A new quadtree predictive image coder
A new quadtree-based lossy image compression algorithm is introduced. One new feature is that one pixel in each quadtree block is predictively encoded while the remaining pixels are linearly predicted from this one and from pixels of previous blocks. Another is that the criteria for subdividing a block involves the reproduction error in each pixel, as opposed to the error energy for the entire block. Though the algorithm has very low complexity, its predictive nature gives it good rate/distortion performance and suppresses blocking artifacts. This paper describes the algorithm, shows the results of coding at .5 and .25 bits per pixel, and compares its peak signal-to-noise ratio with other methods.