Why Gaussian Blur Is Used?

Gaussian blurring is commonly used when reducing the size of an image. When downsampling an image, it is common to apply a low-pass filter to the image prior to resampling. This is to ensure that spurious high-frequency information does not appear in the downsampled image (aliasing).

What is the use of Gaussian Blur in Photoshop?

There are many reasons to use the Gaussian Blur filter in Photoshop. You can use it to reduce noise, add an artistic blur effect, or create depth by blurring the background. The Gaussian effect results in a smooth blur that looks as if you are viewing the photograph through a translucent screen.

What does a Gaussian filter do to an image?

The effect of Gaussian smoothing is to blur an image, in a similar fashion to the mean filter. The degree of smoothing is determined by the standard deviation of the Gaussian. (Larger standard deviation Gaussians, of course, require larger convolution kernels in order to be accurately represented.)