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  3. Hello sir, I am Priyanka Kumari PhD scholar working on CRISM data set using machine learning. I wanted CRISM labelled data set to train the neural network model, how can I get labelled CRISM data set?
  4. Last week
  5. November 25th, 2020 Release 15 of MRO CRISM MTRDR (Map-projected Targeted Reduced Data Record), TER (Targeted Empirical Record), and TRDR (Targeted Reduced Data Record) browse and extras data has been loaded into ODE. This release fills in data from August 9 through November 8, 2008. See https://ode.rsl.wustl.edu/odeholdings/Mars_holdings.html for more information.
  6. November 24th, 2020 - New MEX VMC Data Loaded into ODE - Loaded MEX new VMC EDR & RDR data products released with coverage through June 30th, 2020 (Orbit 20854). See https://ode.rsl.wustl.edu/odeholdings/Mars_holdings.html
  7. The attached paper will show you how the library was created. Ray Arvidson Viviano-Beck_et_al-2014-Journal_of_Geophysical_Research__Planets.pdf
  8. Hi, Take a look to these pdfs (more precisely to the last one): https://pds-geosciences.wustl.edu/workshops/CRISM_Workshop_Mar09.htm Ausiàs.
  9. hello sir, here you have mentioned sir to divide the volcano scan corrected I/F spectra by a spectrum from the same corrected data for an area that looks like it is spectrally neutral area.? what is process of choosing spectrally neutral area in a corrected i/f image
  10. hello sir, i am PhD scholar currently working on classification of CRISM data . I have some doubt regarding mica type spectral library ,firstly what is the process of getting numerator I/F AND denominator I/F? secondly ,ratioed i/f corrected spectral profile graph range is different from the spectral profile of my matching image(i am using mtr3 dataset)?
  11. Earlier
  12. This is the 15th release of CRISM MTRDR and TER data products. In addition, the volume MROCR_2103 is updated with new TRDR browse and extras data products.
  13. Rochdi: Glad to have helped you along. Stay safe and healthy. Ray Arvidson
  14. Hello Sir Ray Arvidson, Sometimes I ask stupid questions, but I extracted the spectral signatures of those bright areas. Thanks a lot for your tremendous help Sir Ray, and thanks to Jennifer G. Ward for the mentioned paper. Rochdi.
  15. Rochdi: I am not sure what you are asking. CAT has spectral parameters for IR data. Use this function. I am not trying to be judgmental. However, I suggest that you need to read in detail the Viviano-Beck paper that was sent to you and that you become very familiar with CAT and its functions. Many of your queries would have been answered if you had done this homework in detail. Ray Arvidson
  16. That's it, Sir Hope I'm not bothering you, as you know the L (IR) cube is already converted into IOF. If I want to extract the spectral signature of these bright areas which highlighted in the output above, could I use CAT toolkit for this purpose? or just a tool from ENVI toolbox?
  17. Yes, although the Viviano-Beck paper that we sent to you shows which bands to use for her indices. If you use your own indices and select accordingly. Ray Arvidson
  18. Alright, then. Concerning other indices which have different reflectance values compared to L cube bands values. In this case, Can I assign the bands which are closest to the reflectance values of those indices? Rochdi.
  19. It should be a monochrome image with bright areas indicative of a high value for the spectral parameter used, yes. Ray Arvidson
  20. So, is the result I got above is the expected one?
  21. Result is one monochrome image. Do your band math in sensor space, use CAT to flatten the result, and then project. Results will have to be your task. I do not know where the pyroxene is located. Ray Arvidson
  22. Yes, after I read the documentation for how to represent algebraic expression on ENVI Band Math function. I realized that I need to modify the equation by adding float in the dominator as follows: HCPINDEX: ((float(b1) - float(b2)) / (float(b1) + float(b2))) * ((float(b1) - float(b3)) / (float(b1) + float(b3))) I come with this attached output result below. So, where's Pyroxene, then? or the result should be in three color compsites?
  23. Your band math seems to be missing parentheses at the appropriate places. Please read the band math documentation for how to represent algebraic expressions. Ray Arvidson
  24. Hello Sir Ray Arvidson, Thanks a lot, that's what I thought before. I used the ENVI tool you mentioned, I tried to write the formulation of HCPINDEX just to learn. HCPINDEX: (R1470 - R1050/R1470 + R1050) * (R1470 - R2067/R1470 + R2067) As I wrote the expression, I refered R1470, R1050 and R2067 to b1, b2 and b3 successively (X1.png). Then, a new window popped up to assign the variables (b1, b2 and b3) to their specific wavelengths. The following is the bands that I assigned to the variables (X2.png): b1 (R1470nm) => Band 73 (1473, 7nm) b2 (R1050nm)
  25. Yes, for each pixel in the scene R2210 means use the reflectance value at 2210 nm. ENVI's Band Math function will allow you to write an equation that when run produces the parameter map.The tool is in the ENVI5 series interfaces on the right hand side under Band Algebra. Also, the weightings a, b, etc. in the equations allow centering of the computation over the deepest part of the putative absorption feature, all relative to the wavelengths on the continuum on either side of the feature. Ray Arvidson
  26. Hi Jennifer, Thanks a lot for the attached paper, I found it useful for my Master thesis I'm working on. However, the mentioned indices above are still unclear to me for putting them into action. What I'm wondering about is these questions: Does R2210 mean reflectance at 2210nm? Do I need a value to assign it to R2210? if yes, could I use ENVI and CAT to get R2210 value, for example? I look forward to your reply, Rochdi.
  27. Rochdi, Please see the attached paper for an explanation of how the indices are calculated. Jennifer Viviano-Beck_et_al-2014-Journal_of_Geophysical_Research__Planets.pdf
  28. Hello Experts, I would like to learn how to calculate some indices to detect Gypsum and other minerals on Ritchey crater, I decided to start first with the formulations included in "CRISM Data Product Software Interface Specification" (as seen below) to seek out gypsum. However, I didn't clearly understand the syntax of the mentioned formulations, I mean (R, a, b ... etc), I found these formulations more detailed compared to the indices I've calculated before such as NDVI, EVI, SAVI ... (using Landsat8, Spot imageries). Would you please explain to me the syntax of these formulati
  29. November 13, 2020 – MRO HiRISE Updates - MRO HiRISE EDR, RDR, DTM and Anaglyph data products released through October 3, 2020 (Orbit 66499) See https://ode.rsl.wustl.edu/odeholdings/Mars_holdings.html
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