The display apparatus includes an image display element being driven based on a digital video signal, a quantizing part converting an input analog image signal into the digital video signal based on a quantization phase and a quantization frequency, and a converting part converting an input value into an output value, the input value being a difference value of signal values of pixels adjacent to each other in the digital video signal. The apparatus includes an accumulating part accumulating the output values from the converting part that converts the difference values obtained over entire pixels in one frame of the digital video signal to produce an accumulation evaluation value, and a controller adjusting the quantization phase in the quantizing part such that the accumulation evaluation value becomes maximum. The output values a(m) for the input values k1, k2 and k3 satisfy conditions of a(k1+1)−a(k1)