关键词: 图像平滑, 高斯滤波器, 空间距离, 像素距离, 自适应权值

Abstract: As the image enhancement techniques for image denoising，the traditional image smoothing methods can improve the signal-to-noise ratio（SNR） of image，but at the meantime also blur the image.For overcoming these disadvantages，an improved adaptive Gaussian filter is introduced.The filter，which combines the properties of Gaussian filter and Gradient Inverse Weighting Filter，takes simultaneously the space distance and pixel distance into account，so as to choose the pixels and their weights for local smoothing.The filter maintains the local image characteristic，expecially on the edges and details，while it depresses the computational performance.The experiments compare the performance of the filter with other filters，and the results demonstrate the validity of the filter.

Key words: image smoothing, Gaussian filter, space distance, pixel distance, adaptive weight