1. An organic light emitting diode (OLED) display driver circuit comprising: gamma circuitry; a first input to receive a luminance scaling factor per pixel from a scaling source, the luminance scaling factor per pixel separate from gamma values and gamma correction, the luminance scaling factor per pixel having a value within a range of values for the luminance scaling factor per pixel, the scaling source being independent from the gamma circuitry; a second input to receive an image input signal, the image input signal including a digital representation of a desired output for pixels within an OLED display; and a luminance scaling circuit to receive a pixel-level analog output voltage for each pixel and multiply the pixel-level analog output voltage for each pixel, corresponding to the image input signal, by the respective luminance scaling factor of each pixel, the luminance scaling circuit operable to change luminance across the OLED display, independent of gamma adjustment by use of the luminance scaling factor independent of the image input signal.