Definition of a Processing Unit
Each request is "worth" a proportional amount of processing unit(s) depending on what data and processing is requested. We define one processing unit (PU) as a request for:
- an output (image) size of 512 x 512 pixels,
- 3 collection input bands,
- one data
sampleper pixel (see sample),
- an output (image) format not exceeding 16 bits per pixel,
- without additional processing (e.g. orthorectification) applied,
- the request is processed on-the-fly (i.e.
processAPI, WMS, WMTS, WCS or FIS request).
In addition to this:
- The minimal weight for a request is 0.001 PU.
- The number of remaining processing units is reduced only when a request successfully executes, i.e. when the response code is
We use "multiplication factors" to calculate how many processing units are required for each request. The definition of 1 processing unit and the calculation rules are summarized in the table:
|Parameter/API||Quantity for 1 PU||Rules for multiplication factors|
|Output size (width x height)||512 x 512 px||The multiplication factor is calculated by dividing requested output (image) size (width x height) by 512 x 512.|
The minimum value of this multiplication factor is 0.01. This corresponds to an area of 0.25 km2 for Sentinel-2 data at 10 m spatial resolution.
|Number of input bands||3||The multiplication factor is calculated by dividing the requested number of input bands by 3.|
An exception is requesting
|Output format||8 bit or 16 bit|
|Requesting 32 bit float TIFF will result in a multiplication factor of 2 due to larger memory consumption and data traffic.|
Requesting application/octet-stream will result in a multiplication factor of 1.4 due to additional integration costs (This is used for integration with external tools such as xcube.).
|Number of data samples||1||The multiplication factor equals the number of data samples per pixel.|
|Orthorectification||No||Requesting orthorectification (for S1 GRD data) will result in a multiplication factor of 2 due to additional processing requirements (This rule is not applied at the moment.).|
|Batch Processing||No||Processing with |
Thus, three times more data can be processed comparing to
An example of the calculation of processing units for a Sentinel-1 change detection request (e.g. comparison of two time slices) is presented in the table below.
|Output size (width x height)||1024 x 1024 px||x 4||The requested output size is 1024 x 1024 px which is 4 times larger than the output size for one PU (512 x 512 px). Hence the multiplication factor is 4.|
|Number of input bands||4||x 4/3||4 input bands are requested, which is 4/3 times more than 3 input bands, which are included in one PU. The multiplication factor is thus 4/3.|
|Output format||32-bit float||x 2||The requested 32 bit float TIFF has a multiplication factor of 2.|
|Number of data samples||2||x 2||2 data samples (one for each time slice) were requested for each pixels. Thus the multiplication factor is 2.|
|Orthorectification||Yes||x 2||Ortorectification is requested, which results in a multiplication factor of 2.|
|Total||42.667 processing units||To calculate the number of processing units for this request multiply all the individual multiplication factors:|
4 x 4/3 x 2 x 2 x 2 = 42.667
Note: Statistical API (FIS requests) is also a multi-temporal request. The same rules for calculating multiplication factors apply.
An example of the calculation of processing units for the NDVI value over a 4 hectare large parcel at 10 m spatial resolution is presented in the table below.
|Output size (width x height)||20 x 20 px||x 0.01||The requested output size is 20 x 20 px which is smaller than the minimum area, thus the multiplication factor is 0.01.|
|Number of input bands||2||x 2/3||2 input bands are requested, thus the multiplication factor is 2/3.|
|Output format||16-bit tiff||x 1||The same as in the definition of one processing unit, thus the multiplication factor is 1.|
|Number of data samples||1||x 1||The same as in the definition of one processing unit, thus the multiplication factor is 1.|
|Orthorectification||No||x 1||The same as in the definition of one processing unit, thus the multiplication factor is 1.|
|Total||0.0067 processing units||To calculate the number of processing units for this request multiply all the individual multiplication factors: |
0.01 x 2/3 x 1 x 1 = 0.0067