Method and apparatus are provided for determining and adjusting drive values for a display comprising a light source modulation layer such as a backlight array of LED and a display modulation layer such as an LCD panel. Image regions for which any of the display modulation layer drive values are above a predetermined threshold maximum value or below a predetermined threshold minimum value are flagged. The light source modulation layer control values determined for a subsequent frame of image data may be adjusted based on the flagged image regions. The adjustments to the light source modulation layer control values may reduce artifacts in the displayed image and increase the efficiency of the display.