中文摘要：

在医学图像的三维可视化中，不透明度传递函数和观察角度是需要频繁调节的，因此，难以实现实时体绘制。为了提高三维图像的视觉效果和重建效率，提出了一种加速的透视体绘制算法。依据不透明度传递函数的相关性对原有的min-max octree数据结构进行有效的再利用，从而加速体数据分类编码，以使在频繁改变不透明度传递函数和观察角度时，也能实现快速重建；基于透视Shear-Warp算法，并用即时中间切片插值重采样的方法，提高重建的效果。实验证明该方法不仅效率高，而且显示效果好。

英文摘要：

In the visualization of 3D medical images, it is common to adjust the opacity transfer function and viewing angle frequently so that volume rendering is difficult to be realized in real-time. In order to enhance the visualization effect and reconstruction efficiency of 3D medical images, a novel speedy perspective volume rendering method based on Shear-Warp method is proposed in this paper. Based on the correlation of the opacity transfer function, the original min-max octree data structure is re-used to carry out rapid classification encoding, thus rapid reconstruction can be realized even under the condition that the opacity transfer function and viewing angle are frequently changed. On the basis of Shear-Warp method, intermediate slice interpolation method is used to improve the effect of reconstruction. Experiments demonstrate the good performance of the proposed method.