Weighted Ratio-Based Adaptive Lossless image coding

In this paper, we present an image compression algorithm called Weighted, Ratio-Based, Adaptive, Lossless image Codec (WRALIC). The algorithm utilizes 5 ratio predictions. The weight of each prediction is learned during a training stage offline, whereas the prediction parameters are adjusted using error context. The absolute value of the error is encoded. The algorithm does not encode the sign. Instead, it attempts to guess the sign of the error from the sign context of the pixel. Using the energy and the average errors around a pixel, the error is added to an encoding bin. Experimental results demonstrate good compression performance compared to other state of the art algorithms.