中文摘要：

Photon Mapping是一种在全局光照计算中得到广泛应用的算法，尤其在光线跟踪算法中Photon Mapping已成为计算全局光照的最重要的算法．针对Photon Mapping中光强估计过程计算速度较慢这一缺陷提出了一种较为高效的光强估计算法，该算法利用对场景中少量点的光强估计结果通过加权平均的方法来近似地计算出绘制点处的光强值．实验结果表明在典型场景中该方法的计算速度与原方法相比有3—5倍的提高，并且在图像质量方面也有令人满意的效果．

英文摘要：

The photon map method is an important method to efficiently compute global illumination in Ray Tracing. But the radiance estimate which used in Photon mapping to compute the radiance is time- consuming. A new method is presented which uses weighted average to accelerate the speed of radiance estimate. The tests indicate that the radiance estimate, which is the most time- consuming part, used in photon mapping can be sped up by 3 to 5 times in typical scene.