In digital display circuitry, configured to display an image encoded in an analog display signal, the digital display circuitry includes analog-to-digital converter (ADC) circuitry to recover pixel data elements of the image. During vertical blanking intervals of the analog display signal, the ADC circuitry is calibrated. Outside the vertical blanking intervals, the ADC circuitry is used to convert information in the analog display signal into digital representations of the pixel data elements. For example, the calibrating may include determining more acceptable values for certain ones of the operational parameters of the ADC circuitry.