigated cropland (mainly cotton for export to SoutWestern China sweatshops). In fact the original water resources in the new landscape has been focussed on irrigated agriculture and the original natural landscape degraded into sandy desert. Another large scale example exists in Kazakhstan (Aral Sea), not that far Norrth from the Xinjiang province, with the difference that the Aral Sea has almost vanished into pure desert. Al fishing activities in the Aral Sea have stopped and people had to move or die.
- Regan D added an answer:How can I apply my image classification algorithm on these data in matlab environment?
I find HSI images on this link: http://www.ehu.eus/ccwintco/index.php?title=Hyperspectral_Remote_Sensing_Scenes. But all are having more than 10 no. of channels. Want to know how can I use this in matlab for image classification. Because I don't know what are the RGB channels among various channels. If it is possible convert them into tiff format? Thanks in advance
Could you explain further in detail about " construct a matrix with N by M row and 10 column (if 10 channels). Use 90 % of the row for training and test with the rest for instance with a 10-fold cross validation for instance" from your answer.
Thanks in advance.Following
- Emmanuel Bratsolis added an answer:Is there any study on the terrestrial stratopause level that compares satellite remote IR data with direct in situ recordings?
Do remote satellite recordings show discrepancies between in situ samplings for the same atmospheric level and especially the stratopause on the Earth within a narrow timeframe? Such direct sampling may occur by balloon missions or probe decent.
The temperature structure of the winter atmosphere at South Pole
Weilin Pan and Chester S. Gardner GEOPHYSICAL RESEARCH LETTERS, VOL. 29, NO. 16, 10.1029/2002GL015288, 2002
The Remote Sensing of
John P. Burrows
- Gerald J. Rys added an answer:Are you aware of the use of hyperspectral methods from aircraft to assess water quality?
I'm interested in any research that might be using hyperspectral techniques from aircraft to routinely measure water quality eg nitrate levels, in lakes, rivers and waterways.
regards Gerald Rys
Agata thanks for your useful papers cheers GeraldFollowing
- Shukla Acharjee added an answer:What are the current challenges & innovations in Geothermal Resource Exploration?
Geothermal Energy has long been regarded as Green Energy's silver bullet. And rightly so because of its potential as a stable, secure, environmentally friendly and a cheap Energy resource. But there are some obstacles.
Firstly, Not everyone lives on top of a Volcano! Unlike wind and solar installations which can be built more or less anywhere, Geothermal Power Plants can only be built on geological hotspots that exists less than 10 % of our planet. Secondly, even in hot spots like Iceland, Engineers must deal with the most daunting technical challenge facing geothermal. Drilling! That's because all successful Geothermal ventures require three vital elements. Hot Rock, Water and close proximity to the resource. Thirdly, money and potential exploration risks are additional issues to be dealt with.
Remote Sensing techniques have been aiding in identification of Geothermal Hot spots with thermal anomaly, geological and mineral mapping studies. Geophysical techniques such as resistivity, gravity, seismic and geodetic measurements are valuable in the exploration phase. Next, Geochemical sampling and analysis takes over. RS & GIS are also applicable in Environment Impact Assessments after a Geothermal Power Plant is set up. Recent developments have seen the arrival of Unmanned Aircraft Vehicles (UAVs) for geothermal exploration.
What are the challenges faced by the Geothermal Explorers in different locations such as Indonesia, Kenya, US, Philippines, Japan, Iceland, NZ, Aus., EU and elsewhere. Are there any potential hazards due to their proximity to Volcanic systems.
Requesting all subject-matter experts to enlighten with their relevant answers.
Mr. Varghese, the image was given to the contestant free of cost as a part of 8band challenge. till date i havent got any work on geothermal in this arunachal himalayan belt though it has potential areas. one more area is the mikir hills.Following
- Rajesh Dhumal added an answer:How can I start learning hyperspectral remote sensing for agricultural applications?
I would like to use hyperspectral imaging data for monitoring against Drought, Disease, and nutrient stress of crops. I found that it can be studied using EnVI software. I am looking for a beginner's document or relevant papers.
Lots of open aceess literarture is availableFollowing
- Pat S. Chavez, Jr. added an answer:What is hyperspectral imaging system and how does it function?I'm currently preparing the research related on the hyperspectral imaging system. Anyone have any idea how the hyperspectral camera works, understand the hyperspectral camera structure and construction diagram? One more question, what is the difference between using prism and grating in hyperspectral camera.
