Difference Eigenvalue Based Gaussian Noise Variance Estimation for Images
نویسندگان
چکیده
Noise tends to impact the accuracy of digital image processing significantly. In this paper, a difference eigenvalue based noise variance estimation method is presented. This method first calculates the difference eigenvalue edge indicator values of every pixel in an image. Then, according to the indicator values, a proper threshold is set to determine if a pixel is a homogeneous or texture one. Next, the image is separated into many blocks and the blocks including only homogeneous pixels are selected for the next averaging step. Last, pixel value variances of the selected homogeneous blocks are averaged leading to the global estimation result. Key-Words: difference eigenvalue, noise estimation, digital image processing, blocks, texture, variance
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