一种改进的自然纹理合成方法

自然纹理合成方法是一种适合自然景物的基于样图的快速纹理合成方法。 但是候选点超越样图边界的问题没有很好得到解决，成为导致合成后图像产生的纹理块间明 显变化的主要因素。论文提出了一种改进的自然纹理合成算法，将样图边缘易产生无效候选 点的区域用样图内部与之大小和形状相同的像素块来代替，像素块和被替代像素块沿一条不 规则的曲线相匹配。合成过程中在接近边缘时像素块的生长会转向纹理内部。该方法减少了 因随机产生候选点而形成的块间不连续，有效地改善了视觉效果。

An improved method of natural texture synthesis

Algorithm of natural texture synthesis is an efficient and excellent synthesis method based on sample images, especially applicable to natural plant. However, the problem of candidate pixels going out of sample image borders is not solved ideally, which mainly causes the obvious seams between two pixel blocks. This paper presents a modified algorithm of natural texture synthesis. The pixels that cause invalid candidate points are all at the border of the sample image, the pixel regions at the border of sample are replaced by the other pixel blocks within the sample in our algorithm. The replacing one is of the same shape and size as the target one. Also the pixel colors of a replaced region and the target one are well matched along an irregular line. In synthesis process, the growth of a pixel block can turn to a replacing pixel block when touching the boundary of the sample image, and thus the seams among texture blocks are obviously reduced, and the output image quality is highly improved.