Liu Dong, Sun Xiaoyan, Wu Feng, Zhang Ya-Qin
University of Science and Technology of China, Hefei, China.
IEEE Trans Image Process. 2008 Oct;17(10):1827-36. doi: 10.1109/TIP.2008.2002835.
We propose an intra prediction solution to block-based image compression. In order to adapt to local image features during intra prediction, we consider the distinct image singularities within the model of piece-wise smooth functions. With such singularities, i.e., edges in this paper, intra prediction can be performed by solving Laplace equations. Moreover, since edges exhibit spatial correlations, we design a rate-distortion optimized method for edge extraction and edge coding. Our edge-oriented intra prediction thus consists of the prediction of smooth regions as well as the prediction of edges. We compare our intra prediction with that in H.264 and achieve superior performance. Our intra prediction can also be integrated into a block-based image coding scheme, which is comparable to JPEG2000 in terms of objective quality. An important advantage of our intra prediction is the improvement in visual quality at low bit-rate due to the preservation of edges.
我们提出了一种用于基于块的图像压缩的帧内预测解决方案。为了在帧内预测期间适应局部图像特征,我们在分段光滑函数模型中考虑不同的图像奇点。利用这些奇点,即本文中的边缘,通过求解拉普拉斯方程可以进行帧内预测。此外,由于边缘呈现空间相关性,我们设计了一种用于边缘提取和边缘编码的率失真优化方法。因此,我们面向边缘的帧内预测包括平滑区域的预测以及边缘的预测。我们将我们的帧内预测与H.264中的帧内预测进行比较,并取得了卓越的性能。我们的帧内预测还可以集成到基于块的图像编码方案中,该方案在客观质量方面与JPEG2000相当。我们帧内预测的一个重要优点是由于边缘的保留,在低比特率下视觉质量得到了改善。