DCT-based scheme for lossless image compression
Giridhar D. Mandyam, Nasir Udin Ahmed, Neeraj Magotra · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1995
In this paper, a new method to achieve lossless compression of 2D images based on the discrete cosine transform (DCT) is proposed. This method quantizes the high energy DCT coefficients in each block, finds an inverse DCT from only these quantized coefficients, and forms an error residual sequence to be coded. Furthermore, a simple delta modulation scheme is performed on the coefficients that exploits correlation between high energy DCT coefficients in neighboring blocks of an image. The resulting sequence is compressed by using an entropy coder, and simulations show the results to be promising and more effective than just simply performing entropy coding on original raw image data.