The invention relates to a method and a pulse processing circuit (100) for the processing of current pulses (CP) generated by incident photons (X) in a piece of converter material, for instance in a pixel (11) of a radiation detector. Deviations of the pulse shape from a reference are detected and used to identify pulse corruption due to pile-up effects at high count rates and/or charge sharing between neighboring pixels. The deviation detection may for instance be achieved by generating, with a pulse shaper (110), bipolar shaped pulses from the current pulse (CP) and/or two shaped pulses of different shapes which can be compared to each other.