What is Gaussian Blur in image processing?

What is Gaussian Blur in image processing?

In image processing, a Gaussian blur (also known as Gaussian smoothing) is the result of blurring an image by a Gaussian function (named after mathematician and scientist Carl Friedrich Gauss). It is a widely used effect in graphics software, typically to reduce image noise and reduce detail.

What is kernel size in Gaussian Blur?

Applies a gaussian blur filter. Applies median value to central pixel within a kernel size (ksize x ksize). The function is a wrapper for the OpenCV function gaussian blur.

What is kernel in Gaussian Blur?

In a blur, we consider a rectangular group of pixels surrounding the pixel to filter. This group of pixels, called the kernel, moves along with the pixel that is being filtered. So that the filter pixel is always in the center of the kernel, the width and height of the kernel must be odd.

How is the Gaussian blur used in photography?

The Gaussian blur feature is obtained by blurring (smoothing) an image using a Gaussian function to reduce the noise level, as shown in Fig. 10.3 H. It can be considered as a nonuniform low-pass filter that preserves low spatial frequency and reduces image noise and negligible details in an image.

How to choose an optimal discrete approximation of the Gaussian blur?

The parameter sigma is enough to define the Gaussian blur from a continuous point of view. In practice however, images and convolution kernels are discrete. How to choose an optimal discrete approximation of the continuous Gaussian kernel?

How to approximate a 3 × 3 Gaussian kernel?

From wiki, a 3 × 3 gaussian kernel is approximated as: 1 16[1 2 1 2 4 2 1 2 1]. Applying this kernel in an image equals to applying an one-dimensional kernel in x-direction then again in y-direction, so one-dimensional kernel is 1 4[1 2 1]. for 3*3 kernel 1 16[1 4 6 4 1]. for 5*5 kernel My question is how to derive this approximation?

How is the Gaussian blur used in machine learning?

Siddharth Misra, Yaokun Wu, in Machine Learning for Subsurface Characterization, 2020 The Gaussian blur feature is obtained by blurring (smoothing) an image using a Gaussian function to reduce the noise level, as shown in Fig. 10.3 H.