半叉迹特征的快速分形图像编码

传统的分形图像编码时间过长，限制了它的应用。为了加快编码速度，提出基于半叉迹特征的快速分形编码算法，该算法主要包括：定义子块半叉迹特征，导出子块的均方根误差与子块半叉迹特征之间的关系。实验结果表明：该算法较基本分析编码算法，在解码图像PSNR平均提高约0.63 dB的情况下，平均加快编码速度55倍；较文献[10]提出的主对角和算法和文献[11]提出的叉迹算法，在编码时间不变的情况下，改善了编码性能，提高了解码图像质量；基于子块特征的快速编码算法，其编码性能与图像的复杂程度有关，细节信息越丰富的图像，编码性能越差。

Semi-cross trace feature fast fractal image coding

Traditional fractal image coding is very time consuming, so its application is limited. To speed up the encoding speed, this paper proposes fast fractal coding algorithm based on semi-cross trace feature. The algorithm includes: defining semi-cross trace feature, achieving the relationship between the root mean square of sub-blocks error and the semi-cross trace feature of sub-blocks. Experimental results show that: when decoded image PSNR increases of about average 0.63 dB, the encoding speeds up average 55 times; the algorithm improves coding performance and improves the quality of decoded image in case of unchanged encoding time, compared with main diagonal sum feature from the literature[10] and cross trace feature from the literature[11]; the fast encoding algorithm based on sub-block feature, the coding performance is related to the complexity of image. The more abundance image details, the worse coding performance.