基于梯度矢量方向性分析的线裁剪算法

在传统线裁剪(seam carving)算法中梯度矢量的方向性是一个被忽略的因素，该文提出了一种新的基于梯度矢量方向性分析的线裁剪算法。首先利用随机纹理区域内梯度矢量方向散乱的特点，对局部区域的图像梯度矢量进行低通滤波，使算法能够提取更加合理的像素线路；接着又根据像素线路的走向不同，定义两个不同的像素能量函数，给予像素梯度矢量的x, y分量以不同的权值。实验结果图像显示，文中算法不仅可以更好地保护图像边缘等细节，还可以在整体上达到与原图像更加近似的视觉效果。定量分析结果也显示，相比其它算法该文算法在完整性距离和一致性距离两方面都取得了更好结果。

Seam Carving Algorithm Based on Gradient Vector Direction Analysis

The direction of gradient vector is a factor being omitted in traditional seam carving.A new seam carving algorithm is proposed in this paper based on gradient vector direction analysis.A low-pass filter is firstly used on the local gradient vector to extract more suitable seams based on the fact that the gradient vector directions in random texture regions are usually disordered.Then two different pixel energy functions are defined,which give different weights to the x,y direction components of pixels gradient vectors based on different path direction of seams.The experiment results show that the method can better protect the image edge and other details and can reach more similar overall visual effect with original images.Quantitative analysis results also show that the algorithm achieves better results in both image completeness distance and image coherence distance than other methods.