Understanding Mosaicking within EarthCache

The following article will cover what mosaicking is and how it is implemented within SkyWatch's EarthCache platform and how it affects the delivered imagery.

When attempting to capture an requested area it is possible for the area of interest to not be captured in one pass of the satellite, for such cases multiple scene captures are required in order to provide complete coverage, for such cases mosaicking can be used to return a single result for the pipeline.

The mosaicking process preserves the neighbouring pixels of each collection, each segment much satisfy the specified pipeline conditions (e.g., cloud coverage). The practical use for mosaicking is if the user doesn't require the entire AOI to be collected in a single day, otherwise single day mosaicking will need to be enabled; additionally mosaicking will provide flexibility so to ensure there is imagery for the entirety of your AOI. This is especially helpful for larger AOIs, such as for those that are 30km² or larger.

Details regarding the elements which makes up the mosaic can be be found in the accompanying metadata, this contains the used products and the date of their capture. It should be noted that image stitching does not provide a mosaicked result with full colour balancing and corrections to make it look like a single capture, there may be some colour differences between the parts of the stitched result.

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