1. A method for determining whether a third image pixel that is part of an image generated from a pixel array of an image sensor and comprising a plurality of image pixels, each having an image pixel value formed from a respective reset level generated in said pixel array, has suffered a darkening resulting from a drop in its reset level prior to sampling due to a high intensity illumination, the method comprising: finding, within said image sensor or within a processor coupled to said image sensor, a first image pixel among the plurality of image pixels whose reset level is detected to have crossed a threshold; finding a second image pixel among the plurality of image pixels that has a saturated image pixel value, the third image pixel being located between the first and second image pixels; and, determining that the third image pixel has suffered the darkening where its image pixel value is not saturated and where there is not an intervening image pixel among the plurality of image pixels that is located between the first and the third image pixels and that either has its image pixel value saturated or has its reset level detected to have crossed a threshold.