小波图像降噪及图像测试技术的研究.doc

小波图像降噪及图像测试技术的研究 摘 要 图像在生成和传输的过程中会受到各种噪声的影响而产生干扰，对人们获取，传输和存储信息造成负面影响。所以我们需要去除图像中的噪声。随着小波理论的不断完善，小波在图像降噪中得到了广泛的应用。小波降噪有很强的理论意义和应用价值。 傅立叶变换能有效地稀疏表示图像中有一定变化周期规律的纹理部分和变化平缓的部分，但是不能有效的表示图像中的突变部分，小波变换能稀疏表示包含尖锐变化部分的信号如图像中的边，但缺点是不能有效表示图像中的纹理和缓慢变化的部分。本文通过对傅里叶图像降噪和小波图像降噪进行量化和对比研究，综合傅里叶降噪和小波降噪的不同特性，提出傅里叶—小波混合降噪的方法，比傅里叶降噪和小波降噪效果要好，在图像降噪方向有更好的应用前景。 图像传输是现代通信的重要内容之一。图像压缩可以减少传输数据量，提高通信速度。因此，图像压缩技术有很高的研究和应用价值。本文通过对图像做量化和编码处理，达到压缩的目的。进行量化的方式主要是采用阈值设置，对采用不同小波变换后得到的低频和高频图像设置不同的阈值，得到的分解图像的含有0数目及重构产生的不同图像文件大小作分析，这是本次阈值测试的主要目的。 关键词：噪声 傅里叶—小波混合降噪 图像压缩 阈值测试 Research On Wavelet Image Denoising and Image Test Abstract Image will be subjected by the influence of various noise and interference in the process of generation and transmission, it will take a negative impact when people transport and storage information. So we need to remove the noise in the image. With the continuous improvement of wavelet theory, wavelet has been widely used in image denoising. Wavelet denoising has a strong theoretical and practical value.Fourier transform can effectively express the grain of certain changes and the smooth transformation part in the image, but can not effectively express the mutations in the image part, the wavelet transform can effectively express the sharp part of the image ，for example the Edge of the image. but can not effectively express the grain of certain changes and the smooth transformation part in the image. By quantitative and comparative study of the Fourier image denoising and wavelet image denoising, and synthesize the difference characteristics of the Fourier Transform and Wavelet Transform in this paper. Hybrid Fourier - Wavelet image denoising will be put forward. Hybrid Fourier - Wavelet image denoising has a better effect on denoising than the Fourier denoising and wavelet denoising,and it has better prospects for application on image denoising direction. Image transmission is an important part of modern communication. Image compression can reduce the transmission o