JPEG Codec

Experiments with a Lossless JPEG Codec

The ISO JPEG Still Image Compression Standard is popularly known for its DCT-based compression technique, but its non-DCT based lossless mode of operation is less well known. Lossless JPEG uses a form of discrete pulse code modulation (DPCM) [3]. That is, a linear combination of a pixel’s left, upper and upper left neighbors is used to predict the pixel’s value, and the difference between the p...

Experiments with a Lossless Jpeg Codec

JASPER: A Software-Based JPEG-2000 Codec Implementation

A software-based implementation of the image codec specified in the emerging JPEG-2000 standard is discussed. The run-time complexity and coding performance of this implementation are also briefly analyzed.

Highly Scalable Differential JPEG-2000 Wavelet Video Codec for Internet Video Streaming

Highly scalable wavelet video codec is proposed for Internet video streaming applications based on the simplified JPEG-2000 compression core. Most of existing video solutions are utilizing fixed temporal grouping structure, resulting in quality degradation due to structural mismatch with inherent motion and scene change. Thus, by adopting the adaptive frame grouping based on the fast scene chan...

Comparative investigation of a non-linear predictive codec versus JPEG lossless compression

A non-linear predictive coding based algorithm is proposed in the paper for lossless image compression. The algorithm uses two neighbouring pixels, one left and the other top, as a pioneering block to search for the best matched blocks inside a pre-defined window. The corresponding pixels associated with the best matched blocks are then taken to produce the predictive value, together with the t...