GEE Tutorial #43 - How to extract pixel values from an Earth Engine image using a point shapefile

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  • Опубліковано 2 лют 2025

КОМЕНТАРІ • 28

  • @Aswinkokkat
    @Aswinkokkat 2 роки тому

    Thankyou Prof. i followed this video and was able to extract the elevation valuve for 630 sites in Ganga basin

  • @mdtasimferdous9875
    @mdtasimferdous9875 8 місяців тому

    How can I extract the all band value data in csv format?

  • @mikeholad
    @mikeholad 2 роки тому

    Good day
    Please how do I create a city or state map on google earth engine using google colab (jupyter).

  • @thevgancheetah
    @thevgancheetah 2 роки тому

    I don't know why but the code below does not work after I import it through the interactive map.
    dataset fry = ee.ImageCollection('COPERNICUS/Landcover/100m/Proba-V-C3/Global'
    Map.addLayer(dataset_ffy, {}, "COPERNICUS/Landcover/100m/Proba-V-C3/Global")
    Nothing shows up on the map.

  • @afeworkalemayehu9434
    @afeworkalemayehu9434 Рік тому

    I appreciate dearest all the very important and useful videos you have been sharing. But how can I use a specific study area instead of a country?? To mean uploading shapefile or drawing/digitizing on GEE

  • @mohammadsadeghtahmouresi2709
    @mohammadsadeghtahmouresi2709 3 роки тому +1

    Hi thanks for this helpful video!
    I want to use a point shapefile (more than 50000 points) to extract TRMM (precipitation data)value as time series(for 20 years). can you do me a favor with this?

  • @leonardoippolito2687
    @leonardoippolito2687 2 роки тому

    Hi Sr. helpful package and video!! I was wondering how could i export the pixel value as a shp working in a colab env?

    • @giswqs
      @giswqs  2 роки тому

      It should work with both Colab and local Jupyter

  • @sav6639
    @sav6639 2 роки тому

    I would like to extract rasters of a composite image (which I generated using .median()) but I get the following error,
    "Image.reduceRegions: The default WGS84 projection is invalid for aggregations. Specify a scale or crs & crs_transform."
    I don't know what nominal value to put in the 'scale' parameter and how to go about it. Any help is appreciated (Thank you for the video)

  • @isabelahorta3063
    @isabelahorta3063 2 роки тому

    Thank you for the video! Do you know how can I download a CHIRPS time series for a point shapefile using GEE and python?

    • @giswqs
      @giswqs  2 роки тому +1

      Convert the image collection to image using collection.toBands(), then use geemap.extract_values_to_points() to extract values. See this example book.geemap.org/chapters/06_data_analysis.html#extracting-pixel-values

  • @patricknistahl374
    @patricknistahl374 3 роки тому +1

    Thank you very much for your helpful package and videos! I would like to use this function for large time series data sets (climate reanalysis) from GEE. Is it possible to make a loop over a large ImageCollection and storing all results in one file? Without changing the presented function I would have 1 csv-file per hour /6 hours for many decades.

    • @giswqs
      @giswqs  3 роки тому +2

      You just need to convert an ImageCollection to Image (e.g., image=collection.toBands()) and then follow the same procedure in the video to extract time-series pixel values.

    • @patricknistahl374
      @patricknistahl374 3 роки тому

      @@giswqs thank you, .toBands() is very helpful in this case. One more (and hopefully last) question: Like you described in the video, the columns are not in oder (time steps are randomly mixed) - can I avoid this somehow? Collection.sort seems to not work before since the time is not property of the ic.

    • @giswqs
      @giswqs  3 роки тому +1

      You can use .map to set image properties, e.g., image.set(‘property’, ‘value’)

    • @patricknistahl374
      @patricknistahl374 3 роки тому

      @@giswqs thanky you again! The function worked for me yesterday - without changing the script I get the following error today when calling the function extract_values_to_points: "ee.ee_exception.EEException: Image.reduceRegions: The default WGS84 projection is invalid for aggregations. Specify a scale or crs & crs_transform."

  • @ziyazhang-noaaaffiliate6859
    @ziyazhang-noaaaffiliate6859 3 роки тому

    I created an image collection and was able to extract data for some points. But the output (csv file) has a column called system:index which I really don't need. How can I avoid that column being included? Thankyou.

    • @giswqs
      @giswqs  3 роки тому

      That’s the one automatically generated by Earth Engine. I don’t think there is a way to avoid it. After the csv is downloaded, you can use pandas to remove the column if needed

  • @IAKhan-km4ph
    @IAKhan-km4ph 2 роки тому

    very nice

  • @lorenztratzmuller9835
    @lorenztratzmuller9835 3 роки тому

    Hi thanks again for this helpful video!
    I used this method for extracting pixel values out of a shapefile with around 60 objects. But for some reason when I export the values into excel it only export the valus from 10 points to excel. Does anybody knows how to fix this problem?

  • @hafezahmad3747
    @hafezahmad3747 4 роки тому

    thank you professor

  • @Ninguempensonesse
    @Ninguempensonesse 4 роки тому

    Can we extract the data of the 2 layers (Landsat and DEM), to the same file?

    • @giswqs
      @giswqs  4 роки тому +1

      You can merge the two images as one and then follow the same steps shown in the turorial, such as
      image = landsat.addBands(dem)

  • @abilitymatutu883
    @abilitymatutu883 11 місяців тому

    Share codes

  • @magnuspersson791
    @magnuspersson791 2 роки тому

    Hi, Great tutorial as always!
    I get the error: "Shapefile field limit exceeded: The maximum number of fields in a Shapefile is 255.", when i run geemap.extract_values_to_points. The FeatureCollection and the image is in the same crs. Do you have any tips on solving that?

    • @giswqs
      @giswqs  2 роки тому

      How many images in the ImageCollection. It should not be more than 255 images and if you are trying to export shp. Try CSV format

  • @adahal39
    @adahal39 4 роки тому

    Thank you so much for your effort for creating this awesome package. I need a script where I need to store more than 50 satellite images(band wise) directly into database(Postgis) I can obviously download it to local computer by using this package but I need to insert the images directly into database. Is there any way to accomplish this process. I am trying to do this process by using this library where I downloaded image collection into some temporary zip file and then I was planning to insert the images into database using psycopg2 and once the image is inserted I will delete the temporary file . Similarly for all other images inside a loop maybe. But still I am not able to do it. Is there any other way I can do this ?

    • @giswqs
      @giswqs  4 роки тому

      Sorry, I have not used PostGIS yet.