Patent ID: 8417044

Claim:
An image encoding method comprising: generating a second image including n-bit difference values by respectively subtracting predicted values of n-bit pixel values in a first image from the n-bit pixel values in the first image, where n is a positive integer equal to or greater than 1; determining an offset for adjusting a distribution of the n-bit difference values in the second image, based on the distribution of the n-bit difference values in the second image; generating a third image by adding the offset to the n-bit difference values in the second image, where the third image comprises an adjusted distribution of the n-bit difference values; dividing the third image into a first image plane corresponding to m lower bits and a second image plane corresponding to (n−m) upper bits, where m is a number of bits determined based on the offset and m is a positive integer less than or equal to n; and respectively entropy-encoding the first and the second image planes according to different entropy encoding methods.