In one example, an apparatus comprises: a first photodiode to generate a first charge; a second photodiode to generate a second charge; a quantizer; a first memory bank and a second memory bank; and a controller configured to: control the quantizer to perform a first quantization operation and a second quantization operation of the first charge to generate, respectively, a first digital output and a second digital output, the first and second quantization operations being associated with different intensity ranges; store one of the first digital output or the second digital output in the first memory bank; control the quantizer to perform a third quantization operation of the second charge to generate a third digital output, the third quantization operation being associated with a different intensity range from at least one of the first or second quantization operations; and store the third digital output in the second memory bank.