Patent ID: 6909433

Claim:
An image display apparatus comprising: first storage means for storing image data in compressed form; first designation means for designating partial image data to be screen-displayed from the image data; second storage means for storing the partial image data designated by said first designation means and peripheral data of the partial image data in compressed form; expansion means for expanding the partial image data and the peripheral data stored in compressed form in said second storage means; third storage means for storing the partial image data and the peripheral data expanded by said expansion means; screen-display means for screen-displaying the partial image data stored in said third storage means; second designation means for designating the partial image data to be screen-displayed next; prediction means for predicting a necessity of required image data, being peripheral data of the partial image data designated by said second designation means, and not stored in said second storage means; and transfer means for, in accordance with the result of the prediction by said prediction means, reading the required image data from the image data stored in said first storage means and transferring the image data to said second storage means.