Compression device and compression method

An method for operating a compression device, which includes a memory having a first area to store a first totalizing value of a first pixel of a pixel group, a second area to store first selection information corresponding to a model selected to calculate a first prediction value for second totalizing values of peripheral pixels of the pixel group other than the first pixel, and a third area to store first differences between the second totalizing values and the first predication value, the method comprising:

• obtaining the second totalizing values based on information stored in the first through, second, and third areas;
• obtaining a third totalizing value by adding a first current luminance value of the first pixel to the first totalizing value;
• obtaining fourth totalizing values by adding second current luminance values of the peripheral pixels to the second totalizing values;
• and
• storing the third totalizing value and the fourth totalizing values.

A compression device, comprising:

• a predictor to calculate prediction values of peripheral pixels based on totalizing information of a first pixel;
• a calculator to calculate totalizing values of the peripheral pixels based on the prediction values, and to add a luminance value to a totalizing value of the first pixel and the totalizing values of the peripheral pixels to generate updated totalizing values;
• a model selector to select a model from a plurality of models;
• a subtractor to determine differences between information of the model and the updated totalizing values;
• quantizing the updated totalizing values;
• and
• controlling storage of the quantized updated totalizing values and the differences determined by the subtractor in a memory, the quantized updated totalizing values corresponding to compressed pixel values.