Method and apparatus for driving liquid crystal display device

The driving apparatus for a liquid crystal display device, comprising:

• an image signal modulator receiving first data for a current frame, retrieving brightness histograms for at least two frames prior to the current frame to generate an average histogram, and generating second data for the current frame based on the average histogram;
• a back light controller generating a brightness control signal based on the average histogram;
• an image discriminator comparing the histogram for the current frame with the average histogram to determine whether an image at the current frame is a moving image or a still image;
• a selector receiving the first data and the second data and selectively outputting one of the first data and the second data based on the discrimination result;
• and
• an image area selector extracting a portion of the brightness components for the first data for a current frame to be inputted to the image signal modulator,
• wherein the image signal modulator stores the histograms for at least two frames that are immediately prior to the current frame, assigns weighting values to the stored histograms;
• and converting the histograms assigned with the weighting values into average values to produce the average histogram.