The frame rate of each of the sub-arrays might be different, depending on the scene. The image compressing processor chooses a different compression block size and other compression parameters for each sub-array:
US20130293752 application titled "Exposure Time Selection Using Stacked-Chip Image Sensors" by Honghong Peng and Brian Keelan proposes to use different exposure times for different sub-arrays, based on motion information determined by stacked processing circuitry:


