Efficient memory data organization for fast still image decoding implementation

This paper proposes a new still image codec. The encoder has the following structure: a set of pixels of the image is selected and transmitted, together with their position. Then, the value of the image at other places is obtained by a prediction algorithm at the decoder. A useful theoretical covariance model adapted to the image to be encoded is proposed, avoiding the transmission of additional information. The selected pixels and their corresponding positions on the image are encoded using lossless coding algorithms. The computational time of the decoding process is significantly reduced according to the efficient structured memory organization of (i) the image covariance values and (ii) the ordered distances concerning the search of nearest pixels. Experimental results performed on a set of test images show that the rate- distortion results are competitive to the best coders JPEG 2000 and SPIHT with arithmetic coding.