A coding device is comprised of an initial resolution coding unit for coding an initial resolution image sub-sampled from an image at every interval of predetermined pixels, and a high resolution coding unit for coding images at sub-sampling intervals sequentially halved, wherein said high resolution coding unit comprises a pixel value predicting means for, out of the pixels that should be coded in present resolution, predicting a value of a pixel being positioned at a center of its adjacent four pixels already coded in previous resolution from said adjacent four pixels with a linear interpolation, and predicting a value of a remaining pixel from its adjacent four pixels having the above pixel at a center thereof with the linear interpolation, said adjacent four pixels being positioned in an upper, lower, left and right sides of the above pixel, a prediction error calculating means for obtaining a residual between the pixel value of the to-be-coded pixel and the predicted value, and a variable length coding means for coding the residual.