My expertise is in remote sensing and use of imaging systems that have included optical, microwave (radar), and acoustic imager of the Earth surface (including the surface of the bottom of the ocean --- shallow and deep waters). Multispectral (4 to 12spectral bands with mostly visible and near-infrared wavelengths) started to be used in the late 60s and into the 70s; hyperspectral airborne (not on satellites) started to be developed in the early 80s and more or less operational in the late 80s to early 90s (main one developed by JPL --- a NASA center), with some experimental ones on satelllites in the 90s and 2000s. These are more or less optical systems that have spectral bands in wavelengths from the lower part of the blue to the near-infrared and onto the short-wave infrared (1.5 to 2.4 range); some of the systems also carried a thermal imaging capability
Besides optical there are also radar and acoustic sonar imaging and profiling capabilities (multi and dual frequencies) to look at characteristics on the earth surface.
I've had an interest in how some of these type of imaging may be applicable in the medical imaging field. Not know the state of the art in the medical community I look forward to learning about comparable capabilities.
- Max Fernandez-Alonso added an answer:Is there literature about methods to detect active fault by using hyperspectral remote sensing?
Are there books & papers dealing with methods to detect active fault by using hyperspectral remote sensing. Or does anyone have good idea?
Hyperspectral RS to identify active faults is not the most convenient method, unless the fault trace influences the overlying / covering vegetation and / or soil composition (e.g. higher water content that should be detectable, different mineral composition - mylonites). Even then, one still has to ask if this due to recent fault activity or just because of the presence of a (paleo)fault.
Other methods in optical and NIR RS are based on identifying active faults on geomorphological criteria.
Much better however is to use SAR radar interferometry (inSAR).Following
- Ram kumar Singh added an answer:How do I find out water depth from Level 1Gst Hyperion hyperspectral data?
I have tried to find relative water depth and absolute water depth of a river channel in coordination with ground truth data by using ENVI SPEAR tool.I have taken the inbuilt envi log ratio transform bathymetry method. But it is showing error like IDL_IGAMMA failed to converge. Please anyone suggest, how to do this step by step to know water depth of river channel using ENVI?
Kindly check the projection of hyperion and gcp point into meter system.
-Ram Kumar SinghFollowing
- Lukas Fraser added an answer:How do you use FODIS data to convert from radiance to reflectance?
I have images from a Specim SWIR terrestrial hyperspectral camera, and I have converted them to radiance. I also have FODIS data, which can be used to convert to reflectance, I'm just not quite sure how to do this.
image: n lines, 291 samples, 256 bands.
FODIS data: n lines, 1 sample, 256 bands.
Any suggestions would be greatly appreciated.
Thank you all for your responses, they were quite helpful!Following
- Sabelo Madonsela added an answer:Should I re-sample before or after classification to use satellite images at different resolution?
I have satellite imagery of different resolution, the same area different epochs. I wish to carry out a change detection after land use land cover. Should I re-sample before or after classification? any articles discussing the pros and cons of either approach ?
In case you want to resample to fine resolution, consider pansharpening with panchromatic band.Following
- William Miller added an answer:What hyperspectral imagers are available on satellites?
Would hyperspectral sensors be able to detect and map coastal bottom features?
As of last week, the HICO sensor on the International Space Station was declared dead with no plans to repair/replace that I know of. So the data is still good but we will be getting no more.Following
- Sidik Mulyono added an answer:Where can we find an annotated MODIS or LANDSAT open dataset for classification benchmarking?
We developed several machine learning techniques for growth stages classification based on MODIS (or later incorporating LANDSAT). Currently, we obtained results on our own annotated dataset based on field survey. Are there some open annotated dataset that we can compare our algorithms to this data?
Thank you for your kindly reply. Actually, we have been developed generic model for paddy growth stages detection using remote sensing data. Firstly, we built the model using low spatial resolution (MODIS 250m), and now we extend our model by using higher resolution RS (such as Landsat, SPOT, etc). What we are going to do now is to validate our model using annotated RS data that labeling each growth stage of paddy crop, i.e. vegetative stage, reproductive stage, ripening stage, harvesting stage, and plowing stage.Following
- Hasmukh J Chauhan added an answer:What are the best preprocessing steps for Hyperion hyperspectral data sets (Level 1Gst, Level 1T)?
