nemozone

Using GIMP to blur information is a simple process. To begin, open the image you want to blur in GIMP and select the Blur/Sharpen tool from the Tools menu. You can also call the tool by clicking the tool icon in the Toolbox or by using the keyboard shortcut Shift+U. Once the tool is selected, you can adjust the settings for the type of blur that you are applying. The normal Blur effect only softens the selection, but can be applied multiple times for a stronger effect; the Gaussian blur enables you to adjust the horizontal and vertical blur radius for a very blurry effect; the Motion blur enables you to adjust the blur length and angle to create the impression of movement; and the Pixelize blur enables you to adjust the pixel width and height of the selection to create a pixelated blur distortion.

Once you have adjusted the settings, click and drag your mouse cursor over the part of the image you want to blur. You can apply different blur effects to different things in your image, such as applying a Pixelize blur to a face and a Gaussian blur to an offensive slogan. After you are satisfied with the preview, click “OK” to apply the blur effect to the selection in the image. If you need to make more things blurry, use one of the selection tools to select another area of the image and repeat the process.

For a more intense blur effect, you can also use the Gaussian Blur Overlays technique. To do this, create a duplicate layer in the image, lighten it and blur it, and combine it using a layer mode with the original. Select the Blur Overlay layer in the Layers dialog and select “Overlay” in the “Mode” drop-down box. Then go back to the image window and apply a Levels or Curves and adjust it until the overall image has the proper brightness. Finally, go back to the image window and select Filters –> Blur –> Gaussian Blur and adjust the value until you get the desired effect.

Well, if you have very sensitive information, don't use blur. Just saying.

Citations :

1. https://www.gimp.org/tutorials/Blur_Overlays/
2. https://smallbusiness.chron.com/make-things-blurry-using-gimp-77113.html#:~:text=Click%20%22Filters%22%20from%20the%20menu,from%20the%20list%20of%20options.
3. https://www.adobe.com/lu_en/creativecloud/photography/discover/blur-image.html
4. https://docs.gimp.org/2.10/en/gimp-tool-convolve.html#:~:text=From%20the%20image%2Dmenu%3A%20Tools,the%20keyboard%20shortcut%20Shift%2BU.
5. https://www.educba.com/blur-effect-in-gimp/
6. https://www.youtube.com/watch?v=K9jl0Vgsyvo
7. https://thegimptutorials.com/how-to-blur-background/
8. https://smallbusiness.chron.com/make-things-blurry-using-gimp-77113.html
9. https://docs.gimp.org/2.10/en/gimp-tool-convolve.html