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Image products

Product levels​

Satellite image data received from a ground segment undergoes multiple processing stages to produce usable image data products. Each stage provides products with varying amounts of data manipulation and advancement toward a usable image.

The processing level and output data formats can be tailored to operational requirements. FarEarth uses the following definition for our product levels, read more in our product levels info sheet.

Image product levels

STAC compliant​

Image formats​

File naming conventions​

Product metadata​

Product quality reports​

Typical product quality​

Product quality depends on the quality of the input data.

Geometric accuracy​

  • Absolute geolocation: sub-pixel
    • Typically, offsets are less than 1 pixel (CE95) from the reference image
    • When using Sentinel-2 as a reference, this means an accuracy in the range of 10 meters
  • Band-to-band alignment: less than 0.3 pixels (CE95)
    • With bands of different resolutions, this would mean sub-pixel co-registration of the lowest resolution band

Radiometric accuracy​

  • Absolute top-of-atmosphere (TOA) error in radiance: 5-10%
  • Inter-band relative radiometric uncertainty: better than 5% consistency across bands
  • Multi-temporal relative radiometric uncertainty: better than 2% over time for any given spectral channel

To maintain an optimal geometric model, we automatically split long acquisitions into roughly square scenes

How to achieve maximum product quality​

We use several external references during processing, such as Sentinel-2, Landsat, or client-provided. The best product quality is achieved if the input data is of good quality. Below is a guideline of the input needed to produce excellent products. We understand input data is not always ideal. Do not worry, FarEarth can still produce products.

  • Your input data should preferably be free of haze with less than 10% cloud cover
  • Scenes over polar regions or oceans will have less accurate geolocation because of a lack of reference data
  • Scenes with visible features such as roads and rivers have better geolocation accuracy
  • Large water bodies can impact the accuracy

How to achieve maximum product quality Level 2A bottom-of-atmosphere products​

  • Reflective bands: images must include blue, green, red, NIR and preferably SWIR bands
  • Emissive bands: images must include red and NIR bands, and preferably two emissive bands

Product thumbnails​

  • Related links #1
  • Related links #2