An image capture method in a digital image sensor implements a continuous
sampling technique with a massively parallel thermometer-code
analog-to-digital conversion (ADC) technique to generate pixel data
having an intrinsic to an ultra-high dynamic range. In one embodiment,
the method includes, after an initial exposure period, sampling pixel
intensity values at the pixel elements of an image sensor at multiple
exposure times within a snapshot of a scene; providing an analog
reference voltage corresponding to a decrementing digital count value;
and comparing the pixel intensity values to the analog reference voltage
at each of the multiple exposure times. If the pixel intensity value of a
first pixel element is less than the analog reference voltage at a first
exposure time, an output signal having a first value is generated and the
digital count value is recorded as pixel data associated with the first
pixel element.