I have downloaded level 1Gst and level 1T hyperion hyperspectral data for my study area, in order to use in mineral mapping, however, every time I try use FLAASH for atmospheric correction it gives an errors or bad results. Should I use the toolkit then subset (removeing bad bands) then FLAASH or not? Also should I put specific advanced paramters in FLAASH?
How I use FLAASH atmospheric correction using ENVI (what ideal parameters for such data sets)?
In addition to atmospheric correction destripping required to apply to remove stripes. After that MNF needs to be applied to separate signal and noise component.Following
- Mohan Bahadur Chand added an answer:How can we calculate thermal resistance from Landsat Image?
I want to estimate thermal resistance of the debris-cover glacier using the Landsat Image, since it is free. Does any body can answer this question?
Yea Hayder, I am also searching for the same and I need algorithms for in GIS or ENVI paltformFollowing
- Shian-Loong Bernard Lew added an answer:Can anyone recommend a geoinformatic methodology, utilizing remotely-sensed images, to assist in isolating tourism-induced development?
Preliminary checks turned up the following:
- Night light emissions & Light per capita
- Smog/Smoke emissions
- Hyperspectral imaging
So far there is one study I am aware of that is along the lines of the question:
Dear Bin Jiang,
Thanks for the links and the suggestions to the sources of data.
Dear Hein Van Gils,
Very helpful advice on the application context- yes settlements much like cities involve probably the same dynamics as cities, albeit at a smaller scale. Also the non-urban nature of some of nature-based tourism may allow the advancement of the methodological toolkit beyond urban tourism
- Khatir Benhanifia added an answer:Are the Landsat 8 OLI data available without terrain correction and with view geometrical configuration? Are Spectral Response Functions available?
The Landsat 8 OLI images with terrain correction are not useful for atmospheric correction aims. I would need the radiance image acquires by sensor without processing; the geometrical parameters of the acquisition (view zenith and azimuth angles); the spectral response function of the OLI channels. Can I get them somewhere? Can someone help me? Thanks
I think Landsat OLI images are not terrain corrected (using slope and aspect to delineate spectral effect of terrain morphology) but terrain orthorectified (georefenced) using GCPs or DEMs. The product is delivered in 16-bit unsigned integer format and can be rescaled to the Top Of Atmosphere (TOA) reflectance and/or radiance using radiometric rescaling coefficients provided in the product metadata file (MTL file).
- Akim Mahmud added an answer:Remote Sensing of Marine DebrisMarine debris seems to collect in ocean convergence zones, such as the North Pacific Subtropical Convergence Zone. Assuming that one can map these convergence zones using satellite remote sensing, what would be a cost-effective way to check whether they contain marine debris? Can high concentrations of plastic waste in the ocean be detected remotely?
please let me know , if there any recent research on this matterFollowing
- Gabriel Hmimina added an answer:Field Spectrophotometer for Vegetation ReflectanceWe are going to collect more than 300 sample plots in 19 districts for the biomass and carbon stocks study. I am thinking why we should not include "Field Spectrophotometer for Vegetation Reflectance". If you have experience, please share with me;
1: Advantages and Disadvantages
2: Different models of Field Portable Spectrophotometers with prices
The saturation issue may not be caused by the spectrometer. There may be too much incoming light. If you are using a diffuser or lense directly mounted on the spectrometer, you should try using an optical fiber to limit the amount of light which pass through the spectro slit.
If you are already using a fiber, you should try another one with smaller core diameter.
Most of the time, one should avoid working with small integration times since it is much more sensible to changes in incoming light, thus hard to get a stable measurement.Following
- Saif Uddin added an answer:Which is the best possible algorithm and satellite dataset for estimation of suspended particulate?Which will be the most suitable satellite data to estimate suspended particulate matter in shallow turbid areas like the Northern Persian Gulf?
Chavez you are right. But didi you experiment with MODIS data? I see band ratios work quite reliably in areas where the SPM is around 10 - 30 mg/LFollowing
About Hyperspectral Remote Sensing
All remote sensing topics related to hyperspectral data.