Download indices

Compute band math for a specified area of interest (AOI) in the given scene using the Bandmath API.

HTTP Request

curl --location --request POST 'https://api-connect.eos.com/api/gdw/api?api_key=<your_api_key>' \
--header 'Content-Type: application/json' \
--data-raw '{
    "type": "bandmath",
    "params": {
            "view_id": "view_id",
            "bm_type": "bm_type",
            "geometry":{"type": "Polygon",
                   "coordinates": [[
                                         [lon,lat],
                                         [lon,lat],
                                         .........,
                                         [lon,lat]
                                      ]]
                       },
        "name_alias":"alias name",
        "reference": "ref_datetime"
    }
}'

Request Parameters

Parameter	Value	Description
api_key	<your api key>	(Required) Apikey retrieved from developer portal

Request Body Parameter	Description
type	(required) Operation name. Value is ‘bandmath’.
params	(required) Request parameters.
params.view_id	(required) View id of the scene returned by the Search API, see Search API. Example values: “L8/LC80110312016028LGN00”, “S2/19/T/CG/2017/7/9/0”, “MODIS/12/04/2017204/2017213034223” etc
params.geometry	(required to crop by AOI: either bbox, geometry or cropper_ref must be set) A GeoJSON representation of a geometry describing the AOI. Supported geometry types: “Polygon”, “MultiPolygon”. If neither geometry nor bbox were provided, then process a full scene
params.bm_type	(required) Band combination to calculate. Example: “(B5-B4)/(B5+B4),(B3-B5)/(B3+B5),(B3-B6)/(B3+B6)”, “B5-1” etc. For available band combinations please refer to Name Aliases and Supported Datasets
params.name_alias	(optional) User name of bandmath to be used in output file name.
params.reference	(required) Unique id to assign to the request

HTTP Response

The above commands returns the following JSON with task status

{
    "status": "status",
    "task_id": "task_id",
    "req_id": "req_id",
    "task_timeout": task_timeout
}

After that, you need to send a request for checking task status using task_id

Result image info:

• file name: <scene>_<combination>.TIF, where scene - lv_id or scene_id; combination - name_alias else bm_type
• number of bands equals the length of expressions list in bm_type, each band represents bandmath provided by its expression
• file format: GTiff
• depth: Float32
• tiled: yes, block=512x512
• pixel size and resolution: resample to the lowest resolution among bands in ‘args’.
• no data value == -9999

Limitation

Max supported area of AOI is 8 km2

For NAIP only R,G,B bands can participate in custom bandmath, since N band is not accessible

Examples: Download bandmath for an area of interest (AOI) for the given scene

Step 1: Create task for indices calculating with POST request

curl --location --request POST 'https://api-connect.eos.com/api/gdw/api' \
--header 'Content-Type: text/plain' \
--header 'x-api-key: <your_api_key>' \
--data '{
    "type": "bandmath",
    "params": {
            "view_id": "S2/13/R/EL/2023/7/19/0",
            "bm_type": "(B08-B04)/(B08+B04)",
            "geometry":{"type": "Polygon",
                    "coordinates": [
                        [
                            [-104.87931347024973, 27.166227117387663],
                            [-104.87190853064376,27.17371136921598],
                            [-104.87486446023671,27.175686643908065],
                            [-104.87271173924485,27.178599422270565],
                            [-104.87575466983847,27.180525385046096],
                            [-104.88103048496039,27.176643443128853],
                            [-104.87771956045358,27.172771682872458],
                            [-104.88236756436531,27.17042134807906],
                            [-104.87931347024973,27.166227117387663]
                            ]
                        ]
                       },
        "name_alias":"NDVI",
        "reference": "ref_datetime"
    }
}'

Example of response:

{
    "status": "created",
    "task_id": "a853944b-cb24-43e4-9d1c-c81e5429cdd4",
    "req_id": "6a45b628-d75b-4caf-aa33-9a3fdf6883fa",
    "task_timeout": 345600
}

Step 2: Receive the result of calculation with GET request and use task_id from previous step

curl --location --request GET 'https://api-connect.eos.com/api/gdw/api/a853944b-cb24-43e4-9d1c-c81e5429cdd4' \
--header 'x-api-key: <your_api_key>'

Example of response:

tip

You can download the image from response in .tiff format and open in any tool, such as QGIS