Note: The Level-1A product is not released to users
The Level-1A product is obtained by decompressing image data and developing a geometric model to locate any pixel in the image.
Figure 1: Level-1A Processing Overview
Level-1A processing includes:
Level-1 viewing model initialisation
Level-1A radiometric processing
Level-1 Viewing Model Initialisation
This processing step computes the viewing model that will be used to initialize Level-1B processing. It uses the Precise Orbit Determination (POD) products generated by the Mission Performance Centre Coordinating Centre (MPC/CC).
This processing step decompresses the ISPs.
Level-1A Radiometric Processing
This step includes the SWIR pixels arrangement.
This processing step uses the JPEG2000 algorithm to compress the Level-1A imagery.